Section 74 of the Highways Act 1980 allows a highway authority to prescribe a frontage line for building, known as a building line, for one or both sides of a highway it maintains, and provides that no new building other than a boundary wall or fence may be erected nearer the centre line of the highway than that building line without the authority’s consent.

What a building line actually is

A building line under section 74 is a line set by the highway authority responsible for a particular road, marking how close to that road new building work is generally allowed to come. It applies to a highway maintainable at the public expense, and the authority can set it for one side of the road, or both, depending on the specific stretch involved. Not every road has a building line prescribed; where none exists, section 74 has nothing to add to the ordinary planning and building control requirements that apply anyway.

The consent requirement

Where a building line has been set, section 74 says no new building, other than a boundary wall or fence, and no permanent excavation below the level of the highway, may be erected or made nearer the centre line of the highway than the building line, except with the authority’s consent. A conservatory extending the frontage of a house toward the road is a new building for this purpose, so if it would sit nearer the road than a prescribed building line, this consent requirement applies on top of, not instead of, planning permission and Building Regulations.

How consent decisions are made

The highway authority can give consent for a specified period and attach conditions it considers appropriate, and any conditions attached bind successors in title, lessees and occupiers of the land affected, not just the person who originally obtained consent. Section 74 also confirms that consent cannot be unreasonably withheld, and that any dispute about whether withholding consent was unreasonable can be determined by the responsible minister, except on highways where the minister is itself the highway authority.

What happens without consent

Building nearer the highway than a prescribed building line without the required consent is an offence under the Act, carrying a fine, with a continuing daily penalty for an ongoing contravention. Where a building line prescription itself causes loss to a property owner, for example by restricting how their land can be used, there is a route to claim compensation, but this has to be pursued within six months of the line being prescribed or of notice of it being given, a considerably shorter window than many other property-related time limits.

How this differs from planning permission

A building line consent is a distinct requirement from planning permission and from Building Regulations approval, administered by the highway authority rather than the local planning authority or building control body, even though in many areas the same council may hold more than one of these functions. Getting planning permission for a conservatory does not itself confirm compliance with a building line restriction if one applies to the property’s road, and the two should be checked separately rather than assumed to be covered by a single approval.

Checking whether a building line applies

Because building lines are not universal and are specific to particular roads where a highway authority has chosen to set one, checking with the relevant highway authority, generally the local council in its highway authority capacity, before finalising the position of a conservatory close to the road frontage is the way to confirm whether this additional consent requirement applies to a specific property, rather than assuming it either does or does not without checking.

FAQs

Does every road have a section 74 building line?

No. A building line only applies where the relevant highway authority has specifically prescribed one for that stretch of road.

Does planning permission for a conservatory also cover a building line consent?

No. These are separate requirements administered under different powers, and both need to be checked where a building line applies.

Can a highway authority refuse consent for any reason?

Section 74 says consent cannot be unreasonably withheld, and a dispute about this can be referred to the responsible minister.

What happens if a conservatory is built nearer the road than a building line without consent?

It is an offence under the Act, carrying a fine, with a further daily penalty for a continuing contravention.

Bottom line

Where a highway authority has prescribed a section 74 building line under the Highways Act 1980, a conservatory built nearer the road than that line needs the authority’s specific consent, separate from planning permission and Building Regulations approval, and building without it is a criminal offence. Consent cannot be unreasonably withheld, and compensation for loss caused by a building line prescription has to be claimed within six months. This is general information, not legal advice on a specific property; the relevant highway authority can confirm whether a building line applies before design work is finalised.

Sources

This guide draws on the following primary sources, current as of 22 September 2026:

• legislation.gov.uk, “Highways Act 1980, section 74: Building lines”

Related guides

Compare Conservatories is an independent guide. We may earn a fee from some links; this never affects what we write. This article is general information, not legal or planning advice on any specific property — always confirm requirements directly with your local planning authority.

GOV.UK’s guidance on Approved Document O states that it applies to new residential buildings, and does not extend that scope to extensions or conservatories added to an existing dwelling, meaning the overheating limits and assessment methods in Part O are not the regulatory route that governs a conservatory’s design against overheating.

What Part O actually is

Part O of Schedule 1 to the Building Regulations sets requirements aimed at limiting unwanted solar gain and providing ways to remove excess heat from residential spaces, addressing the risk that increasingly airtight, well-insulated new homes can overheat in summer. Approved Document O, the guidance supporting these requirements, took effect from 15 June 2022, giving designers a route to demonstrate compliance through either a simplified method or dynamic thermal modelling.

Who it applies to

GOV.UK’s own description of the scope is direct: Approved Document O applies to new residential buildings. This is a narrower scope than the Building Regulations as a whole, which cover many kinds of work to existing buildings as well as new ones, and it means Part O’s specific overheating assessment requirements are targeted at new dwellings being designed and built from scratch.

Why a conservatory is different

A conservatory added to an existing home is an extension, not a new residential building in its own right, and GOV.UK’s guidance does not extend Part O’s scope to this kind of work. This means the specific overheating limits, assessment methods and compliance routes set out in Approved Document O are not the regulatory mechanism that applies when a conservatory is designed, even though a conservatory is, in ordinary terms, exactly the kind of heavily glazed space most likely to overheat.

What still governs heat performance

This does not mean a conservatory’s thermal performance is unregulated. Where a conservatory falls outside the Schedule 2 exemption covered elsewhere on this site, and the full Building Regulations apply, requirements for thermal separation, glazing performance and energy efficiency covered under other parts of the Regulations still apply to the extension. Where the conservatory is within the exemption, its thermal performance is instead a matter of design choice and product specification, covered in more practical terms elsewhere on this site, such as glazing U-values and shading, rather than a Part O compliance exercise.

Why the confusion happens

Part O was introduced specifically because of concern about overheating risk in modern housing, and a conservatory is a very visible, everyday example of a space prone to overheating, which is likely why homeowners and even some installers assume the new regulation must apply to it. The scope GOV.UK sets out, new residential buildings only, is narrower than that assumption, and confirming this distinction avoids treating a Part O compliance exercise, designed for new-build design teams, as something a conservatory project needs to go through.

What this means in practice

For a homeowner adding a conservatory, the practical route to avoiding an overheated space remains the design and product choices covered elsewhere on this site: glazing specification, shading, ventilation and orientation, rather than a Part O assessment. For a homeowner buying a genuinely new-build home that includes a conservatory or similarly glazed space as part of the original design, Part O will have applied to the whole new dwelling at the design stage, including that space, because the building as a whole was new construction rather than an extension to an existing home.

Why installers shouldn’t cite Part O as a requirement

Because Part O is relatively recent and specifically framed around a genuine overheating problem in new housing, a homeowner may come across it mentioned in connection with a conservatory quote or specification. Given GOV.UK’s stated scope, an installer citing Part O compliance as something legally required for an extension to an existing home is describing a stricter position than the regulation itself sets out; that does not mean good glazing and shading specification are unimportant, only that they are a design and performance choice for a conservatory, not a Part O legal compliance exercise in the way they would be for a new dwelling.

FAQs

Does Approved Document O apply to a conservatory added to an existing home?

No. GOV.UK’s guidance says Approved Document O applies to new residential buildings, not to extensions such as a conservatory.

When did Approved Document O come into force?

15 June 2022, for new residential buildings in England.

Is a conservatory’s overheating risk unregulated because Part O doesn’t apply?

Not entirely; other Building Regulations requirements can still apply where the conservatory isn’t exempt, and overheating is otherwise addressed through design choices like glazing, shading and ventilation.

Does Part O apply to a new-build home that includes a conservatory-style space in the original design?

Yes, in that case the whole dwelling is new residential construction, which is within Part O’s stated scope.

Bottom line

Approved Document O, the Building Regulations guidance on limiting overheating that took effect from 15 June 2022, applies to new residential buildings only, and GOV.UK’s guidance does not extend this to extensions such as a conservatory added to an existing home. A conservatory’s overheating risk is instead managed through design choices and, where relevant, other Building Regulations requirements, not a Part O compliance exercise. This is general information, not advice on a specific project; a designer or building control body can confirm which regulations apply to a particular scheme.

Sources

This guide draws on the following primary sources, current as of 22 September 2026:

• GOV.UK, “Overheating: Approved Document O”

Related guides

Compare Conservatories is an independent guide. We may earn a fee from some links; this never affects what we write. This article is general information, not legal or planning advice on any specific property — always confirm requirements directly with your local planning authority.

GOV.UK guidance on enforcement and post-permission matters confirms a local planning authority has discretionary power to issue an enforcement notice where it believes a breach of planning control has occurred and considers it expedient to act, that recipients generally have 28 days to appeal to the Secretary of State, and that non-compliance once the notice takes effect, with no appeal outstanding, is a criminal offence carrying an unlimited fine.

When a council can issue a notice

A local planning authority has a discretionary power to issue an enforcement notice where it believes a breach of planning control has occurred, for example a conservatory built without the planning permission it needed, and where it considers it expedient to act, having regard to the development plan and other material considerations. This is a discretionary power, not an automatic consequence of every unauthorised structure, so a council can decide the breach does not warrant formal action, though it is not required to reach that conclusion.

The time limits for taking action

Councils do not have an unlimited window to act against operational development such as a conservatory. Current guidance gives a ten-year time limit for enforcement action where the development was substantially completed on or after 25 April 2024, and the previous four-year limit continues to apply where the development was substantially completed before that date. Once the relevant time limit has passed without enforcement action being taken, the development generally becomes immune from enforcement, which is the basis for the lawful development certificate route covered elsewhere on this site.

What the notice must say

An enforcement notice has to let the recipient understand exactly what, in the council’s view, constitutes the breach of planning control, and what steps are required to remedy it or what activities must stop. Guidance requires the notice to be written in plain English and to be accompanied by information about the right to appeal, so a recipient is not left having to work out independently what the council is objecting to or what it wants done about it.

The 28-day appeal deadline

A recipient generally has 28 days to appeal an enforcement notice to the Secretary of State, in effect to a planning inspector. This deadline is applied strictly, without the flexibility that applies to some other planning time limits, so identifying and meeting it is one of the most time-critical steps in responding to a notice, rather than something that can be dealt with at a more relaxed pace alongside gathering evidence or seeking advice.

What an appeal does

Lodging a valid appeal within the deadline suspends the enforcement notice, meaning it does not take effect while the appeal is being decided; the recipient does not have to comply with it, and does not commit an offence, during that period. This gives a genuine practical reason to appeal rather than simply comply immediately, wherever there is a real basis to challenge the notice, since appealing preserves the position while the dispute is resolved.

What happens without a successful appeal

If the compliance period set out in the notice passes without it being complied with, and there is no outstanding appeal, failing to comply becomes a criminal offence. A person convicted faces an unlimited fine, with the court required to have regard to any financial benefit that has accrued or appears likely to accrue from the breach. Separately, the council can use default powers to carry out the required work itself and recover the cost from the property owner, rather than relying solely on prosecution to secure compliance.

FAQs

Is a council required to issue an enforcement notice for every unauthorised conservatory?

No. Issuing a notice is a discretionary power, exercised where the council believes a breach has occurred and considers it expedient to act.

How long does a council have to take enforcement action?

Ten years for operational development substantially completed on or after 25 April 2024, and four years for development substantially completed before that date.

How long is there to appeal an enforcement notice?

Generally 28 days to the Secretary of State, applied strictly with no discretion to accept a late appeal.

What happens if the notice isn’t appealed or complied with?

Non-compliance once the notice takes effect is a criminal offence carrying an unlimited fine, and the council can also carry out the required work itself and recover the cost.

Bottom line

A planning enforcement notice against an unauthorised conservatory has to clearly set out the breach and the required remedy, and carries a strict 28-day deadline to appeal to the Secretary of State; a valid appeal suspends the notice, but failing to comply once it takes effect, without an outstanding appeal, is a criminal offence with an unlimited fine. This is general information, not legal advice on a specific notice; a planning solicitor should be consulted urgently given how strict the appeal deadline is.

Sources

This guide draws on the following primary sources, current as of 22 September 2026:

• GOV.UK, “Enforcement and post-permission matters”

Related guides

Compare Conservatories is an independent guide. We may earn a fee from some links; this never affects what we write. This article is general information, not legal or planning advice on any specific property — always confirm requirements directly with your local planning authority.

Section 49 of the Consumer Rights Act 2015 treats every contract to supply a service as including a term that the trader must perform the service with reasonable care and skill, and section 54 gives the consumer remedies including repeat performance, a price reduction and, alongside these, a claim for damages, where a service does not conform to that term.

The reasonable care and skill duty

Section 49 of the Consumer Rights Act 2015 states that every contract to supply a service is to be treated as including a term that the trader must perform the service with reasonable care and skill. Installing a conservatory is a service within this meaning, so an installer whose work falls below the standard a reasonably competent installer would achieve, rather than simply a matter of taste or a minor snagging issue, has potentially breached this implied term.

What this covers in practice

Because the duty is about how the service is performed, it covers workmanship issues such as poorly sealed joints leading to leaks, a roof or glazing installed out of true, doors and windows that do not close or seal properly, or a base and foundation not built to the standard the job required. It is separate from, though it can sit alongside, product-specific issues with faulty materials or components, which are covered by different consumer protection rules referenced elsewhere on this site.

The remedies available

Section 54 sets out what a consumer can do where a service does not conform to the contract, including the reasonable care and skill term. The primary remedies under the Act are requiring the trader to repeat the performance of the service, or a reduction in the price paid. Section 54 also confirms these statutory remedies do not exclude other options, including a straightforward claim for damages, provided the same loss is not recovered twice through different routes.

Repeat performance first

Repeat performance, essentially requiring the installer to put the substandard work right, is generally the most direct of the section 54 remedies, and giving the original installer a genuine opportunity to correct the problem is usually the sensible first step before considering a price reduction or damages claim, not least because it can resolve the issue without the cost and delay of pursuing a dispute further. Where the installer refuses to return, cannot be contacted, or has already failed to fix the same problem more than once, moving to a price reduction or damages claim becomes the more realistic route.

Keeping evidence

Photographing problems as they are noticed, keeping written correspondence with the installer, and obtaining an independent assessment or repair quote where the installer disputes that the work is substandard, builds the record needed to support a section 54 claim if the dispute cannot be resolved directly. This matters because a dispute about workmanship often comes down to a factual disagreement about the standard actually achieved, which independent evidence helps settle.

If the installer disputes the work

Where an installer disputes that the work is substandard, or does not respond to a request to put it right, the remedies under section 54 can be pursued through the small claims track of the county court for lower-value disputes, without necessarily needing a solicitor. The evidence gathered, photographs, correspondence, and independent assessments, supports a claim at this stage, whether it is resolved through further negotiation or, ultimately, through court.

Where a deposit was paid upfront

A substandard installation dispute often follows a contract where a deposit or stage payments were made before the work was finished, which is a separate factual issue from the section 49 and 54 rights described here, but one that tends to surface at the same time. Whether a deposit was protected, and what the contract itself said about payment stages, is worth checking alongside the reasonable care and skill claim, since it can affect what leverage remains, and how any refund or reduction in price is actually recovered, once a dispute is underway.

Why this matters beyond the immediate fix

A substandard installation left unresolved does not only affect appearance; workmanship issues such as poor sealing or an out-of-true frame can lead to ongoing problems like water ingress or condensation, covered in more practical terms elsewhere on this site, that get worse the longer they are left. Establishing the section 49 and 54 position early, rather than after further damage has occurred, both strengthens the claim and limits how much needs to be put right by the time it is resolved.

FAQs

Does the Consumer Rights Act cover poor workmanship on a conservatory installation?

Yes. Section 49 requires the service itself to be performed with reasonable care and skill, and workmanship falling below that standard can be challenged under the remedies in section 54.

What can be claimed under section 54?

Repeat performance of the service, a price reduction, or, alongside these statutory remedies, a separate claim for damages, without recovering the same loss twice.

Should the original installer be asked to fix the problem first?

Generally yes; repeat performance is usually the most direct remedy, and giving the installer a genuine opportunity to correct the work is the sensible first step.

What if the installer refuses to accept the work is substandard?

The small claims track of the county court is available for lower-value disputes, supported by photographic evidence, written correspondence and an independent assessment.

Bottom line

An installer whose conservatory work falls short of a competent standard has generally failed to perform the service with the reasonable care and skill required by section 49 of the Consumer Rights Act 2015, giving the homeowner remedies under section 54, starting with repeat performance and extending to a price reduction or a damages claim where necessary. This is general information, not legal advice on a specific dispute; Citizens Advice or a solicitor can advise on a claim that cannot be resolved directly with the installer.

Sources

This guide draws on the following primary sources, current as of 22 September 2026:

• legislation.gov.uk, “Consumer Rights Act 2015, section 49: Service to be performed with reasonable care and skill”
• legislation.gov.uk, “Consumer Rights Act 2015, section 54: Right to repeat performance or price reduction”

Related guides

Compare Conservatories is an independent guide. We may earn a fee from some links; this never affects what we write. This article is general information, not legal or planning advice on any specific property — always confirm requirements directly with your local planning authority.

NHBC confirms that during the first two years after legal completion of a new-build home, the builder, not NHBC, is responsible for rectifying problems arising from a failure to meet NHBC’s own building requirements, and that NHBC’s resolution service becomes available only once the builder’s complaints process has been completed.

Why this differs from adding one later

Most of the planning and building control guidance on this site concerns a conservatory added to an existing home, where the homeowner deals directly with an installer and, separately, with building control or a competent person scheme. Where a conservatory is included in a new-build home from the outset, bought as part of the whole property, a different framework applies: the structural warranty the developer arranges for the entire home, commonly an NHBC Buildmark policy, and the process for raising a defect runs through that warranty rather than a separate installer contract.

The two-year builder period

NHBC’s own guidance is specific about where responsibility sits in the period immediately after legal completion: during the first two years, the builder is responsible for rectifying problems arising from the builder’s failure to meet NHBC’s requirements, not NHBC itself. A defect in a new-build conservatory in this window, for example a leak, a sealing fault or an issue with how the space was constructed, is first and foremost a matter for the developer’s own aftercare or customer service team, in the same way any other defect in a new-build home is during this period.

How to report a problem

NHBC’s guidance says a homeowner should contact the builder as soon as reasonably possible after noticing a defect, and always within the two-year builder warranty period, keeping a record of that contact. This record becomes important evidence later if the builder does not resolve the issue and the homeowner needs to escalate to NHBC directly, since NHBC’s process depends on being able to see what was reported and when.

When NHBC steps in

NHBC describes its role as guaranteeing the builder’s obligations under the builder warranty, stepping in only if the builder fails to comply. Before that stage, specific conditions have to be met: the homeowner must have notified the builder within the warranty period, allowed the builder reasonable time to carry out repairs, gone through the builder’s full complaints process, and received the builder’s final written response. Only once these steps are complete does NHBC’s resolution service become available, rather than being a first port of call for any conservatory defect noticed in a new-build home.

The later structural period

After the two-year builder warranty period ends, Buildmark moves into an eight-year insurance period, covering physical damage caused by a failure to build to NHBC’s requirements, generally concentrated on structural elements such as foundations, load-bearing elements and the weatherproofing of the external envelope. A conservatory-related issue arising well into this later period is treated within this narrower, structurally focused part of the warranty, rather than the broader builder warranty process that applies in the first two years, and is less likely to be covered where the issue is cosmetic or a minor fault rather than a genuine structural defect.

Checking which warranty applies

NHBC is one of several structural warranty providers used across new-build housing in the UK, and a home built under a different provider follows that provider’s own equivalent process rather than NHBC’s. Confirming which warranty applies to a specific new-build property, and keeping the relevant policy booklet and certificate, is the reference point for what is and is not covered for that conservatory, rather than assuming the process described here applies automatically to every new-build home.

FAQs

Does NHBC deal with a new-build conservatory defect straight away?

No. NHBC says the builder is responsible for rectifying defects during the first two years, with NHBC’s resolution service acting as a backstop only after the builder’s own complaints process has been exhausted.

What does a homeowner need to do before NHBC will get involved?

Notify the builder within the warranty period, allow reasonable time for repair, complete the builder’s complaints process, and receive its final written response.

Does the later eight-year insurance period cover any conservatory issue?

It is focused on structural defects such as foundations and weatherproofing, so a cosmetic or minor fault arising in this later period is less likely to be the kind of issue it is designed to cover.

Is this the same as the warranty on a conservatory added to an existing home?

No. A conservatory added later is usually covered by the installer’s own guarantee and any insurance-backed warranty, a separate arrangement covered elsewhere on this site.

Bottom line

A conservatory included in a new-build home is generally covered by the same structural warranty as the rest of the property, and under NHBC’s Buildmark, the builder, not NHBC, is responsible for defects during the first two years, with NHBC’s resolution service available only once the builder’s own complaints process has been completed. The later, structural insurance period is framed around defects like foundations and weatherproofing rather than minor faults. This is general information, not advice on a specific policy; the individual Buildmark policy booklet and certificate confirm what applies to a particular home.

Sources

This guide draws on the following primary sources, current as of 22 September 2026:

• NHBC, “In the first two years of the policy”

Related guides

Compare Conservatories is an independent guide. We may earn a fee from some links; this never affects what we write. This article is general information, not legal or planning advice on any specific property — always confirm requirements directly with your local planning authority.

Class 7 of Schedule 2 to the Building Regulations 2010 exempts the extension of a building by a conservatory, porch, covered yard or covered way at ground level where the floor area does not exceed 30 square metres, provided any glazing meets the specified safety requirements.

What Class 7 says

Regulation 9(1) of the Building Regulations 2010, which the legislation marks as applying in England and Wales, says the Regulations do not apply to the erection of any building or extension of a kind described in Schedule 2, or to work on such a building if it remains one after the work. Class 7 in Schedule 2 describes the extension of a building by the addition at ground level of a conservatory, porch, covered yard or covered way, or a carport open on at least two sides, where the floor area of the extension does not exceed 30 square metres.

The exemption has a condition for glazing. For a conservatory or porch that is wholly or partly glazed, the glazing must satisfy the requirements of Schedule 1 that Class 7 identifies, which concern the safety of glazing. Class 7 is limited to extensions at ground level, so an upper-storey addition is outside it, and an extension above 30 square metres is not within the exemption.

Electrics: Part P still applies

Regulation 9(3) says the requirements of Part P of Schedule 1 apply to any extension within Class 7 that receives its electricity from a source shared with or located inside a dwelling. Approved Document P repeats the point, noting that conservatories, porches, domestic greenhouses, garages and sheds that share their electricity with a dwelling are not exempt from Part P. Any new circuit in a conservatory is therefore notifiable, and the work needs certifying.

Water supplies

Regulation 9(2) applies the requirements of paragraphs G1 and G3(2) and (3) of Schedule 1, dealing with cold water supply and hot water safety, to any extension in Class 7 that receives a cold or hot water supply from a source shared with or located inside any building that is not itself of a kind described in Schedule 2. A conservatory kitchenette or sink connected to the house supply would therefore trigger these requirements.

Gas and other rules

Exemption from the Building Regulations does not remove other legal duties. The Welsh edition of Approved Document J notes that Schedule 2 exempts classes of buildings from all Building Regulations requirements, including those in Part J, but that the Gas Safety (Installation and Use) Regulations still apply to exempt buildings. A gas appliance or flue in a conservatory is therefore still subject to gas safety rules.

The exemption also has nothing to say about planning permission, which is decided under a separate system, or about private rights such as covenants.

If the conservatory is not exempt

Where a conservatory falls outside Class 7, the Regulations apply in full. The Welsh edition of Approved Document J explains that in almost all cases of new building work a building control body must be notified in advance, with two exceptions: work carried out by a person registered with a competent person self-certification scheme, and work listed as not notifiable in Schedule 4. It adds that competent person schemes let registered installers self-certify that work complies and that the occupier must then receive a compliance certificate within 30 days of completion.

Checking the position

Because Class 7 depends on floor area, level, glazing and services, the practical step is to measure the floor area of the proposed extension and list what will connect to the house: electrics, water, heating and gas. If any of those connect, some requirements remain, and if the conservatory exceeds 30 square metres or is not at ground level, the full Building Regulations apply and building control needs to be involved.

FAQs

Does a 25 square metre conservatory need building regulations approval?

If it is a ground-level conservatory within Class 7 it is exempt from the Regulations generally, but Part P applies if it shares the house electricity supply, and the glazing condition and water provisions can also apply.

Does the exemption cover a conservatory of 35 square metres?

No. Class 7 applies where the floor area of the extension does not exceed 30 square metres.

Does the same exemption apply in Scotland?

No. Scotland uses building warrants and its own Technical Handbook, and this guide covers England and Wales.

Bottom line

Class 7 exempts a ground-level conservatory of up to 30 square metres from most Building Regulations, provided the glazing meets the specified safety requirements, but regulation 9 keeps Part P electrical safety and certain water requirements in force where services are shared with the house. Gas safety law continues to apply too. This is general information, not advice on a specific project; the local building control body can confirm what applies.

Sources

This guide draws on the following primary sources, current as of 21 September 2026:

• legislation.gov.uk, “The Building Regulations 2010, Schedule 2: Exempt buildings and work”
• legislation.gov.uk, “The Building Regulations 2010, regulation 9: Exempt buildings and work”
• Ministry of Housing, Communities & Local Government via GOV.UK, “Approved Document P: Electrical safety – Dwellings, 2013 edition” (PDF)
• Welsh Government, “Approved Document J: Combustion appliances and fuel storage systems, 2010 edition incorporating 2010 and 2024 amendments” (PDF)

Related guides

Compare Conservatories is an independent guide. We may earn a fee from some links; this never affects what we write. This article is general information, not legal or planning advice on any specific property — always confirm requirements directly with your local planning authority.

Under the Construction (Design and Management) Regulations 2015, a homeowner who commissions building work on their own home is a domestic client, and the client duties normally pass to the contractor on a single-contractor job or to the principal contractor where there are several.

Who is a domestic client

HSE says a domestic client is any individual who has construction work carried out on their home, or the home of a family member, that is not done as part of a business. A client who has construction work carried out in connection with a business is a commercial client. HSE notes that many domestic clients have little or no skill in managing a construction project, which is why CDM 2015 passes their duties to other dutyholders. The Construction (Design and Management) Regulations 2015, known as CDM 2015, apply in Great Britain and place the full client duties on commercial clients.

Where the duties go

Regulation 7 says that where the client is a domestic client, the duties in regulations 4(1) to (7) and 6 must be carried out by the contractor for a project with only one contractor, by the principal contractor for a project with more than one contractor, or by the principal designer where there is a written agreement that the principal designer will do so. HSE says that on a single contractor project the contractor takes on the client’s legal duties on top of their own, which in practice should involve little more than what they normally do to manage health and safety risks.

On a project with more than one contractor, a domestic client who has engaged an architect or other designer can agree in writing that the designer manages the project and takes on the client duties, becoming principal designer. Without that written agreement, HSE says the client duties automatically pass to the principal contractor. If the domestic client fails to make the required appointments, regulation 7(2) makes the designer in control of the pre-construction phase the principal designer and the contractor in control of the construction phase the principal contractor.

What a homeowner still needs to do

HSE stresses that a domestic client does not need skills or experience in managing construction. Provided reasonable enquiries are made of those brought in about their awareness of health and safety risks and their track record in managing them, the client should be able to rely on them. It suggests asking simple questions about track record and allowing enough time and money in the contract for the work to be done safely.

What a contractor must be able to show

HSE says a contractor must be able to demonstrate the skills, knowledge and experience, and for an organisation the organisational capability, to carry out the work safely, and that the level should be proportionate to the complexity of the work and the risks. It gives examples of evidence: records of continuing professional development and training, membership of professional bodies and references from earlier construction work. A contractor that employs others must ensure those individuals are suitably skilled and trained or in the process of becoming so.

Planning, the construction phase plan and paperwork

HSE says details of a contractor’s planning must be recorded as a construction phase plan and that the effort should be proportionate to the project. Under regulation 12, the principal contractor draws up the plan before the site is set up and keeps it under review. The principal designer prepares a health and safety file during the pre-construction phase and, at the end of the project, passes it to the client, or the principal contractor does so where there is no principal designer.

HSE’s notification page adds that where a project is notifiable to HSE and the client is domestic, the notification is made by the contractor or principal contractor, or by the principal designer under a written agreement, and that for a single contractor project the contractor’s name is entered in both roles. The form requires the contact details of the client, principal designer and principal contractor.

FAQs

Is a homeowner responsible for site safety on a conservatory build?

HSE says a domestic client’s duties normally pass to the contractor or principal contractor, although the client should still check the contractor is capable.

Does the homeowner need a construction phase plan?

No. HSE says the contractor records planning as a construction phase plan, and under regulation 12 the principal contractor draws it up where there is more than one contractor.

Does this apply in Northern Ireland?

HSE’s guidance covers Great Britain. Northern Ireland has separate health and safety regulation.

Bottom line

For most conservatory projects, the homeowner is a domestic client whose CDM duties pass to the contractor, but the homeowner can still make sensible enquiries about the contractor’s capability and allow enough time and money for safe working. Regulation 7 sets out where the duties go, and the contractor or principal contractor produces the plan. This is general information, not legal advice; HSE and the contractor can explain how the rules apply to a specific job.

Sources

This guide draws on the following primary sources, current as of 21 September 2026:

• Health and Safety Executive, “Domestic clients: roles and responsibilities”
• Health and Safety Executive, “Are you a domestic client?”
• Health and Safety Executive, “Are you a contractor?”
• Health and Safety Executive, “F10 – Notification of construction project”
• legislation.gov.uk, “The Construction (Design and Management) Regulations 2015, regulation 7: Application to domestic clients”
• legislation.gov.uk, “The Construction (Design and Management) Regulations 2015, regulation 12: Construction phase plan and health and safety file”

Related guides

Compare Conservatories is an independent guide. We may earn a fee from some links; this never affects what we write. This article is general information, not legal or planning advice on any specific property — always confirm requirements directly with your local planning authority.

In England, Class E of Part 1 of Schedule 2 to the General Permitted Development Order allows a building within the curtilage of a house for a purpose incidental to its enjoyment, within limits on height, position, storeys and site coverage, and a separate Building Regulations exemption covers small detached buildings.

Class E covers detached buildings, not extensions

Class E of Part 1 of Schedule 2 to the Town and Country Planning (General Permitted Development) (England) Order 2015 permits the provision within the curtilage of a house of any building or enclosure, or swimming or other pool, required for a purpose incidental to the enjoyment of the house as such, and of an oil or LPG heating container. The government’s 2019 technical guidance says a building attached to the house is not permitted under Class E and falls under Class A, the extension rules that also cover conservatories.

The limits in paragraph E.1

Development is not permitted if it would cover more than 50% of the curtilage (excluding the original house) with buildings, enclosures and containers; if any part would be forward of a wall forming the principal elevation of the original house; if the building has more than one storey; or if its height would exceed 4 metres for a dual-pitched roof, 2.5 metres within 2 metres of the boundary, or 3 metres in any other case. The eaves height must not exceed 2.5 metres. The technical guidance says the 50% limit covers all buildings, including extensions under Class A or with planning permission and existing detached buildings, even ones built before 1948, and that the ban on building forward of the principal elevation extends to a line drawn through that elevation to the side boundary.

Class E also does not apply within the curtilage of a listed building, to a verandah, balcony or raised platform, to anything relating to a dwelling or a microwave antenna, or to a heating container over 3,500 litres. It does not apply to a house that was created only through certain change-of-use rights or that was built under the new-dwellings right in Part 20. The technical guidance adds that decking is allowed if not more than 0.3 metres high.

Extra limits on designated land

Paragraph E.2 says that on land in an area of outstanding natural beauty, the Broads, a National Park or a World Heritage Site, development is not permitted if the total ground covered by buildings, enclosures, pools and containers more than 20 metres from any wall of the house would exceed 10 square metres. Paragraph E.3 says that on land subject to article 2(3) of the Order, no part of the building may be between a side wall of the house and the boundary of the curtilage.

What incidental use means

Paragraph E.4 says a purpose incidental to the enjoyment of the house includes keeping poultry, bees, pet animals, birds or other livestock for the occupants’ domestic needs or personal enjoyment. The technical guidance gives garden sheds, storage buildings and garages as examples but says an incidental purpose does not cover normal residential uses such as separate self-contained accommodation, or using an outbuilding for primary living accommodation such as a bedroom, bathroom or kitchen. A garden room used as living space therefore risks falling outside Class E.

Building Regulations exemptions

Schedule 2 to the Building Regulations 2010 exempts small detached buildings in class 6. A detached single-storey building of up to 30 square metres with no sleeping accommodation is exempt if no point is less than 1 metre from the boundary or if it is constructed substantially of non-combustible material. A detached building of up to 15 square metres with no sleeping accommodation is exempt.

Regulation 9 keeps some requirements in play: Part P applies to a class 6 building that receives its electricity from a source shared with or inside a dwelling, and the hot and cold water safety provisions in Schedule 1 apply if its water is shared with a building outside Schedule 2.

FAQs

Can a garden room be attached to the house under Class E?

No. The technical guidance says buildings attached to the house are not permitted under Class E and fall under Class A.

Can a garden office be used as a bedroom?

Not under Class E. The technical guidance says incidental use does not cover using an outbuilding for primary living accommodation such as a bedroom.

Does Class E apply in Scotland, Wales or Northern Ireland?

No. This guide covers England. The other nations have separate planning rules.

Bottom line

A detached garden room in England can be permitted development under Class E if it stays within the height, position, storey and coverage limits and is used for an incidental purpose, and it may sit outside the Building Regulations if it is a class 6 small detached building. Designated land adds limits, and living accommodation falls outside the class. This is general information, not planning advice; the local planning authority can confirm what applies.

Sources

This guide draws on the following primary sources, current as of 21 September 2026:

• legislation.gov.uk, “The Town and Country Planning (General Permitted Development) (England) Order 2015, Schedule 2, Part 1”
• Ministry of Housing, Communities & Local Government via GOV.UK, “Permitted development rights for householders: technical guidance” (PDF, September 2019)
• legislation.gov.uk, “The Building Regulations 2010, Schedule 2: Exempt buildings and work”
• legislation.gov.uk, “The Building Regulations 2010, regulation 9: Exempt buildings and work”

Related guides

Compare Conservatories is an independent guide. We may earn a fee from some links; this never affects what we write. This article is general information, not legal or planning advice on any specific property — always confirm requirements directly with your local planning authority.

Under the April 2026 domestic Technical Handbook, a single-storey conservatory or porch attached to a house can be built without a building warrant if it is 8 square metres or less, is at least 1 metre from a boundary and has no flue, fixed combustion appliance installation or sanitary facility.

The warrant exemption

The domestic Technical Handbook, April 2026 edition, applies in Scotland only. Its section 0.5 explains that regulation 5 and schedule 3 set out work that can be done without a building warrant, and that such work must still comply with the regulations. Building type 18 in the schedule covers a single-storey building attached to an existing house, ancillary to it, consisting of a conservatory or porch whose glazing complies with regulation 9 and paragraph 4.8 of schedule 5.

The exceptions to type 18 are a building exceeding 8 square metres in area, a building containing a flue, a fixed combustion appliance installation or a sanitary facility, and a building within 1 metre of a boundary. A conservatory outside those limits needs a building warrant, and mygov.scot says it is an offence to start work that needs a warrant without one.

What counts as a conservatory

Appendix A of the Handbook defines a conservatory as a building attached to a dwelling with a door and any other building elements dividing it thermally from that dwelling, and with translucent glazing (including frames) forming not less than either 75% of its roof area and 50% of its external wall area, or 95% of its roof area and 35% of its external wall area. The Handbook notes that the definition was amended on 1 May 2007. The Handbook adds that a conservatory allows natural light and ventilation to be borrowed through glazing and ventilators into adjacent rooms, which is why a large area of translucent material is required in its fabric, and that the definition should be read with the SAP 10 document.

Energy standards

Clause 6.2.11 says a conservatory should be thermally divided from the dwelling, outside its insulation envelope, and the dividing wall, door and window should have U-values equal to or better than the corresponding exposed elements of the house. Where not exempt, a conservatory, heated or not, should meet the same maximum U-values as other new work, except that the glazing and framing forming its walls or roof are unlimited in area, subject to a maximum area-weighted average U-value of 1.8 W/m2K and a maximum for any individual element of 3.3 W/m2K.

Clause 6.1.6 says conservatories under 50 square metres are stand-alone buildings thermally separated from the dwelling, while conservatories of 50 square metres or more subject to standard 6.1 need a non-domestic style SBEM calculation. The Handbook also says some smaller conservatories can be exempt from both a warrant and the standards, and that draught stripping on existing windows and doors between house and conservatory should match that of exposed windows and doors.

Ventilation and daylight

Clause 3.14.9 recommends that a conservatory have ventilators with an opening area of at least one fifth of its floor area, with high-level or roof vents best placed to reduce heat build-up. Where a conservatory is built over an existing ventilator serving a room, clause 3.14.11 says the conservatory’s ventilation must open to the outside air with an area of at least one twentieth of the combined floor area of the room and conservatory, and the room’s ventilator should be at least one twentieth of that room’s floor area. Clause 3.16.2 says a conservatory may be built over a translucent glazed opening if that opening is at least one fifteenth of the floor area of the internal room formed.

Fire spread and escape

Section 2 of the Handbook says short fire resistance duration is sufficient for a conservatory or porch attached to a dwelling even when it is within 1 metre of the boundary. It also says that where a conservatory is located below an escape window, consideration should be given to the design of the conservatory roof.

FAQs

Does a small conservatory in Scotland always avoid a warrant?

No. The exemption in building type 18 is limited to 8 square metres, at least 1 metre from a boundary, with no flue, fixed combustion appliance installation or sanitary facility.

Does the exemption remove the building standards?

No. The Handbook says work not requiring a warrant must still meet the standards required by the regulations.

Do planning rules matter too?

Yes, but they are separate. This guide covers the building warrant and building standards only.

Bottom line

In Scotland, only a small attached conservatory, 8 square metres or less, at least 1 metre from a boundary and without a flue, combustion appliance or sanitary facility, can be built without a building warrant, and even then the standards on glazing, thermal separation, ventilation and fire apply. Larger conservatories need a warrant. This is general information, not advice on a specific project; the local council’s building standards department can confirm what applies.

Sources

This guide draws on the following primary sources, current as of 21 September 2026:

• Scottish Government, “Building standards technical handbook: domestic, April 2026”
• mygov.scot, “Getting a building warrant”

Related guides

Compare Conservatories is an independent guide. We may earn a fee from some links; this never affects what we write. This article is general information, not legal or planning advice on any specific property — always confirm requirements directly with your local planning authority.

In England, Approved Document P says all electrical installation work in a dwelling is subject to requirement P1, and conservatories that share their electricity supply with a house are not exempt from Part P even where the building itself falls within an exempt class.

Part P still applies to an exempt conservatory

Approved Document P (2013 edition, for use in England) says in paragraph 2.1 that all electrical installation work carried out in a dwelling is subject to requirement P1 and should follow the design and installation guidance in section 1, which points to BS 7671. Paragraph 2.2 extends Part P to parts of an installation outside the dwelling and in outbuildings such as sheds, detached garages and domestic greenhouses.

The note to paragraph 2.3 addresses conservatories directly. Schedule 2 to the Building Regulations exempts some small buildings from the Regulations, but the document says conservatories, porches, domestic greenhouses, garages and sheds that share their electricity with a dwelling are not exempt from Part P by virtue of regulation 9(3). Regulation 9(3) itself applies Part P to a Schedule 2 extension in class 7, which includes a conservatory, if it receives its electricity from a source shared with or inside a dwelling.

What counts as notifiable work

Paragraph 2.5 sets out the work that is notifiable under regulation 12(6A): installing a new circuit; replacing a consumer unit; and adding to or altering existing circuits in a special location, meaning the space around a bath or shower, or a room containing a swimming pool or sauna heater.

Paragraph 2.7 says all other electrical installation work is not notifiable, namely additions and alterations to existing installations outside special locations, and replacements, repairs and maintenance anywhere. Paragraph 2.8 adds that installing fixed electrical equipment is within the scope of Part P even if it is connected by a 13A plug, but is notifiable only if it involves work listed in regulation 12(6A). For instance, connecting an electric gate to an existing isolator is not notifiable, whereas a new circuit from the consumer unit to the isolator is.

Three ways to certify notifiable work

Paragraph 3.1 says notifiable work must be certified in one of three ways. First, a registered competent person self-certifies. The installer completes a BS 7671 electrical installation certificate for every job, and within 30 days the installer or the registration body must give the occupier a Building Regulations compliance certificate and give the building control body the certificate or its information.

Second, an installer who is not a registered competent person can appoint a registered third-party certifier before work starts, notify them within 5 days of completion and receive an electrical installation condition report, after which the registration body issues the compliance certificate within 30 days. Third, the installer can notify a building control body before work begins. The body decides how much inspection and testing is needed and may issue a completion certificate, and the document notes that this route can lead to a lower charge where the installer supplies a BS 7671 certificate.

Adding to an existing installation

Paragraph 1.6 explains that when an installation is extended or altered, only the new work must meet current standards, and there is no obligation to upgrade the rest unless the new work adversely affects its safety or the existing installation is in such a state that the new work cannot be operated safely. Paragraph 1.7 says the existing installation should be checked to make sure that the rating and condition of equipment belonging to the consumer and to the electricity distributor can carry the additional load, that adequate protective measures are used and that earthing and bonding are satisfactory. A conservatory that adds sockets, lighting, heating or underfloor heating therefore prompts a check of the consumer unit and the supply.

Information, testing and non-notifiable work

Paragraph 1.2 says enough information should be provided for people to operate, maintain or alter the installation with reasonable safety, including electrical installation certificates or reports, permanent labels on items such as consumer units and residual current devices, and operating instructions. Paragraph 3.13 says non-notifiable work should also be designed, installed, inspected, tested and certificated in line with BS 7671, and paragraph 3.14 warns that local authorities can take enforcement action if non-notifiable work is unsafe and non-compliant. Certificates should normally go to the occupier; in a rented property they may go to the person who ordered the work with a copy to the occupier.

Other nations

This document is for England, and it also applies to building work on excepted energy buildings in Wales. Scotland regulates building work through its own Building Standards Technical Handbook, which lists electrical work among the work in a house that does not need a building warrant while still requiring it to meet the standards.

FAQs

Does an exempt conservatory escape Part P?

No. Approved Document P says conservatories that share their electricity with a dwelling are not exempt from Part P.

Is adding a socket to an existing circuit notifiable?

Not normally. Paragraph 2.7 says additions and alterations to existing installations outside special locations are not notifiable, although the work must still meet BS 7671.

Who receives the compliance certificate?

Paragraph 3.2 says Building Regulations certificates should normally be given to the occupier, or in a rented property to the person ordering the work with a copy to the occupier.

Bottom line

For a conservatory in England, the key question is whether the work creates a new circuit or replaces the consumer unit, since either makes it notifiable and needs certification by a registered competent person, a third-party certifier or building control. Even non-notifiable work must meet BS 7671, and the existing supply must be able to carry the extra load. This is general information, not advice on a specific installation; a registered electrician or the local building control body can confirm the position.

Sources

This guide draws on the following primary sources, current as of 21 September 2026:

• Ministry of Housing, Communities & Local Government via GOV.UK, “Approved Document P: Electrical safety – Dwellings, 2013 edition” (PDF)
• GOV.UK, “Electrical safety: Approved Document P”
• legislation.gov.uk, “The Building Regulations 2010, regulation 9: Exempt buildings and work”
• Scottish Government, “Building standards technical handbook: domestic, April 2026”

Related guides

Compare Conservatories is an independent guide. We may earn a fee from some links; this never affects what we write. This article is general information, not legal or planning advice on any specific property — always confirm requirements directly with your local planning authority.