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.