Building Regulations: what your house must meet

Your house must meet the Building Regulations as well as its planning permission. Ask your designer which requirements and guidance editions apply before you agree the drawings and specification.

Planning permission decides whether the house can go on that site, at that size and in that style. The Building Regulations set minimum standards for safety, health, energy efficiency and use. A planning grant does not establish that your foundations, escape routes or drainage are adequate. Equally, a design that meets the Building Regulations can still be refused planning permission. See the planning permission guide.

Your building control authority can answer questions about the filing process.

What the regulations are

The main instrument is the Building Regulations 1997 (S.I. 497 of 1997). They have been amended repeatedly since, and later amendments are read together with the original. The rules are written as short, performance-based statements in the Second Schedule, labelled Part A to Part M. Most are a single sentence such as “adequate means of escape in case of fire”, which on its own tells you very little about what to build. The detail comes from guidance.

A second set of rules, the Building Control Regulations 1997 (S.I. 496 of 1997) as amended by the Building Control (Amendment) Regulations 2014, deals with process: the commencement notice, the assigned certifier, inspections and completion certificates. See commencement notice and certification and certificate of compliance on completion.

The Parts, and what each means for a house

This is a plain-language map of the twelve Parts, not the full legal requirements or a construction specification. Most Parts have been amended since 1997. Use the Department’s current amendment index and Technical Guidance Documents with your designer. The original 1997 Schedule alone does not give you the current requirements.

Part	Design checks
A: Structure	Loads must be carried safely to the ground, without impairment from subsoil movement. Check foundations, engineering input, lintels and roof loads.
B: Fire safety	Provide escape routes, suitable internal linings, stability in a fire, protection at external walls and roofs, and access for fire appliances. Check escape windows, smoke and heat alarms, stairs and garage separation.
C: Site preparation and moisture	Keep the ground free of vegetable matter. Address subsoil drainage, contaminants and moisture reaching floors, walls and roofs. Check topsoil removal, damp-proof membranes, cavity trays and radon protection.
D: Materials and workmanship	Use proper materials and carry out work properly. Check product suitability, applicable declarations and markings, and workmanship.
E: Sound	Provide sound resistance between dwellings and adjoining buildings or other parts of a building, and control reverberation in common access areas. Check separating walls, floors and shared access where relevant.
F: Ventilation	Provide ventilation and control condensation. Agree mechanical or background ventilation for an airtight house.
G: Hygiene	Provide bathrooms, sanitary conveniences and a food preparation area. Check the layout and separation of the toilet from the kitchen.
H: Drainage and wastewater	Provide foul and surface-water drainage, including septic tanks where used. Check on-site treatment and soakaways; see wastewater systems.
J: Heat-producing appliances	Provide combustion air, suitable flues, protection against fire and safe oil storage. Check stoves, chimneys and oil-tank positions.
K: Stairs, ladders, ramps and guards	Allow safe passage and protect against falls. Check stair dimensions and balustrades.
L: Fuel and energy	Meet energy-performance requirements through insulation, airtightness, heating and renewables. See nearly zero energy buildings (nZEB) and Part L.
M: Access and use	Make adequate provision for people to access and use the building. Check a level or ramped entrance, circulation space and a ground-floor toilet.

There is no Part I in the current Schedule, which is why there are twelve Parts spanning A to M.

Why the original text is not enough

Changes are not confined to energy and access. There have also been separate amendments for structure, fire, materials, sound, ventilation, hygiene, drainage, heating appliances and stairs. These two topics illustrate why your designer must check the applicable version:

Part L. The 1997 requirement was a single sentence about “the conservation of fuel and energy”. Part L was amended in 2019 to require nearly zero energy (nZEB) dwellings, and again in 2022. Your designer confirms which version applies to your start date. Full detail is in the nZEB guide.

Part M. New dwellings are covered by access-and-use requirements. S.I. 513/2010 introduced the 2012 requirements, subject to transitional provisions. It has since been revoked and replaced by S.I. 608/2022, which retains access-and-use requirements and the exemption for extensions to and material alterations of existing dwellings that do not create a new dwelling. The 2022 text also adds changing-places toilet provisions depending on building use and size; it is not a requirement for every house to have one. Ask your designer which provisions apply to your building. See the fire safety and disability access guide.

Technical Guidance Documents

The Department publishes Technical Guidance Documents (TGDs) alongside the Parts to show approaches to meeting their requirements. Following the relevant guidance is evidence of compliance. An alternative suitable design or construction method is possible, but must still meet the legal requirements. Use the dwelling-house volume of fire guidance where applicable; the separate volume for other buildings is not interchangeable.

What this means for you:

• The built work must actually follow the design.
• Departures are allowed if the designer can show they meet the requirement. Expect more documentation and more scrutiny from the certifier.
• The guidance is revised from time to time. Which edition applies usually depends on when the works commence, and there are transitional rules for projects that already had planning permission when a new edition came in. Do not assume the edition your builder used last year is the one that applies to you.

Who is responsible

Appointing an assigned certifier does not transfer your responsibility for compliance to them. On the statutory certification route, the owner signs the commencement notice, the designer certifies that the design complies, the builder undertakes to build in accordance with it, and the assigned certifier inspects and certifies at completion. Each gives a certificate about their own part. The assigned certifier inspects and coordinates others’ inspections under an inspection plan; they do not continuously supervise every trade. Their certificate does not replace the other parties’ responsibilities or insurance. Your lender and any future buyer’s solicitor may ask for more than the certificate, so ask your lender early what evidence they want.

For an eligible new single dwelling on a single-unit development, the owner may submit an opt-out declaration with the commencement notice. A valid declaration on the public register removes the requirement for an assigned certifier and for the certificate of compliance on completion. The owner must still ensure compliance and submit the applicable plans and builder assignment. Agree professional inspection and compliance evidence even if opting out, and check lender and legal requirements before choosing the route.

The practical consequences are:

1. As owner you remain exposed if the house does not comply, even if you did not do the work. This matters most when you project manage yourself.
2. Carrying out works in contravention of the regulations is an offence under the Building Control Act 1990, and the penalties are set out in section 17.
3. A defect found later does not become the certifier’s problem automatically. That is why a structural defects warranty and the right insurance matter alongside the certificate.

What to do in practice

A short working order for a self-builder:

1. Before design: ask your designer which TGD editions they are designing to, and why. Ask how they will deal with Part L, ventilation (Part F) and radon.
2. Before the commencement notice: agree the certification route and appoint the designer and builder, plus the assigned certifier where required. See architect or engineer and assigned certifier.
3. Before you file: make sure the drawings and specification you file are the ones the builder prices and the lender sees.
4. During the build: agree inspection hold points with your appointed professional for anything that will be covered up: foundations, drainage, insulation, airtightness, fire stopping.
5. Before completion: collect test results, product certificates and the as-built drawings. Agree the records needed for the applicable completion process, final Building Energy Rating (BER), lender and handover.

Common mistakes

• Starting because planning permission was granted, without meeting the commencement-notice requirements and notified start date.
• Treating the certificate as a formality and not agreeing inspection hold points in the building contract.
• Relying on an old TGD edition, for example for energy performance, because the builder has used it before.
• Forgetting that drainage and wastewater (Part H) interact with the planning conditions and the site suitability assessment. See site suitability.
• Changing the design on site without telling the certifier. Significant changes may need an updated filing.

Questions to ask

• Designer: which guidance editions apply, and are there any deliberate departures?
• Certifier: which Parts need particular attention on this site? At which stages must work pause for inspection before it is covered? These are the inspection hold points.
• Builder: which documents are you signing, and what happens if the drawings change?
• Building control authority: how long are commencement notices taking to validate? What documents are needed if the house includes a granny flat or separate unit?

For how these tasks fit the whole project, see the stages of a self-build.