Building conversions
Converting a building or space—such as a loft, garage, or barn—usually needs Building Regulations approval. This makes sure the new space is safe and suitable to use.
Building Regulations check things like:
Strength and stability – making sure floors, walls, and roofs are safe (Approved Document A)
Fire safety – including safe escape routes (Approved Document B)
Insulation and energy use – helping keep the space warm and efficient (Approved Document L)
Ventilation and damp protection – keeping the air fresh and preventing moisture problems (Approved Documents F and C)
Sound insulation – reducing noise between rooms or homes (Approved Document E)
You can find more detail about these requirements in the Regulatory Guidance section of our website, including:
- Fire & Structural Safety
- Energy, Air and Sustainability
- Water, Drainage and Hygiene
- Fabric & Performance
- Access & Inclusive Design
- Heating & Building Services
Even if you don’t need planning permission, you will still usually need Building Regulations approval.
We can review your plans and visit the site at key stages to check the work and help make sure it meets the regulations.
Electrical work (Part P)
If you are carrying out electrical work in your home, it must comply with Part P of the Building Regulations.
Part P helps keep people safe by making sure electrical work is designed and installed correctly. This reduces the risk of electric shock, fire and injury.
What is notifiable electrical work?
Some types of electrical work must be reported under the Building Regulations. This is called notifiable work.
Examples include:
- Installing a new circuit
- Replacing a consumer unit (fuse box)
- Rewiring all or part of a property
- Adding to or changing an existing circuit in a special location, such as a bathroom or outdoor area
- Supplying power to a garage, shed, garden office or other outbuilding using a new circuit
Most minor electrical work is not notifiable. Examples include:
- Replacing sockets, switches or light fittings
- Repairs and maintenance to existing electrical installations
Not sure?
As part of your Building Regulations application, you will be asked whether any electrical work is being carried out and whether that work is notifiable. We need this information before we can accept and process your application.
If you are unsure, we recommend checking with your electrician or contractor before you submit your application. Confirming this information can help avoid delays, extra fees and the need for us to contact you for more details.
If you need help, please contact us.
How do I comply with the regulations?
You have two options.
Option 1 – Use a Part P registered electrician
A Part P registered electrician can certify their own work and notify it through their Competent Person Scheme.
If you use a Part P registered electrician, they will:
- Carry out the work in line with the Building Regulations
- Notify the work on your behalf
- Provide an Electrical Installation Certificate for the work completed
- Arrange for a Building Regulations Compliance Certificate to be issued to you, usually within 30 days of the work being completed
How do I find a Competent Person
You can use the LABC Frontdoor – Find a Competent Person search tool.
Option 2 – Apply through Building Control
If your electrician is not Part P registered, you must submit a Building Regulations application before work starts.
Building Control will inspect the work and may charge an additional fee for this service.
More information
You can find further guidance on electrical safety in homes in Approved Document P (Electrical Safety – Dwellings).
Heating systems
Installing or replacing a heating system, such as a boiler, radiators, or underfloor heating, must meet Building Regulations. This helps make sure it is safe and works efficiently. The rules cover:
Energy efficiency – so the system uses less energy and keeps heating costs down (Approved Document L)
Safety – including the safe installation of gas appliances (Approved Document J)
Ventilation and flues – making sure air supply and fumes are dealt with safely (Approved Document F)
You can find more information in our Energy, Air and Sustainability guidance, including the section on Combustion Appliances & Fuel Storage Systems.
Many heating systems can be installed by registered professionals, such as Gas Safe engineers, under a Competent Person Scheme. This means they can confirm the work meets the regulations and give you a certificate.
If you use an installer who is not registered, you will need to apply to Building Control for approval.
How do I find a Competent Person
You can use the LABC Frontdoor – Find a Competent Person search tool.
Windows and FENSA
Replacing windows or doors must meet Building Regulations. This helps make sure your home is safe, energy efficient, and comfortable.
The rules cover:
Energy efficiency – keeping heat in and reducing energy use (Approved Document L)
Safety glazing – using the right type of glass in certain areas to prevent injury (Approved Document K)
Ventilation – making sure there is enough fresh air (Approved Document F)
You can find more detail in our guidance pages, including Energy, Air and Sustainability and Fabric & Performance.
You have two options:
- Use a FENSA-registered installer (or similar scheme), who can confirm the work meets the rules; or
- Apply to Building Control for inspection
A FENSA installer will:
- Register the work with the council
- Give you a certificate to show it complies
This certificate is important, especially if you decide to sell your property.
How do I find a Competent Person
You can use the LABC Frontdoor – Find a Competent Person search tool.
Garden Walls & Boundaries
Building or changing walls, fences, or boundaries may need Building Regulations approval in some cases. This depends on things like:
- Height and strength – making sure the wall is safe and stable
- Location – especially if it is near a road, pavement, or public space
- Retaining walls – walls that hold back soil or ground must be strong enough to prevent collapse
Smaller or simple works may not need approval. However, it’s important to check before you start.
We can advise you on whether your project needs an application and what you need to do next.
Competent Person Schemes
Competent Person Schemes let qualified tradespeople confirm that their work meets Building Regulations without needing extra approval.
This usually covers work like:
- Electrical jobs
- Gas and heating systems
- New windows and doors
- Roofing, insulation, and plumbing
Why this helps:
- You don’t need to apply separately to Building Control
- The process is quicker
- It can cost less overall
What the installer must do:
- Be registered with an approved scheme
- Tell the scheme when the work is finished
- Give you a certificate to show the work complies
How do I find a Competent Person
You can use the LABC Frontdoor – Find a Competent Person search tool.
Party Wall Act
The Party Wall Act 1996 comes into play if your work could affect a shared wall or the boundary between your property and a neighbour’s. This might include things like:
- Cutting into a shared (party) wall
- Building right up to, or on, the boundary line
- Digging close to a neighbouring building
In these situations, you’ll usually need to:
- Let your neighbours know about the work in advance
- Reach an agreement with them (called a Party Wall Award)
This process is separate from Building Regulations, so you may need to deal with both.
While we can guide you on Building Regulations, party wall matters are handled under a different process. You may wish to seek advice from a party wall surveyor or other specialist if you’re unsure how the Act applies to your project.
Visits and Inspections
Building Control surveyors visit your site at key stages of your build. These checks make sure the work meets Building Regulations and is safe and sound.
Typical inspections include:
Foundations – checking the size, depth, and ground conditions before concrete is poured
Damp proof course (DPC) – making sure protection against moisture is in the right place
Structural elements – such as beams, walls, and load‑bearing parts
Drainage – checking pipes and connections before they are covered
Completion – a final check when the work is finished
We aim to provide prompt inspections, clear advice, and follow‑up email reports after inspection visits. This helps keep dutyholders informed and fix issues early, before they become bigger problems.
For more detail on each stage, see the Inspection stages for my project section and For more detail on each stage, see the Inspection stages for my project section. You can also visit What Inspectors Look for at Key Stages for further guidance.
Please note: the information provided is general guidance only. It is not a full or definitive interpretation of the Building Regulations. Every project is assessed on a case‑by‑case basis, and requirements may vary depending on the type of work and site conditions. Compliance will always be based on the specific details of your proposal.
To get ready for a visit, go to Prepare for an inspection.
When you’re ready, Book an inspection online.
Timescales and Completion
Key points to know:
- Work can usually start 48 hours after you submit a Building Notice.
- With a Full Plans application, your plans are checked and approved before work begins.
- You must book inspections at the right stages of your project.
How long will my project take?
Every project is different. Timescales depend on the size and complexity of the work, how well it is planned, and how smoothly it runs on site.
For Full Plans applications, there is usually a decision period of around five weeks once your application is valid. If needed, this can be extended with your agreement.
To help avoid delays:
- Make sure all paperwork is complete and accurate so your application can be validated quickly
- Ensure prompt payment of fees
You may also find our Managing Your Application and Building Control Process: A Quick Guide pages helpful, as they explain what to expect and how to keep things moving.
Once work starts, you can help keep your project on track by:
- Asking us to inspect — we will attend site as soon as possible
- Calling before 9:30am if you need a same-day inspection
- Making sure dutyholders (such as your builder or designer) are available on site
- Reading and acting on inspection reports promptly
You can also refer to our guidance on how to prepare for inspections, which includes simple steps to help avoid delays.
Completing your project
When your work is finished, you must:
- Tell us that the project is complete so we can carry out a final inspection
- Ensure all required dutyholder forms are completed and returned
Once your project meets all building regulations, we will issue a Completion Certificate. This certificate is important, especially if you plan to sell your property in the future.
Ground Investigation Reports
Do I need a ground investigation?
Not every project needs one. You are more likely to need a report if you are:
- Building a new property
- Adding an extension where the soil is unknown
- Working on land that may be contaminated
Sometimes this work is already carried out as part of a site investigation for planning permission. If a report is needed for your building control application, we will discuss this with you. We may ask for this information to make sure your building is safe and properly designed.
What does a report include?
Ground investigations can involve on-site testing, such as:
- Taking soil samples
- Digging trial pits
- Drilling boreholes
The report will usually check:
- The type and strength of the soil
- Water levels and drainage
- Whether the ground is suitable for your foundations
How much does it cost?
Costs can vary depending on the size of the site and the level of testing needed. Simple investigations cost less, while more detailed surveys will cost more.
Speaking with your designer or contractor can help you decide if one is needed. Getting the right information early can help avoid problems, delays, and extra costs later on.
Finding a specialist
Ground investigations are carried out by specialists who check that the land is safe and suitable to build on. They are often referred to as Geoenvironmental Consultants or Geotechnical Consultants. Their role is to make sure the ground is safe and stable, strong enough for your building and free from any hidden issues, such as contamination.
You can find qualified companies by:
Speaking to your designer, architect, or builder for recommendations
Searching using the Association of Geotechnical and Geoenvironmental Specialists directory: www.ags.org.uk/directory/
Visiting the Geological Society website (www.geolsoc.org.uk)
Noisy & Disruptive Building Work
Building Control does not cover these types of issues and cannot investigate or take action on noise complaints, as our role is limited to building safety and compliance.
If you feel comfortable, it’s often helpful to speak with your neighbour or the contractor first. Many concerns can be resolved quickly with a simple conversation.
General Construction Working Hours
These hours usually apply to larger building projects (not small DIY or occasional work):
8:00am – 6:00pm Monday to Friday
8:00am – 1:00pm on Saturdays
No work on Sundays or Bank Holidays
Please note that permitted working hours can vary depending on the council. It’s best to check your local authority’s website for the exact rules in your area.
Noise and Disturbance
Building work can sometimes cause noise or disruption, which may be considered a nuisance depending on the situation and its impact on people nearby. If you have concerns, you should contact your council’s Environmental Health team for advice or to report the issue.
Visit your council’s website for details on Environmental Health and how to report an issue; if you’re not sure which council to contact, visit: www.gov.uk/find-local-council. You can also find general advice at www.citizensadvice.org.uk
