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Building Regulations: Your Complete Guide

Building Regulations Guide UK
(Image credit: Getty Images)

Traditionally, Building Regulations were introduced to ensure that new buildings were structurally stable and safe to live in without risking life and limb.

Today, by law, most construction work needs to be carried out in accordance with Building Regulations whether you have applied for planning permission or not.

However producing detailed construction drawings can be a bit of a grey area that sometimes gets overlooked, risking serious problems occurring further down the line.

Where as planning approval may be more subjective, Building Regulations are largely objective. An application for Building Regulations either conforms to those regulations and is approved, or fails and is rejected.

Below is everything that you need to know.

(MORE: 23 Thing You Can Do Without Planning Permission)

When Do I Need Building Regulations Approval? 

You will require Building Regulations approval if you intend to carry out any new structural work or alterations to your home.

Additionally, work involving these areas also requires approval, although in some of these cases, competent persons can self-certify their works for compliance:

  • Drainage
  • Heat-producing appliances
  • Cavity wall insulation
  • New electrics

What Building Regulations Do I Need to Comply With? 

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The main exemptions for Building Regulations are peripheral things like small porches, conservatories or detached garages (up to 30m2 floor area). 

So once you’ve secured your planning approval, the focus needs to shift to proving that your design ticks all the right technical boxes.

The Approved Documents of the Building Regulations comprise of a series of detailed guidance manuals (ranging from A to R) covering everything from structure and fire safety through to security and electronic communications. 

The Regulations are very detailed, and can be read in full on the Communities and Local Government website.

In brief, your project will have to comply with these areas:

  • Part A – Structure
  • Part B – Fire Safety
  • Part C – Contamination and damp
  • Part D – Toxicity
  • Part E – Sound
  • Part F – Ventilation
  • Part G – Hygiene
  • Part H – Drainage
  • Part J – Fuel
  • Part K – On-site Safety
  • Part L – Conservation of Fuel and Power
  • Part M – Access
  • Part N – Glazing
  • Part P – Electrics

You will need to appoint a building inspector, who will ensure that your project meets Building Regulations. 

(MORE: Find a building regs expert in your area)

Building Regulations Guide UK

(Image credit: Getty Images)

Do I Need Building Regulations Approval for an Extension? 

There’s no point commissioning expensive technical drawings before planning consent has been granted

If you are building an extension then you will most likely need Building Regulations.

Most extensions will need to meet a minimum set of technical standards.

These are likely to be:

  • Energy performance (ensuring your build is insulated enough and has good airtightness so heat doesn’t just leak out)
  • Structural integrity as most extensions require foundations
  • Protection against falls and unsafe walls  
  • Electric and gas safety as most extensions require new systems
  • Fire protection which means ensuring there is safe passage from your home to a safe external area

How Much Does a Building Regulations Application Cost? 

Most local authorities offer fee calculators on their websites. Their fees will depend on several factors including the type of work involved, size of the project and number of visits required. Private companies will negotiate their fees directly with you.

In England, Wales and Northern Ireland, once an application is lodged, work can commence on site within 48 hours.

Remember, on top of application fees, you will need to budget for plans and structural calculations which can come in between £1,200 - £4,000 plus depending on the scale of your project. 

Building Regulations Guide UK

(Image credit: Getty Images)

Types of Building Regulation Applications

Before any work can begin, you need to decide whether to make a Full Plans or a Building Notice application.

With a Building Notice, it is possible to carry out the work without prior approval while a Full Plans application is where you submit plans and documents to be approved.

(MORE: Find a Builder)

What is a Full Plan Application?

For most construction projects a Full Plans application is made to building control. 

If you choose a Full Plans application, you will know from the start that the working drawings have been checked and approved by the building inspector and that the plans fully comply with all of the Building Regulations.

Importantly, this means that any issues regarding non-compliance with the regulations can be thrashed out before building work actually starts. 

The application comprises of: 

  • A full description of the proposed works 
  • A set of technical drawings
  • Structural engineer’s calculations 
  • A location or 'block' plan  

Building Regulations Guide UK

(Image credit: Getty Images)

What is a Building Notice Application?

The Building Notice method is not allowed if you’re proposing to build over, or close to, a public sewer

With this method you’re basically promising in advance that you’ll comply with the Building Regulations on site. 

This might be feasible for some small domestic alterations or a very simple home extension but it’s harder for larger projects.

If your site inspections uncovers stuff that contravenes the regulations while it’s being built, such as the wrong type of insulation or too much glazing work has to be stopped or re-constructed which could prove disruptive, as well as costly.

Remember you still need to complete a form giving details of the building work together with a site plan (1:1250 or 1:12500 scale) showing the boundaries of site and drainage details. 

You may also be asked to provide marked up sketch drawings (typically copies of those used for planning) together with structural engineer’s calculations and energy performance details.

(MORE: Internal Wall Insulation)

Will I Need a Structural Engineer? 

The plans required for building control are considerably more detailed than those submitted for planning, and are often commissioned as an additional service.

Whether you choose to submit a Full Plans application or not, building control normally require calculations from a qualified structural engineer who you can employ at the structural drawing stage.

What’s more if you plan to make any structural alterations to your existing house, such as knocking down internal walls and openings, these may also need calculations.

Depending on the size and complexity of the project, and whether site visits are needed, engineer’s fees typically range from around £400 for run-of-the-mill extensions to £3,000 plus for more complex houses.

How Much do Building Regulation Drawings Cost?

Added Costs

Large architectural practices can charge £75 or more per hour for this sort of work, and producing detailed technical drawings with a specification for a bespoke new house could set you back as much as £10,000

For Building Regulation drawings, expect to pay from around £700 for a single-storey extension, and around £1,200 for a two-storey extension, excluding additional charges for structural calculations, building control application fees and any party wall agreements.

LABC fees are published on local authority websites and typically cost around £1,000 for a new house but less than half that for an average extension or loft conversion. 

In total, for the average new house you could expect to pay around £2,000, less if planning drawings have first been commissioned as there’s a certain amount of overlap.

(MORE: How to Add a Single-Storey Extension)

Building Regulations Timeline

This depends on how busy your designer is. A reasonably straightforward job shouldn’t take much more than three or four days. If the engineer’s calculations are holding things up, it’s normally possible to save time by submitting them after your main application.

For building control to process a Full Plans application the stipulated period of five weeks should be sufficient assuming there are no major issues.

Remember, you don’t have to wait for ‘plans approval’ before starting work on site.

(MORE: Find an Architect)

Who Grants Building Regulations Approval?

You can choose to use:

  • A local authority inspector from your local council and run through Local Authority Building Control (LABC)
  • An approved inspector from a government-approved private building inspection company. Around 20% of all approvals are now handled privately, without recourse to the local authority

This is the case for those that self build, as well as all manner of projects such as renovating a house, extensions and loft conversions.

Approved inspectors are registered with the Construction Industry Council. They must re-register every five years to maintain high standards.

A building inspector appointed through LABC and an approved inspector will carry out the same duties for a self-builder. They will check plans for compliance when a full plans application is made, and carry out site inspections when requested to check work on site at various stages. 

However, only an inspector from your local authority has powers of enforcement. An approved inspector must hand the project over to the local authority if there are problems with the project that cannot be resolved informally.

The Inspection Process

Although work on a new build or extension may proceed before any formal approval, nothing can proceed beyond the inspection stages without the approval of the inspector. 

Those inspection stages are:

  • Excavations for foundations
  • Foundation concrete
  • Oversite
  • Damp-proof course
  • Foul water drains trenches open
  • Surface water drains trenches open
  • Occupation prior to completion (second fix)
  • Completion

Completion Certificate

When the building is completed to the satisfaction of the inspector, a Completion Certificate will be issued. This is a vital document that must be retained alongside the written planning permission for use if you ever want to sell.

It is also required in order to release final funds from lenders, obtain the warranty certification and in order to reclaim VAT (if applicable).

The completion certificate will not be available until all your certificates have been passed to the building control officer and a final site inspection has passed.

The relevant certificates vary from one project to another but usually include:

  • Electrical safety
  • SAP rating
  • Air pressure test
  • Boiler installation and hot water services
  • Water efficiency calculations
  • Security
  • Fuel storage
  • Remediation of contaminated land
  • Chimneys and open flued appliances.