The Modexa Build guide to building regulations and planning permission

What are building regulations and what is planning permission?

These are two separate entities, the need for which are governed by two separate areas of legislation. One does not exempt the other – they need independently considering.

Essentially, Building regulations are concerned with the specification of a building. This includes the safety, robustness and technical aspects of any construction project. Will the building meet fire and escape regulations? Is it sufficiently protective for its use? Has the building been planned with energy efficiency in mind?

However planning permission will allude to a building’s appearance. Does it fit in with the environment? Does is complement the area and buildings around it? Will it impact negatively on the ‘feel’ of a particular space?

When it comes to planning permission, the phrase ‘Permitted Development’ or ‘PD’ refers to a building that does not need planning permission.

Building Regulations: A mandatory requirement

First and foremost, it is mandatory that building regulations approval is secured before embarking on any project, especially one that requires structural work such as a modular extension. The process means that an inspector will want to visit the site and, ultimately, issue a completion certificate.

Full plan or building notice?

Before embarking on your project, you will need to decide between full plan or building notice.

The Full plan route will ensure that your project will meet regulation approval from the outset.

The building notice route, which is more suitable for less complex projects, will require you to stick to regulations throughout the build process.

Local Authority or private inspection?

Yours is the decision in terms of whether you commission your local authority or a private inspector with the task of building approval. Using a private inspector should decrease the timescale of the project, but may cost a premium.

Get a trusted partner to know your project!

Modexa Build pride ourselves on an intimate knowledge of the projects that we are involved in. Because you are ultimately responsible for the project meeting compliance requirements, we will be your de facto compliance managers. We’re here to track progress against plan, manage site inspections, assure compliance and, ultimately, achieve a successful completion certificate.

Building Regulations and size/ purpose

Many extensions or garden rooms/ annexes do not require building regulations if:

• The floor area is under 30m²
• It is not used for sleeping
• It is substantially separated from the house

However, building regulations may apply if it includes:

• Plumbing
• Sleeping accommodation
• Electrical work (Part P)
• Heating systems

On sale…

When it comes to sale, a conveyancer will want to know that all approvals are in place. If not, you will potentially be faced with a costly insurance indemnity.

In order that your sale is not held up, or faced with additional costs, you must have a certificate of completion in place for any building works.

Planning Permission

In the UK, most extensions, garden rooms and annexes can be built without planning permission because they fall under permitted development (PD) — but there are a few rules you must stay within.

1. Permitted Development Rules (No Planning Permission Required)

An extension normally does NOT need planning permission if it meets these conditions:

Location

• It must be behind the front wall of the house (i.e. in the back or side garden)
• It cannot be in front of the house facing the road

Height limits

• The building must not be higher than 2.5m if the building is within 2m of the boundary

If it more than more than 2m from the boundary:

• 4m is the maximum height for a dual-pitched roof
• 3m is the maximum height for a flat roof

Size

• Outbuildings must not cover more than 50% of the land around the house (excluding the original house footprint).

Solar Panels

• Installing solar panels on your extension or garden room will likely fall under the PD rules, and as such should not need planning permission.

Use

• Use of the new building must be incidental to the main house

Examples allowed:

• Garden office
• Gym
• Studio
• Games room
• Storage

Not allowed under Permitted Development Rules:

• A separate living accommodation, for example a granny annexe
• A self-contained rental unit
• A full kitchen and bathroom used as a dwelling

2. Extra Restrictions

Planning permission may be required if:

• The property is a listed building
• It is in a protected areas such as a conservation area, or area of outstanding natural beauty
• It is a flat or maisonette
• The garden room is used as a separate dwelling

3. The Common “Developer Safe” Specification

A lot of builders stick to the following specification because it avoids planning:

• 2.5m overall height
• Within 2m of boundary
• Under 30m² total build area
• Flat roof

As a result, this is basically the standard garden room spec used across the UK.

For more detailed information on these processes, speak to us at Modexa Build, take a look at your local planning authority website and/ or the government’s planning portal. This is particularly important as regulations and permissions do change over time, and during certain economic and political climates.

Building Regulation FAQs

Does a conservatory conversion require building regulations?

Since a conservatory conversion is replacing an existing structure, it is unlikely that building regulation approval will be needed

Planning Permission FAQs

Does a Granny Annexe require planning permission?

Yes; since a granny annexe (or in fact a maisonette or apartment) is a self-contained unit, permission will be needed to cover the additional safety features of a stand-alone property.

Do I need planning permission for a 4m extension?

No, as long as it is s a straightforward 4 m extension at the rear of your house