Do you need planning permission for decking?

Planning permission for decking is required in some circumstances, although this might not be immediately obvious. While decking might seem a relatively innocuous garden design addition, construction could cause some trouble with your local planning department if you fall foul of the planning rules.

Decking can be a great addition to a garden, adding a new outdoor space for dining and entertaining, but planning rules regarding factors such as size and height mean you might need to make a planning application before adding a new decked area.

So, before you make a costly mistake, find out if your decking ideas fall under permitted development (where no permission is needed) or if you will need to submit an application to your local council, with our guide.

Do you need planning permission for decking? 

Many minor improvement works to our homes are covered by permitted development, meaning you do not need to apply for planning permission. Adding decking can fall under permitted development, but there are caveats — the height and size of your decking being two.

"If you are installing decking in your garden, you may need planning permission if your decking is 30cm above ground or more, or covers more than 50% of your garden area, including any extensions or outhouses," advises Allan Jeffrey, Managing Director of Ultra Decking. 

Decking to the front of the house – the 'principle elevation' – may require planning permission too. So may decking which adversely impacts neighbouring homes (i.e. if it creates issues around privacy and overlooking).

Decking height should be measured from the lowest point of ground (even on a sloping plot) to the top of the timber or composite material. (Researching how to build decking will help you work out the finished height of a deck.)  

If you're building on a sloping site or perhaps adding decking where the garden is at a different level to the house, you may find your decking will be above 30cm and as such is considered a 'raised platform' and needs planning.

"If you require planning permission, we would advise for you to directly communicate with your local planning authority, as you are the best person to know what factors make up your project," continues Allan Jeffrey. "While you can ask your supplier for advice, you should not rely solely on them, as you will be the one held responsible if you have not acquired the correct permission necessary."

Homes in designated areas such as national parks or conservation areas, or properties where an 'Article 4 Direction' has been applied, could be subject to further restrictions.

There are other circumstances in which planning permission will be required — adding decking in the garden (or curtilage) of a listed home, for instance, will not be covered by permitted development. 

How big can decking be without planning permission? 

Even if your planned decked area is below 30cm tall, the size of the new outdoor space will also be under consideration. If your decking will cover more than 50% of your garden area (including other additions and outbuildings), you will need to submit a planning application. 

"In national parks the maximum area that can be covered more than 20m from your house is limited to 10m2," adds Allan Jeffrey. 

So, if you're looking to save on decking costs, building within these restrictions should save around £206 on a planning application. 

How high can I build a deck without a rail? 

A deck can be built up to 59cm high without a hand rail, but any decking higher than that will need to install a hand rail of at least 110cm above the decking board to comply with planning permission. 

Tall decks might also require steps, stairs or decking balustrade ideas, which also require Building Regulations approval to ensure safety. 

Why do you need planning permission for decking? 

"When you come to sell your house, you will be asked if you have planning permission for the decking [if required], which can cause complications with the sale of your property if you haven't," explains Allan Jeffrey. "Planning permission is significant for safety and to ensure your property isn’t impacting on the environment or any neighbouring properties." 

If decking has been built over the guidelines without gaining planning permission, homeowners can apply for retrospective planning permission. However, this doesn't guarantee that it will be approved, and if refused, the decking will have to be removed.