Last updated on November 15th, 2022
Side return extension cost guide
This is a great option for terraced houses in particular, which often have narrow side returns that can’t really be used for anything else.
In this guide, we’ll take a closer look at the average side return extension cost. This includes the cost of adding a new kitchen in your new extension, plus other cost considerations to bear in mind.
How much does a side return extension cost?
The total cost of a side return depends on three key factors – the size, the quality and whether you want a single or double-storey extension. The cost may also be greater depending on where you live. For example, prices in London can be higher than the rest of the UK.
|Type of side extension||Low cost||High cost||Average cost|
|Small, single-storey side return extension cost||£30,000||£45,000||£37,500|
|Small double-storey side return extension cost||£45,000||£65,000||£55,000|
|Side return kitchen extension cost||£5,000||£14,000||£9,500|
|Side return extension cost per m2||£1,500||£4,500||£3,000|
|Glass side return extension cost per m2||-||-||£3,000|
Our costs are ballpark averages – get a local tradesperson to quote now
But generally speaking, the average cost of a side return extension is between £30,000 – £65,000.
Side return extension extension cost per square metre
The cost per square metre for a side return extension varies according to the same criteria as above. Outside London, the cost is typically between £1,500 – £2,400 per square metre and in London, it can be as expensive as £4,500 per square metre.
Glass side return extension cost
Glass extensions can be more expensive than traditional brick extensions; typically costing around £3,000 per square metre. This is generally because they’re more complicated to install.
Cost of side return extension – Victorian terrace
Victorian terraces are common in many cities and towns in the UK, and they often have one thing in common – narrow side returns.
If you’d like to extend yours, you can add a single-storey extension for around £37,500 and a double-storey extension for £55,000. The latter could represent better value for money, but remember that the type of roof could affect the total price.
Side return kitchen extension cost
One of the most popular reasons to get a single-storey side return extension is to improve the size and quality of the kitchen.
If you’re planning a side return kitchen extension, you’ll need to take two different costs into account. The first is the extension itself, which costs on average £37,500 depending on the size.
Then you’ll need to factor in the cost of buying and installing a new kitchen, which could be around £9,500 depending on the specification. In total, you could be looking at a bill of around £47,000 for the project.
How long does it take to build a side return extension?
It should take around three to four months to build your new side return extension. However, the total project length could be longer if you need to seek planning permission or other approvals.
Do I need planning permission for a side return extension?
If your extension is small enough, it may be covered under Permitted Development. This means that there’s no need for planning permission, although it will still need to meet building regulations. You may also need a party wall agreement if your extension is adjoining a wall on your neighbour’s property.