One of the cost-effective ways to add more living space in your house is through a single-storey extension. In this way, you do not need to move house. Furthermore, it provides an excellent opportunity to layout additional space that suits your home. You can add a light-filled space linked to your garden, which can increase the value of your property.

Cost of Single Storey Extension

The first step before planning any extension is to set your budget and to make sure that you can afford it. The breakdown of the build cost is as follows:

Well, for a simple single storey house extension, expect to pay around £1500 to £2000 per square meter. But if you want good quality material, then it can cost you between £2000 and £2500 square meter. The cost can get even higher for a high-spec extension. Some other factors can add up to the build cost, which is as follows:

• First, you are going to hire an architectural services provider who will help you with planning permission and drawings.
• If the extension requires changing the structure, then you will need the help of a structural engineer.
• In some cases, you need to hire a surveyor which costs between £500 and £1500.
• The project manager will charge a fee of 3-7% of the build cost. You can also ask them about their hourly or daily rate. But if you are sure that you can manage on your own, then you can save some money.
• VAT (Value added Tax)
• You also need to get planning permission, and an application cost is £206.
• Another fee that you need to pay is building control charges which depend on the size of the extension. You also need to pay a party wall agreement which can cost from £700 to £100 per neighbour.
• You also will need to pay additional fees such as tree report, flood risk assessment, ecology report, archaeological report, historic building report, etc.

Cost of Fitting Out Single Storey Extension

What is the cost of fitting out a single-storey extension? It depends on the type of room. Adding a kitchen is expensive than a home office so that the price can vary depending on the size and nature of the room.

• If you are planning on adding a kitchen, then it can cost between £5,000 and £30,000.
• Adding another bathroom can cost between £4,500 and £10,000. It depends on the quality of the fittings.
• You also need to add an extra £25 to £100 per square meter for flooring.
• Another thing that adds up to the cost is heating. Extending an existing heating system is not difficult and requires only two days, which can be done by a plumber. But if your house has underfloor heating, then it can cost more because it may need an additional boiler to cope with demand.

Do You Need Planning Permission for A Single Storey Extension?

If your single-storey extension is within the permitted development criteria, then you do not need planning permission. You will need planning permission if:

• The extension requires more than half the area of land.
• You want to extend towards the road.
• You are going to increase the height of the building.
• It needs to extend 6m from the rear of an attached house.
• It needs to extend 8m from the read of a detached house.
• The extension is greater than the width of the house.
• You want to extend the balcony or veranda.

The architectural services provider is well aware of the limitations and can help you with that. If you do not require planning permission, then it is good to apply for a certificate of lawful development from the local council.

Do You Need to Comply with Building Regulations?

No matter what type of house extension; you need to comply with building regulations. For this, you need to apply to your local building control department. When it comes to the cost, each authority has its own rates. Some builders are building control certified; they do not require this certificate to carry out work.

Party Wall Agreement

You may or may not need a party wall agreement, depending on your relationships with your neighbours. Talk with them and show your plans, maybe they will sign the party wall agreement wavier form. You can also hire a surveyor for this task, but if your neighbour is not happy, then he or she can employ their surveyor.

How Big Your Extension Can Be?

The size of the house extension depends on how much your house has already been extended. But if the extension is reducing the size of the garden, then it is not good for the desirability of your property. If the extension is within permitted development criteria, then you do not need planning permission.