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🕑 6 minute read
Building an extension is one of the best ways to leave your mark on your home. It could even add more value to the property when it comes to selling up.
However, it takes more than just finding the right contractor to arrange an extension. A lot of planning happens before work begins and you’ll need to consider permissions, budgets and timelines before moving forwards.
Where to start when building an extension
Firstly, you need the right builder on board to help arrange your building extension. Many building firms specialise in extensions and can take care of everything from laying the bricks to fitting out the interior.
You should also find a tool hire company in your local area. You may need a digger, cement mixer, a skip and plenty of other equipment to build an extension. Your builder should be able to advise here.
When it comes to building an extension on a house, there are plenty of options – most of which will have planning permission considerations. The most common types of extension include:
In most cases, you’ll need planning permission to build an extension. Planning permission is the green light from your local council to go ahead with the construction.
There are many reasons why planning permission is required, primarily to ensure your extension can be built safely and securely. Without it, your local council are within their rights to halt your extension and order the removal of any building work already constructed.
To get planning permission, you’ll need to contact your local planning authority (LPA) through your local council. You can also use websites such as Planning Portal to start, view and submit your application online.
Once the council has your application, they will look at your proposed project and make a judgement on whether to approve it or not. This includes exploring factors such as:
For smaller projects, you may not need planning permission beforehand. This is because it might fall under the government’s ‘permitted development rights’. Speak to your builder or LPA to check this.
As with most things, the cost of building a home extension depends on several factors, including the:
For example, a single storey extension in London can cost around £2,200 to £3,300 per square metre.
For more complex projects, like a basement conversion, costs can vary depending on the level of work and use. You might need to consider things like lowering the floor level, digging a new space and creating an access point.
Outside of construction costs, you’ll also need to consider factors such as:
There are all sorts of potential pitfalls when building an extension. Fortunately, it’s easy to plan for most of them.
These are some of the things you should consider before embarking on an extension project.
Architects and structural engineers can be expensive. But if you want a job done right, it’s best to work with the professionals.
They can draw up plans that abide by Building Regulations and hand them to your builder, making everyone’s lives easier. Make sure you choose a professional with the right credentials and a portfolio that includes projects that are similar to yours. For example, a chartered architect ensures work of a high standard.
Any extension built on your land must comply with Building Regulations. This includes a list of rules, from fire and insulation to drainage and access.
To make sure your plans are safe and secure, you will need to submit a Full Plan Submission or Building Notice to your council. Without it, you could face fines, legal disputes and your extension may be stopped.
You’ll need to make sure you can connect your extension to the vital networks in your home, including the electricity, central heating and plumbing systems (including water and sewers). For this, you’ll require detailed plans of your existing utilities and will need to hire professionals for the job.
If you are building on new ground, you will need to make sure there’s enough support to manage the weight of the structure. You should also check that the ground is not at risk of flooding or subsidence. A land surveyor can certify ground quality before you start planning.
Throughout the project, builders will need to bring materials from outside to the construction site. For this, you’ll need to make sure there’s a good pathway between the road and your site.
A good builder will advise on solutions, even if the only site access is through your home. You may also want to consider hiring a skip to store any waste and keep the site clean – your builder will be able to help getting a skip arranged.
Right to light
Always consider your neighbours when building an extension, especially when it comes to their ‘right to light’.
Every homeowner has the right to enjoy the natural light that passes over someone else’s land. So, if your extension project will cast a shadow over their property, you may not receive planning permission and will need to adjust your plans.
There is no set timeline when it comes to building an extension on a house. This is because many factors can delay your build, including:
Usually, the whole process can take anywhere between 6 and 15 months. This includes time for designing, planning and sourcing the right contractor.
For the build itself, smaller projects such as loft conversions and single storey extensions can take between 6 weeks to 4 months. For wrap around and double storey extensions, it can take more than 6 months. These timings are guidelines only, and as with all construction work, timelines can shift once the work begins.
If you’re considering extending your home, there are lots of options you can look at when funding an extension.
The best way to stay on top of the costs is to set a budget in advance. This should be realistic, accounting for factors such as design, professional fees and decorating the space afterwards.
Many contractors and builders work on a fixed budget contract. This can give you a clear picture of the overall costs and when payments are due.
A few ways you can keep the costs of your building extension down include: