Thinking of a home extension? We look at things to consider before starting a home extension with our tips on budgeting, planning permission, building regs, and selecting the right builder.
Set a Realistic Budget
Before starting your home extension, it’s important to set a realistic budget. Think about how much you can afford, and don’t forget to include extra costs for things like materials, labour, and planning fees.
It’s also a good idea to keep a 10%–15% buffer in case anything unexpected happens. You should get quotes from several builders or contractors to make sure you’re getting a fair price.
Remember, the cheapest option might not always be the best. Consider what’s included in each quote and make sure everything is clearly written down. A well-planned budget helps avoid stress later and keeps your project on track.
Check Planning Permission Rules
Not all home extensions need planning permission, but it’s important to check the rules before you begin. In many cases, small extensions fall under ‘permitted development’, which means you don’t need to apply for permission.
However, there are strict rules on size, height, and placement that must be followed. For example, you might be limited on how far you can extend from the rear wall of your property, especially if it’s a terraced or semi-detached house.
If your home is in a conservation area, or is a listed building, the rules can be much stricter. In those cases, planning permission is usually required, and you may also need special consents. It’s always wise to speak with your local council or planning department to understand what applies to your home.
You can apply for a Lawful Development Certificate to confirm that your plans don’t need planning permission.
This isn’t required, but it can offer peace of mind and help if you ever sell your property. Ignoring planning rules can lead to costly mistakes, including being told to undo the work.
Taking the time to understand planning permission helps avoid delays and keeps your project legal.
Understand Building Regulations
Even if you don’t need planning permission, your home extension must meet building regulations. These rules make sure the structure is safe, energy efficient, and fit to live in. Areas covered include foundations, walls, drainage, insulation, fire safety, and access.
You’ll need to tell your local building control team about your plans. They may inspect the work at different stages to make sure it meets the required standards. You can also choose to work with an approved inspector.
If you don’t follow building regulations, you might have to redo the work or pay a fine. You’ll also struggle to sell your home without a completion certificate. It’s best to plan ahead and make sure everything is done properly from the start.
Choose the Right Builder
Choosing a reliable builder is one of the most important steps when starting a home extension. A good builder can help bring your vision to life, while a poor one can cause delays, stress, and extra costs.
Start by asking for recommendations from friends, family, or neighbours who’ve had similar work done. You can also search online for local builders with good reviews. Always check that the builder is insured and has experience with the type of extension you’re planning.
Ask to see examples of their previous work and speak to past clients if possible. It’s also helpful to check if they are members of trade bodies like the Federation of Master Builders.
Get at least three detailed quotes. These should break down all costs and list what’s included in the job. Make sure the builder is clear about timings, payment stages, and who will manage the project.
Never pay everything up front. A payment schedule linked to stages of work is usually best. Also, make sure there’s a written contract before anything starts. This should outline the full scope of the work and protect both you and the builder.
Taking time to choose the right person helps your extension go smoothly and gives you peace of mind.
Get the Right Drawings and Plans
Good drawings and plans are key to a successful home extension. You’ll need clear designs that show exactly what you want to build. These are used to get planning permission (if needed), meet building regulations, and guide your builder.
You should work with an architect or a qualified designer to create accurate drawings. These should include floor plans, elevations, and technical details. Getting things right at this stage saves time and money later.
Your builder will also need these plans to give you a proper quote. Without them, there’s a higher risk of mistakes or misunderstandings.
Having the right drawings ensures everyone is on the same page and helps turn your ideas into a well-built extension.
We provide high-quality home extensions in Croydon. From single to double-storey extensions, we deliver reliable services that can enhance your home’s value, space, and overall appeal.
