So, let’s say you’re thinking about adding an extension to your home. The first thing to do is get really clear on what you want. Is this going to be a new kitchen-diner, a bigger living room, an extra bedroom, maybe even a loft conversion? Think about how you’ll use the space and also what kind of budget you’re working with. It’s a good idea to leave a bit of wiggle room for unexpected costs — around 10–15% extra is a safe buffer.
Once you know what you want, it’s time to check if it’s actually doable. This means looking into any restrictions on your property. For example, if your house is listed, in a conservation area, or has previous planning conditions, it might limit what you can do. You’ll also want to see if your plans fall under what’s called Permitted Development — which means you might not need formal planning permission — or whether you’ll need to go through the full planning process. At this point, it’s worth bringing in a professional — that is where we come in. We’ll visit your home, talk through your ideas, and help shape them into something that not only looks good, but also complies with planning rules and building regulations. We’ll produce some initial sketches and then develop them into proper plans.
If you do need planning permission, we will handle the application and submit all the necessary drawings and documents to your local council. The process usually takes a couple of weeks from our side, and about eight weeks of council time, during which neighbours can comment or object, and the council might ask for small tweaks. Even if your project is covered by Permitted Development, it’s still smart to apply for a Lawful Development Certificate — that way, you’ve got official proof it’s allowed.
Once you know what you are planning, and if it involves structural work, you will need to appoint a structural engineer to calculate and design the structure — foundations, beams and so on — that will support the building. The engineer’s information will be used as part of the pricing documents, and will also be submitted to Building Control in the next step for their input.
Next up is Building Regulations. This is different from planning — it’s all about safety, structure, insulation, ventilation, and so on. You can either submit detailed plans in advance (which get checked and approved), or go the faster route with a Building Notice, which skips the pre-checks but carries a bit more risk. A Building Control officer will inspect the work as it goes along, as requested by the builder.
Now, if your extension affects a shared wall or is close to a neighbour’s boundary — which is often the case in terraced or semi-detached houses — you’ll need to follow the Party Wall Act. That involves notifying your neighbours and possibly getting a Party Wall Agreement in place, usually by means of a templated friendly letter. If you don’t particularly get along with the neighbours, or your situation is trickier than most, we will progress this with the help of a Party Wall surveyor.
Once you’ve got all the approvals, it’s time to find a builder. This is a big decision, so take your time. Get a few quotes, check references, and make sure they’re insured and experienced with the type of work you’re doing. Ideally, you’ll have a written contract in place — something simple but clear, like a JCT Homeowner Contract, which outlines what they’ll do, when they’ll do it, and how much it will cost. We can help coordinate this for you, based on the drawings and schedules that we would have drawn up by this time.
Then comes the fun (and occasionally stressful) part — construction. The builder will get started on site, usually beginning with foundations and working their way up through the structural work, roof, windows, and finally the interior — things like electrics, plastering, and finishes. Throughout the build, your Building Control inspector will come out to check key stages.
Once everything’s done, you’ll get a final inspection. If everything’s up to scratch, you’ll be issued a Completion Certificate by Building Control. That’s an important document, especially if you ever plan to sell your home.
After the dust settles (literally), don’t forget to update your home insurance, and keep all the paperwork — planning approvals, certificates, drawings — somewhere safe. You might also need to let the council know about the extra space for council tax purposes, depending on how much your home’s value has changed.
