18 Mar Building a House Extension guide

How to build a house extension guide.

We recommend following this guide for the best results.

Adding a new kitchen or a lounge extension to your house will give you more room inside and raise the home’s value considerably, as much as 25%. However, we at S & M Solutions Ltd think a reasonable-sized home extension, which does not leave you with a tiny garden, is an excellent idea; something evenly proportionates between the garden and house.

Since we get many inquiries about domestic projects such as Extensions and Lofts, we have made a list of items that will make it easier for you to achieve your dream extension. Nevertheless, for a home improvement, if you can’t do this task yourself, we have a pre-construction package, allowing us to prepare it for you for a set fee.

In no particular order, these items are what you need; however, additional documents may be required depending on your project’s location.

 1. Architectural drawings and planning permission – if required.

 2. Engineers structural calculations and specifications for structural steel and existing wall alterations.

 3. A pre-construction survey of the existing structure and underground services is critical because, more often than not, changes to the underground drainage are required for Thames Water and BCS to sign off your new shiny extension.

 4. Party wall agreement with your neighbours.

 5. The work schedule, including any additional work, is to be carried out. 

 6. Restrictions and design conditions are generally reserved for conservation areas or party wall agreements and can affect building costs. 

 7. Have an allowance of £2500-3500 per meter square for extensions overall, but that can vary on other additional works required with wiring, plumbing etc. It may also evolve whether a new kitchen is needed and other internal renovations go hand in hand with extensions.

-Updated prices as of November 2022 are now at £3500-4500 on average per metre square. A rise is mainly due to materials increasing by 28% in 18 months.

Now what I just mentioned above are the required documents, and, unfortunately, very few potential clients possess all the items mentioned above. Also, there is the other end of the scale with some drawings bought online; therefore, we recommend hiring a local architect.

Consider paying for your quote because, more likely than not, you will get an appropriately detailed quote for your extension. Many builders offer free estimates, but remember that’s all an estimate.

Estimates have a funny way of getting blown out of the water once the building work starts. That is because not one building is the same; every house has a different structure, but we’ll cover that topic in another blog.

Now you are ready to start looking for the right builder because not everyone is suitable to be your builder. Some companies are too big for your job, others are too small, and a few do not have the skill set to complete your extension and may abandon the project halfway.

Therefore, we recommend using a contract with your builder and FMB to have easy-to-understand contracts that are fair to both parties. Consider no more than three builders for the job; this action will help you get a clear picture of the cost.

Make sure the quote is specific to your project based on the architect’s design and structural calculations. That way, you are reasonably confident with your budgeting and can avoid unexpected bills later on, although it must be said that sometimes it can not be avoided.

Once you have a clear plan and have chosen your builder, it’s time to sit back and check if the work is going according to the schedule. Ensure to never change plans midway through the project to avoid delays and cost increases. Once the work is complete, you can enjoy the extra room and extra light flooding through the rear of the house. I would call that a success.

If pre-construction design and planning have been done correctly, the job will go as planned; however, as with any old house in London, surprises are not to be wholly discounted.

Check out this small video for a chance to see the different stages that the build goes through.

It’s best to consult a professional builder for advice and have the project completed quickly with no hassle. Consider contacting our experts here at S & M Solutions Ltd. We can help create the extension that you desire.