When is a good time to design & build an extension?

As home architects and specialists in the design and build of home extensions in London, we are frequently asked this question: When is a good time to design & build an extension? The answer is generally quite straight forward, but like everything in life there is no obvious yes or no, but rather pros and cons. In general, there is no bad time of year to begin the design and/or build of a home extension. We thought we would talk through the pros and cons of starting a home extension during the different seasons, as well as the associated timelines of the different types of extensions. 

Happy New Year! January 


It seems obvious to start at the beginning of the year and we can work our way through the months. January is probably the busiest time for both architects and builders. November and December typically distract homeowners and people put home modifications out of their minds to worry about post-Christmas and NY celebrations. Here at Home Tales, we see a spike in January which maintains through until Spring. It’s a great time to begin the design process. For the build, people tend to avoid having the builders in during the Christmas period as they are hosting or busy with the kid’s nativity or school holidays, so January start dates are extremely popular. If you want to start your build in January, we recommend having your builder lined up far in advance. Tell them you want a January start date and get your deposit down and your slot secured as soon as you can, because they tend to be the most in-demand slots of the year. 

Winter or Summer?

There seems to be a bit of general worry from homeowners about building in the winter months. If you are extending your property the house will be exposed to the elements for a period but whether it’s summer, winter, spring or autumn. The house should always be properly secured at the end of the day by the builder regardless of the time of year. Yes, it is true that rain can slow down the builder as certain elements of the build will need clear days to undertake work (ie. pouring concrete). It rains in England throughout all the seasons so choosing a particular season won’t make a huge difference in this regard. 

Some of our clients find the summer a good time to start because of school holidays. Many of our client’s time the build to align with a summer holiday or a long trip to the in-laws. The first four of weeks of a build tend to be the most disruptive as it involves the strip out and demolition. If you plan to live in it’s common for clients to vacate during this time and return when things are well into the build. A typical build for a side return extension will be 10-12 weeks to get the property watertight (doors and windows installed). For a loft conversion it will be a little bit less, more like 8-10 weeks.

November & Christmas 

As the festive season approaches, thing tend to slow down a bit as homeowners turn their attention towards the holidays. For planning permission, it’s worth recognising that local councils reduce their staff over Christmas and applications might be delayed. They shouldn’t be delayed much, and we often see 5-8 days in delays. In some cases, the planning teams can become very overwhelmed which might result in longer delays, but this is less common. Case officers can, if they chose to, offer us with an opportunity to amend a proposal if they find it to be unacceptable. They are not obligated to do so but do it to try and help you (as the homeowner / applicant) and to try to achieve a successful outcome on the application. Some might argue that with the increased workload over the Christmas period, they are less likely to give this goodwill as they are trying to clear applications and wrap up their case load before the holidays. 

When do I start then? 


For design, it’s never too early to begin the process. We offer unlimited amendments in our design phase, so you have a huge amount of time to experiment with different layouts and design options. It’s also not good to rush decisions so give yourself some time to absorb each option. Perhaps it would be helpful to come to a house tour during this time too! We offer house tours so you can see a completed project. This helps to visualise different spaces and to see design solutions that might work, or might not, work for you. Planning takes 8 weeks but do allow some extra time, if possible, just in case the council have delays. 

Get in touch with our team today on 0207 043 2378 or email us at hello@hometales.co.uk. You can book a free consultation via our live diary here. We look forward to discussing your project in more detail. 


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