A Guide To Extensions


Extension Beginner’s Guide


Extending is a popular way to add space without having to move. We explain everything you need to know from planning permission to costs, design work and much more


It is said that for every person who self builds there are 15 that add extensions to their homes. The reasons for all this are easy to see. It often makes more economic sense to stay put and avoids the need to find a plot. It means we can stay in the same neighbourhood if we like it and that the children can remain at the same school.


Why Should You Extend Your Home?

An overwhelming advantage of extending and not moving is the issue of stamp duty. It does not take a genius to work out that by the time you have calculated the agents fees for selling your house and the stamp duty on the one you are thinking of buying, you might well find you could build yourself quite a decent extension for the same price.


What do You Need to Consider Before Extending?

The trick is to extend and to come out well in the investment stakes, which means you have to put a lot of thought into even the smallest extension. For example, if you merely wish to extend the kitchen at the rear of your 1930s semi, should it be single storey or two? If it is the latter, what will go above it?


There are also practical issues to consider that are not directly concerned with the construction process. Access is a good example. If you add to your accommodation, will it mean more cars will need to be parked on the drive? If you have no drive then the lack of off-street parking might be a reason for the refusal of planning permission.


Similarly, if your house is in a terrace do you have rear access for the unloading of building materials or if not, will you have to bring everything from beams to blocks, and girders to guttering through the house?


Other important aspects to consider before you get to the stage of getting your plans drawn are matters like:


• soil conditions on the site;

• services;

• surrounding trees;

• any history of flooding;

• rights of way.


Another wise move is to get to know someone who has done a similar extension. They might have a builder or particular tradesman to recommend (or not recommend) but either way they will be full of useful tips on how long to allow for different tasks and many other matters.


How Much Does an Extension Cost?

There are many variables that will affect the cost of your extension such as soil type (which impacts the foundations); whether you are building a single or two storey extension; what the extension will be used for; and how much glazing you plan to specify.


Depending where you are in the UK, for a straightforward extension you should allow around £1,000–2,000/m². Remember that the standard of specification you choose will have an enormous influence on the build cost. Experienced renovator Michael Holmes, says a single storey extension will cost the following per/m².


• Basic quality £1,000 to £1,680

• Good quality £1,680 to £1,920

• Excellent quality £1,920 to £2,160