Side Extensions – What You Need to Know

Making the most of all the width that you have can be be great for both the inside and the outside of your house


Full article first published on Houzz
Hugo Tugman, Houzz Contributor

Where there is space to do so, extending your home to the side – rather than at the back – is a smart way to maximise your living area while retaining as much of your garden as possible. Be inspired by the many different ways to approach such an extension…

Take advantage of a gap

This late-Victorian, villa-style house is the last in a run of matching houses before a break in style. Before the two-storey side extension was added, there was a big gap between this house and the next one. Getting planning approval for the extension was nonetheless tricky, as the house is in a conservation area. Note the matching brickwork detailing and the way the extension is both set back and lower than the main part of the house. Planners tend to like such extensions to appear ‘subordinate’.

Be complementary

This example shows an extension to a house that has been built with a different roof form and is finished in a different colour. Even so, the extension does not look out of keeping in style from the main part of the house because it is complementary without actually matching. The simple flat-ish roof form would have been more cost-effective than extending the tiled roof across the full width.

Try contrasting styles

People are often very keen that extensions should ‘match’ the materials and style of the main house. However, a contrast both in style and material can work well. Here, a traditional stone house has been given a modern makeover with a contemporary glass and steel extension.

Twenty or thirty years ago, the attitude of planning authorities was that extensions should match, whereas planners now tend to be much more of the opinion that an extension should be ‘honest’, clearly expressing what is new and what was there before.

Talk to a design and build company that may be able to help with your side extension

Transform a side return

Many people with terrace houses will be aware of the possibility of a ‘side-return’ extension. But what is a ‘side return’ extension? Most traditional terrace houses have a front and rear main room and then what is known as an ‘out-rigger’ at the rear, often containing the kitchen, with space down the side of it. Extending into the space beside the ‘out-rigger’ is known as a side-return extension.

Transform a side return Idea 1: Keep light flowing

One of the main reasons why the Victorians and Edwardians followed the ‘out-rigger’ formula for terrace and, to a great extent, semi-detached houses, too, was that this allowed windows to be available to bring light and ventilation into the space in the middle of the house. Building an extension into the side return therefore runs the risk of creating the kind of dark spaces the original builders were trying to avoid, so employing significant amounts of glazing, particularly in the side-return roof, can enhance the daylight within.

Transform a side return Idea 2: Go for a modern twist

Just as with the larger house examples described above, the choice of matching or contrasting and classic or contemporary design is very much open.

Here, a very modern approach has been adopted with the bottom corner of the original brick wall having been cut away to create an asymmetrical composition. A deliberately thin line of construction denoting the new side wall and roof – to almost look like a simple folded panel – has been used with a great deal of glass to play the visual weight of the original against the lightweight nature of the addition.

Transform a side return Idea 3: Bring the outside in

One way in which the contemporary approach to a side-return extension can really enhance the internal spaces is by creating a minimal barrier between outside and in.

This example uses glazing with very fine framing at its edges, no intermediate glazing bars and a goal-post style surround for the doorway, so dining here will really feel alfresco and the daylight penetration into the house is about as uninterrupted as it can be.

Transform a side return Idea 4: Play with interesting forms…

There is no absolute right or wrong form for a side extension and very often the art of designing one of these is in looking at the particular nature of the house and how the light wants to be brought in.

This interesting example combines a flat and pitched roof, allowing a large triangular ‘window’ to be set part of the way back down the length of the extension for getting more light in and creating height inside. 

…or be really daring

Taking this idea even further, it is possible to use really dynamic and interesting architectural forms even on fairly small-scale extensions. This ‘reverse-pitched’ roof illustrates a technique that really opens up the feeling of embracing the external space, with the ceiling sloping up to the outside.

Ready to start your extension? 10 key things you might not know about planning permission

Embrace the width

Whether it is a side return or a side extension, the opportunity, if your house and plot allow, to make your home lovely and wide while leaving as much length in the garden as possible can really enhance your home. The sense of generosity given by that extra width of space and some wide glass doors out to the garden can be life-enhancing.


Come along to Grand Designs Live to get your project off the ground and book your free 30 minute consultation with one our experts in our Ask an Expert section to help you with your own extension.


Article provided by Houzz
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