Rear Extension:   by Phi  Architects

House improving extensions—18 affordable ideas

Amy Buxton Amy Buxton

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We understand if you're a little fed up of always seeing fantastical architect-designed extensions that must have cost a small fortune. There's nothing worse than seeing something you love, but knowing your home simply couldn't accommodate it, or that your budget can't stretch that far.

So, today we're looking at more modest, affordable home extensions. Frequently added to make room for a more functional kitchen or a bigger sitting area, these small but impactful designs won't break the bank but they will open your homes right up.

Let's take a look!

1. Full width, shallow extension

Single Storey Extension, Roxborough Rd II:  Houses by London Building Renovation
London Building Renovation

Single Storey Extension, Roxborough Rd II

London Building Renovation

Adding just enough room to make the inside feel exponentially bigger and the simple design won't cost a fortune.

2. Almost a conservatory

Essentially a conservatory, this dog-leg extension adds enough space for a dining room but doesn't require complicated, expensive construction methods.

3. Wooden option

Easy to erect and made from cheaper materials, this wooden home extension loses nothing for not being crafted more expensively.

4. Simple construction

Super simple in construction and modest in size, this extra room will have come in within budget thanks to the lack of full kit-out inside.

5. Small yet amazing

This innovative low-cost extension has added enough room for an offset yoga studio, which is exactly what the clients wanted!

6. Slightly larger option

Rear Extension:   by Phi  Architects
Phi  Architects

Rear Extension

Phi Architects

While the size of this extension might be a little bigger, the simple construction and low-cost materials make it such a bargain.

7. Micro extension

Primrose Hill, House Extension:   by Jeff Kahane + Associates
Jeff Kahane + Associates

Primrose Hill, House Extension

Jeff Kahane + Associates

When all you need is room for a seated area, you can embrace a micro extension like this one. They have a huge impact on your home but not your wallet!

8. Almost invisible

This extension is so modest it's almost camouflaged. A simple timber and steel design, this could almost have come as a flat-pack so it won't have cost the earth.

9. Classic brick

Rear Elevation:   by ABN7 Architects
ABN7 Architects

Rear Elevation

ABN7 Architects

A simple boxy brick design with timber framed windows makes this extension super cheap, simple to put up and perfect for the adjoining house.

10. Small but mighty

Extension to a Grade II Listed Building:   by WHITTAKER DESIGN

Extension to a Grade II Listed Building


Here's another smaller extension where, as you can see, the construction is simple but the extra space is invaluable. These modest additions are such great value for money!

11. Flat roof

Single Storey Extension Reginald Road - Northwood:  Windows  by London Building Renovation
London Building Renovation

Single Storey Extension Reginald Road—Northwood

London Building Renovation

Perfectly matched to the main house, this flat roof extension almost goes unnoticed. Without fancy glazing, it'll also be a steal!

12. Wood shingle

These single room extensions really work for us and we love this take, with wood shingles making it look more high-end.

13. Sloping roof rear porch

Refurbishment and Ground Floor Extension, Cockfosters:  Houses by RS Architects
RS Architects

Refurbishment and Ground Floor Extension, Cockfosters

RS Architects

When all you need is a slither of extra interior room, a small sloping roofed rear porch is ideal. Plus, it won't cost as much as a full-width project.

14. Magic box

Side extension build in timber frame:  Houses by Affleck Property Services
Affleck Property Services

Side extension build in timber frame

Affleck Property Services

If you've got a tiny bit of room you could be putting to better use, go for it! This ultra-simple, two-storey box build is small but highly effective.

15. Small and stylish

Dukes Avenue:   by Coupdeville

Dukes Avenue


This wooden box extension adds more than just extra space. It also raises the wow factor!

16. Rear terrace extension

Double storey extension for artist in Bishopston, Bristol:  Dining room by Dittrich Hudson Vasetti Architects
Dittrich Hudson Vasetti Architects

Double storey extension for artist in Bishopston, Bristol

Dittrich Hudson Vasetti Architects

Rear terrace extensions are usually very small as there isn't a lot of garden to sacrifice, but they sure are pretty and add good value to your home.

17. Twin win

Glazed side return extensions in Bath:  Conservatory by Style Within
Style Within

Glazed side return extensions in Bath

Style Within

There are actually two extensions here but they're so small and seamless you can't really tell! A great way to put that side-return space to better use, a small conservatory will have been fairly cheap.

18. Growing family

Fulham, London - rear extension, loft conversion and entire house renovation including inserting swimming pool:   by Zebra Property Group
Zebra Property Group

Fulham, London—rear extension, loft conversion and entire house renovation including inserting swimming pool

Zebra Property Group

Ignore the pool as we're looking at the small extension. The perfect way to create more room for a growing family, this rear addition looks a million bucks but won't have cost anywhere near it!

If you're keen to add extra space to your home on a budget, take a look at this Ideabook: Expand your home without forking out for an extension.

Why would you like to extend your home?
Whitton Drive:  Terrace house by GK Architects Ltd

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