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How Much Does A Kitchen Extension Cost?

This is usually the first question our customers ask. To help answer it, we've created a simple and cutting-edge extension cost calculator. Extension building costs can vary, especially in London. Hopefully, our cost calculator will provide some much-needed clarity.

Our tool makes it easy for you to see exactly what extensions are available to you, and what cost factors are included in your final quote. We've also provided 3D models of how your extension would look, bringing your new vision for your home to life.

House type

Select from below options
Detached
Detached
Semi-detached
Semi-detached
End of terrace
End of terrace
Terraced - Flat Back
Terraced - Flat Back
Terraced - L Shaped
Terraced - L Shaped
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All example costs:

All estimated costs for house extensions include building work, plumbing, electricity, glazing, external doors and applicable VAT

Flat Roof
Medium Smaller Rear Extension
Estimated Cost:
£70,000
Flat Roof
Medium Rear Extension
Estimated Cost:
£125,000
Crown Roof
Medium Rear Extension
Estimated Cost:
£95,000
Flat Roof
Large Wraparound Extension
Estimated Cost:
£190,000
Crown Roof
Large Wraparound Extension
Estimated Cost:
£170,000
Gable Roof
Large Wraparound Extension
Estimated Cost:
£108,000
Flat Roof
Large Wraparound Extension
Estimated Cost:
£112,000
Pitched (Hip) Roof
Large Wraparound Extension
Estimated Cost:
£95,000
Gable Roof
Medium Wraparound Extension
Estimated Cost:
£90,000
Flat Roof
Medium Wraparound Extension
Estimated Cost:
£93,000
Pitched (Hip) Roof
Medium Wraparound Extension
Estimated Cost:
£85,000
Gable Roof
Small Wraparound Extension
Estimated Cost:
£80,000
Flat Roof
Small Wraparound Extension
Estimated Cost:
£80,000
Pitched (Hip) Roof
Small Wraparound Extension
Estimated Cost:
£75,000
Pitched & Flat Roof
Large Side & Rear Extension
Estimated Cost:
£100,000
Pitched & Flat Roof
Medium Side & Rear Extension
Estimated Cost:
£85,000
Pitched & Flat Roof
Small Side & Rear Extension
Estimated Cost:
£78,000
Flat Roof
Large Side Return
Estimated Cost:
£80,000
Pitched Roof
Large Side Return
Estimated Cost:
£80,000
Flat Roof
Medium Side Return
Estimated Cost:
£68,000
Pitched Roof
Medium Side Extension
Estimated Cost:
£68,000
Flat Roof
Small Side Return
Estimated Cost:
£60,000
Pitched Roof
Small Side Return
Estimated Cost:
£60,000
Flat Roof
3m x 3m Rear Extension
Estimated Cost:
£60,000
Pitched Roof
3m Rear Extension
Estimated Cost:
£80,000
Gable Roof
3m Rear Extension
Estimated Cost:
£83,000
Flat Roof
3m Rear Extension
Estimated Cost:
£82,000
Crown Roof
3m Rear Extension
Estimated Cost:
£70,000

As one of London’s leading design and build companies, Plus Rooms has designed a comprehensive service to simplify the process of planning and constructing your extension. This includes obtaining building regulations approval, planning permission and permitted development rights. We can even set up temporary kitchen facilities allowing homeowners to remain living in the house throughout the build.

We cover many of the London boroughs and some of the home counties, please scroll down for recent examples of house extension projects in your area.

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