Extension Cost Calculator

House Extension Costs Calculator

The current uncertainty in the housing market has caused an upsurge in the number of house extensions being built. Adding a bedroom to a house is an almost certain way of increasing the value of a property beyond the cost of having the work done.

With the extension cost calculator you can get a quick, free, rough estimate of at least some of the costs involved in building extra room(s) for your house. By entering information about the extensions external size, roof type, number of storeys and the UK location, an estimate of the building cost can be found. The location of the build is needed, as costs do vary across the country and the price is weighted according to this information.

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Extension Diagram

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About the Extension Cost Calculator

The online extension calculator displayed above produces approximate costs of various sizes and types of extensions plus also weights it based upon the buildings location.

The data is based upon input from a quantity surveyor on real home extensions ranging in size from 2x3m to 4x6m. Extensions outside of these sizes are likely to be less accurate.

These extension costs exclude:

It should be remembered that the extension building costs displayed are indicative only and quotations should be obtained from reputable contractors - Disclaimer.