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:
- kitchen/bathroom equipment
- external works such as drainage, paths and drives
- removal of any obstructions such as sheds and greenhouses.
It should be remembered that the extension building costs displayed are indicative only and quotations should be obtained from reputable contractors.