Window Replacement Calculator
Estimate the full cost of replacing windows in your home including frames, glazing, scaffolding and building control. UK prices for uPVC, timber, aluminium and composite windows.
Casement is the most common UK type
uPVC is most cost-effective
A-rated is the minimum for Part L
Total windows to replace
Supply and install per window
How We Calculate This
This calculator estimates the total cost of window replacement including supply, installation, scaffolding and building control fees.
The formula
Total = (Windows × Price each) + Scaffolding + Disposal + Building control
- Price varies by style, material and glazing type
- Scaffolding typically \u00A3800 if upper floors need access
- FENSA/CERTASS registration avoids separate building control fees
Frequently Asked Questions
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Last updated: March 2026
All calculations are estimates. Verify with your supplier.