UK cost calculator guide · Updated 29 Sep 2026
Triple Glazing Cost Calculator UK
A typical 1200×1200 white uPVC window moves from about £526 double glazed to about £615 triple glazed in the current national model. Use the calculator for your own size, layout and region rather than applying one flat percentage to every window.
Current fitted examples
These benchmarks use the same current pricing model as the main calculator. They are market estimates, not installer quotations.
How the triple glazing calculator works
The calculator starts with the product and window size, then applies the glazing upgrade to that specific frame system. That matters because triple-glazing premiums are not identical across uPVC, sash, aluminium and door products.
Region, job size and installation context are then applied to the fitted estimate.
When a simple percentage is misleading
A single “triple glazing costs X% more” rule can be too crude. Larger frames, different profile systems and heavier hardware can change the premium. Use the £89 example as a benchmark, not a universal surcharge.
- Choose the real frame type
- Use your actual or rough size
- Select your UK region
- Compare the final fitted range
What “fitted” means here: supply, standard replacement installation and ordinary 20% VAT are included. Unusual access, scaffolding, structural repairs, planning/listed-building requirements and highly bespoke work can sit outside the standard estimate.
Related price guides
Use these alongside the calculator to compare nearby specifications and project types.
Questions people ask
Direct answers to common cost-calculator searches.
How much does triple glazing cost for one window?
For the 1200×1200 white uPVC example used here, the current fitted centre is about £615 nationally.
How much more is triple glazing than double glazing?
For this example the modelled centre rises by about £89, roughly 17%, but the uplift varies by product and specification.
Does the calculator include fitting and VAT?
Yes. Standard replacement fitting and ordinary 20% VAT are included in the fitted estimate.
Calculate your own project.
Choose the product, rough or exact size, configuration, glazing and region. Your one-off personalised result costs £2.99.
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