Conservatory roof price calculator
Tell us the style and size of your conservatory. You will see an Eco Tech guide price for an insulated panel roof, how much heat the current roof leaks and what that leak costs a year.
Where the numbers come from
Your price depends on two things: roof area and roof style. We take the floor size you enter, add 12 percent for pitch and overhang, then apply our fitted rate for that shape. Lean-tos are the simplest. Every other shape carries more hips, cuts and trims, so each square metre costs a little more.
For heat loss we use the same formula an energy assessor would: U-value, multiplied by area, by heating degree days and by 24 hours. Choose a town and the sum switches to that town's own five year average. Without a town it uses the England figure of 2,150.
U-values used in the sums
| Roof type | U (W/m²K) | Loss from 12 m² on a 0°C night |
|---|---|---|
| 16 mm polycarbonate | 2.3 | 552 W |
| 25 mm polycarbonate | 1.6 | 384 W |
| 35 mm polycarbonate | 1.4 | 336 W |
| Glass, fitted before 2002 | 2.8 | 672 W |
| Glass, fitted since 2002 | 1.2 | 288 W |
| Eco Tech 75 mm panels | 0.43 | 103 W |
Think of a U-value as the watts lost per square metre for each degree of gap between indoor and outdoor air, so smaller numbers mean a warmer roof. Ours comes from a 75 mm solid foam core sandwiched between aluminium skins. Our guide to conservatory roof U-values goes deeper.
What to do with your figure
Happy with the guide price? Book a free survey. We measure the roof, look over the frame and bars, and give you a fixed price in writing. We order nothing until you agree. Ask for your free survey, or read our conservatory roof price guide first.
Calculator questions
How close is the guide price to my real quote?
It is built from the very size and style rates our surveyors use, so most written quotes fall inside it. Frame repairs, tricky access or extra roof lights can push it up. Your survey turns it into one fixed figure.
Why do you need the width and projection?
Both the cost and the heat loss depend on roof area. We take the floor area and add 12 percent for the roof pitch and the gutter overhang, which suits most conservatories.
What does heating degree days mean?
It sums up how much heating a place needs in a year: every day adds the degrees by which its mean temperature sits under 15.5°C. Our town figures average 2021 to 2025 using Open-Meteo weather records.
I never heat my conservatory. Does the saving still count?
The kWh figure assumes the room is kept comfortable. With no heating you will not see it on a bill, but the room stays several degrees nearer the rest of the house and becomes usable for many more months.
Turn it into a fixed price
We measure up, check the frame and give you a written quote. It is free and there is no obligation.