Conservatory Roof Options: Glass, Polycarbonate, Tiled Warm Roof Costs (2026)
The roof is the biggest thermal factor in any conservatory. Here is what each option delivers and what it costs.
Updated April 2026. Also covers roof replacement for existing conservatories.
Three Roof Types at a Glance
| Feature | Polycarbonate | Glass | Tiled warm roof |
|---|---|---|---|
| Cost per m2 | £300 - £600 | £500 - £900 | £900 - £1,800 |
| Typical 3x3 roof cost | Baseline (included) | +£1,500 - £2,500 | +£4,000 - £9,000 |
| Typical 5x4 roof cost | Baseline (included) | +£3,000 - £5,000 | +£8,000 - £15,000 |
| Roof U-value (W/m2K) | 2.8 | 1.0 - 1.4 | 0.15 - 0.18 |
| Noise in rain | Loud | Quiet | Silent (like a room) |
| Winter temperature (no heating) | 6-10 C | 10-14 C | 12-16 C |
| Light transmission | High | High | Low (no roof glass) |
| Planning (replacement) | PD (like-for-like) | PD | Check conservation areas |
Polycarbonate
Cheapest option
Advantages
+Lowest cost (included in most base prices)
+Lightest weight
+Diffuses harsh direct sunlight
Drawbacks
-Very poor thermal performance (U-value 2.8)
-Loud in rain and hail
-Yellows and becomes brittle over 10-15 years
-Significant overheating risk in summer
Verdict
Acceptable only if budget is the primary constraint. Budget-specify polycarbonate and plan to upgrade to glass or tiled within 5 years if year-round use matters.
Glass roof
Best all-rounder
Advantages
+Good light transmission
+Self-cleaning glass option (Pilkington Activ)
+Quiet in rain (laminated or safety glass)
+Solar-control coating reduces overheating
+Lasts 20-30 years
Drawbacks
-More expensive than polycarbonate
-Still significant thermal loss without solar-control coating
-Requires regular cleaning (self-clean helps)
Verdict
The recommended choice for most new-build conservatories. Specify self-cleaning solar-control glass on a south or west-facing roof. Budget the extra £1,500-£2,500 over polycarbonate - it makes a meaningful difference to comfort.
Tiled warm roof
Best performance
Advantages
+Excellent thermal performance (U-value 0.15)
+Silent - feels like a proper room
+Adds 20-30 minutes of fire resistance
+Plastered internal ceiling option
+AECOM data: saves ~£200/year in heating
Drawbacks
-Most expensive option
-Reduces light (no roof glazing unless velux added)
-Heavier - existing frames need assessment
-May require planning permission in some areas
Verdict
The right choice if year-round use is the goal. The £4,000-£15,000 cost uplift is justified by the dramatic improvement in comfort. Works particularly well combined with a lantern opening in the centre.
Tiled Warm Roof Systems Compared (Brand-Neutral)
Several manufacturers offer lightweight warm roof systems designed to replace existing conservatory roofs without structural alterations. Here is a summary of the main UK systems.
| System | Approx cost per m2 (installed) | U-value | Key feature |
|---|---|---|---|
| Guardian Warm Roof | £900 - £1,400 | 0.15 | Most widely distributed; many installers trained |
| Ultraroof 380 | £950 - £1,500 | 0.15 | Integrated Velux window option; good light penetration |
| SupaLite Tiled Roof | £900 - £1,350 | 0.15 | Lightweight; can be used on older frames without modification |
| Equinox Tiled Roof | £950 - £1,500 | 0.16 | Made-to-measure; good bespoke options |
Prices are installed costs including disposal of existing roof. Costs vary by complexity, access, and installer margin. Always get three quotes. Source: Homebuilding and Renovating, ConservatoryLand, supplier price lists 2026.
Replacing Your Existing Conservatory Roof
The UK has over 4 million existing conservatories, and a significant proportion have polycarbonate roofs that are 10-20 years old, yellowing, noisy, and thermally poor. Roof replacement is a growing market - and for many homeowners, it is a cheaper way to dramatically improve their conservatory than rebuilding from scratch.
The process: a specialist installer surveys the existing frame to confirm it can take the additional load of a tiled system. Modern lightweight warm roof systems are designed to be compatible with most post-2000 frames. Pre-2000 thin-section uPVC frames may require additional noggins or a perimeter steel beam to distribute load - this adds £500-£1,500 but rarely makes the project unviable.
Frame inspection
Free - £300
Most installers include this in the quote visit
3x3 poly to tiled
£4,000 - £9,000
Including disposal of old roof
5x4 poly to tiled
£8,000 - £15,000
Larger area, higher complexity