How to Keep Your Conservatory Warm in Winter

Why Conservatories Are So Cold in Winter

A standard polycarbonate conservatory roof has a U-value of around 1.8 W/m²K — meaning it loses heat almost as quickly as you can generate it. For context, a well-insulated house wall might have a U-value of 0.3 W/m²K or lower. Heat pours out through the roof constantly, and no combination of space heaters and radiators can compensate efficiently. You end up spending a fortune on heating a room that's still too cold to use.

Glass roofs improve on polycarbonate but still typically achieve only around 1.0–1.2 W/m²K in double-glazed form. Even the best triple-glazed glass roof won't come close to the performance of a properly insulated solid roof.

Quick Fixes: What Helps Temporarily

If you're looking for ways to make an existing conservatory more bearable this winter, these can help at the margins:

• Thermal blinds — honeycomb-style blinds trap a layer of air between the blind and the glazing, reducing heat loss slightly; effective for glass walls but have limited impact on the volume of heat lost through the roof
• Draft proofing — seal gaps around doors, between the conservatory and the main house wall, and around older door and window frames; often low-cost and worthwhile regardless
• Electric infrared heaters — these heat people and objects directly rather than trying to warm the air, making a cold conservatory bearable for short periods; running costs are high if used frequently
• Electric underfloor heating — more expensive to install but comfortable and efficient for smaller conservatories; still loses much of its output through the roof if it isn't insulated
• Heavy curtain between house and conservatory — prevents cold from the conservatory affecting the rest of the house, but doesn't make the conservatory itself usable

The Permanent Fix: Replacing the Roof

Only one intervention makes a truly lasting, dramatic difference to winter warmth: replacing the roof with a fully insulated tiled system. Our Eco Friendly roof achieves a U-value of 0.15 W/m²K — that's twelve times better than polycarbonate, and comparable to the insulated walls of a modern house.

• Far better thermal performance — heat generated by your existing radiators or underfloor heating stays in the room rather than disappearing through the ceiling
• No cold spots — multi-layer insulation eliminates thermal bridging, the cold patches that form around structural elements in poorly insulated roofs
• Meaningfully lower heating costs — because the room holds heat efficiently, a much smaller heat source is needed to maintain a comfortable temperature
• Your existing heating is suddenly sufficient — in most cases, you do not need to install any additional heating; the same radiator or underfloor heating that was struggling before becomes more than adequate

Does It Make a Noticeable Difference?

Customers consistently describe the transformation as remarkable. A conservatory that was genuinely unusable in winter — too cold to sit in without a coat — becomes a room you can use comfortably with minimal heating. The change is typically felt immediately, on the first cold day after installation.

What About Condensation?

Condensation is a common problem in cold conservatories — moisture in the warm air from the house hits the cold surface of polycarbonate panels and condenses, dripping onto furniture and floors. A tiled roof with a breathable moisture barrier eliminates this entirely: the surface temperature of the ceiling is no longer cold enough to trigger condensation, and the vapour barrier prevents moisture accumulation within the structure itself.

Will I Need New Radiators or Heating?

In the majority of cases, no. The existing heating in a conservatory — often a single electric radiator or an extension from the central heating system — is perfectly adequate once the roof is insulated. The room simply stops losing heat so rapidly. If your conservatory currently has no heating at all, a single modern electric panel heater is usually sufficient post-installation.

What Will It Cost?

A tiled roof replacement starts from £1,495 for a lean-to conservatory, with most homeowners paying between £2,500 and £6,000. The energy savings, extended usability, and increase in property value make this one of the better-returning home improvements available. See our full cost breakdown or request a free quote — we'll give you an accurate figure based on your specific conservatory the same day you contact us.