How to keep a conservatory warm in winter

Why conservatories are cold in winter

Glass, especially single glazing and older double glazing without a modern coating, loses heat much faster than an insulated wall. A glass roof loses even more, because warm air rises straight to it. Add draughts around old doors and frames, and the room cools quickly as soon as the heating goes off.

Ways to keep a conservatory warm

Stop the draughts

Check seals around doors, opening windows and roof vents. Replacing worn seals and adding draught-proofing is cheap and often makes the biggest single difference.

Thermal blinds and curtains

Insulated blinds and heavy curtains, closed at dusk, slow heat loss through the glass at night. Roof blinds help most, because that's where the warm air goes.

Insulating window film

Insulating low-E film has a coating that reflects heat back into the room instead of letting it escape through the glass. It's most effective on single glazing and older units without a modern low-E coating, and it doesn't block the view. It won't match new high-performance glazing, but on the right glass it makes a noticeable difference to how warm the room feels.

Heating

A thermostatically controlled heater or a radiator on its own control keeps the room usable without heating it all day. Underfloor heating works well if the floor is being replaced anyway.

Floors and furnishings

Rugs on hard floors and soft furnishings make the room feel warmer and hold heat a little longer.

Replacement glazing or roof

New glazing or an insulated replacement roof makes the biggest difference of all, but it's also the most expensive and disruptive option, and a solid roof takes away much of the light.

Can one film help in summer and winter?

Some low-E films also give a degree of solar control, so they help a little in summer as well. If your conservatory is too hot in summer and too cold in winter, we'll look at which film, or combination, suits your glass.