Traditionally, conservatory roofs are constructed from polycarbonate, which is the cheapest option available, or they are glazed with glass. The modern upgrade to both is a solid tiled conservatory roof.
When discussing the thermal properties of a conservatory roof, the most important property is its U value which measures how effective a material is as an insulator. The lower a U value is, the more insulating it is.
Polycarbonate roofs are the least thermally efficient of the lot. Most old polycarbonate roofs will now be past their best and were never very thermally efficient to begin with. They let in too much sunlight and have a U Value of around 1.75. This means warm air escapes it easily, resulting in poor temperature regulation.
Modern glass roofs (of the double-glazed variety) are better because they have an air pocket trapped between two glass sheets. Glass by itself is not thermally efficient, but when doubled up it works quite well. The average U value of a glazed roof is 1.0. Glass roofs can also have reflective UV technology, which is either engineered into the glass or provided by way of a thin transparent sheet. This bounces some of the sun’s rays back, which helps keep the room cooler in summer, but it doesn’t cut glare.
Solid conservatory roofs which are tiled – to mimic the appearance of the main house – are even better. As an example, the Leka solid conservatory roof has a U Value of just 0.15, which is 168% more efficient than the average polycarbonate roof and 145% more efficient than the average glass roof. The result is a conservatory with outstanding temperature regulation – one that is cool in summer and warm in winter. Because the solid construction blocks the sun, a solid roof also eliminates glare.
Solid conservatory roofs reign supreme
For the highest possible thermal efficiency, solid roofs reign supreme. Glass roofs are improving all the time, but by design they cannot match a solid roof. The glazing allows too much heat to escape, and the fact the roof is transparent means sunlight will always warm it up – often to an uncomfortable point.
So a solid roof is what you want for efficiency. But there are additional benefits to a solid roof other than thermal efficiency. The biggest most obvious benefit is the elimination of glare, which is one of the chief reasons why homeowners don’t like their conservatory. If your conservatory is too bright to use comfortably, a solid roof will solve the issue. It also means you don’t have to rely on pesky blinds.
Of course, not all solid roofs are created equal. The Leka roof stands out because it is thermally efficient by design. It is engineered to provide a high level of thermal efficiency, and to be compatible with most existing builds.
The internal boards are insulated and then topped with PIR insulation sheets with a 15mm gap to create a warm air pocket. The insulation sheets are then topped with insulated outer sheets filled with XPS foam. Finally, engineered tiles which mimic slate or concrete are fitted to match the appearance of the roof on your house.
The result is a solid conservatory roof that is engineered to perfection and beautifully designed. Polycarbonate and glass roofs may be cheaper, but they are neither as efficient nor as stylish. If you want the best, go solid.
As you would expect, the price structure of conservatory roofs reflects the increase in thermal efficiency they provide. Polycarbonate > Glass > Solid is the order of things, and you really do pay for what you get in this industry.