Clad over conservatory roofs (and the damage they can do)
Being too hot in the summer and too cold in the winter is a perennial issue for owners of old or poorly insulated conservatories.
One way to improve this is to clad over your existing roof with a solid material. This may help to keep the heat in during the winter and the heat out during the summer.
The process involves adding a layer of cladding inside, outside or to replace the existing glazing. It can be a low cost way to make your conservatory more comfortable year round. However, if not carried out correctly, it can be a calamitous decision.
Read on to discover the potential pitfalls of clad over conservatory roofs.
Clad over options
Internal cladding
This is usually carried out by attaching battens to the inside of the conservatory roof bars. Plasterboard is then screwed into them, with insulating material in the gap between the glazing and the plasterboard.
External cladding
Wooden battens or ply boards are screwed directly into the outside of the glazing bars. This provides shading for the summer but generally doesn’t include any insulating material for winter warmth.
Internal + external cladding
This is a combination of the first two options. Plastic is often used inside, instead of plasterboard, because this type of cladding can increase condensation, which would spoil plasterboard. The original glazing may be retained or removed.
Solid panel cladding
With this option the panes of glazing are removed from the roof and replaced with solid panels. While this provides shading, it isn’t very thermally efficient, so it won’t help you to keep the room warm in the winter.
Things to consider
Structural integrity
The big issue with cladding is that your existing structure simply wasn’t designed to take this extra weight. This becomes a particular issue when wooden battens are used to support the cladding.
The original glazing bars, which everything has been attached to, could fail and result in a collapse. This could happen at any time, but is more likely when there are high winds and snowfall to add stress to your roof.
The bars will be further weakened if they have holes drilled in them to fix the cladding onto. This can also lead to water ingress within the bars and leaks into your conservatory.
This problem is compounded in the winter if your cladding does a good job of insulating your home. The extra thermal efficiency will mean that it takes longer for any snow on your conservatory roof to melt, resulting in greater weight loads, which the original bars were not designed for.
Solution
Ideally you should seek a full roof replacement (if the rest of the structure will allow this) rather than adding cladding onto a roof which wasn’t designed to hold it.
If you choose to go ahead with the cladding, ask your installer what the total weight of the roof will be once the cladding is added. Solid roofing systems are as light as 31kg/m2, so you should ensure that your roof + cladding come as close to that as possible.
You should also ask them what wind and snow loads the clad roof will be able to withstand. Make sure they give you specific figures and demonstrate how they were calculated, rather than just general reassurances.
Condensation
Where cladding increases the insulating properties of your roof, this can increase the risk of condensation. This can lead to leaks and, where you have installed a plasterboard covering, damp patches appearing.
Solution
Make sure your installer is including thermal breaks in the cladding structure. This will reduce the risk of condensation by creating a barrier between the cold outside and warm inside.
Fire safety
The cladding you install may be detrimental to the overall fire resistance of your roof.
Solution
Request a copy of the fire safety certificate to cover the entire roof (original roof + cladding) and ensure that it meets British Standard BS476-3.
Building regulations
Generally speaking, Planning Permission is not required to clad your conservatory or replace its roof, as it falls under “Permitted Development”. However, this may not be the case if you own a listed building or live in a conservation area or AONB.
However, Building Regulations approval may well be required. When you come to sell your home you will need to show Building Regulations approval for any changes made during the conveyance process.
Solution
Check that your installer has informed your local Building Control authority before the work starts. Make sure you receive (and keep safe) a copy of your Building Regulations Conformance Certificate.
Warranty
You should receive a warranty of at least 10 years for the new cladding. Keep in mind that this work is likely to invalidate any guarantee which you have for the existing conservatory structure.
Solution
Ask for written confirmation of the warranty for the new roof and a copy of your installer’s insurance (to ensure your warranty will still be valid if they go out of business).
If your guarantee for the original structure is still valid, check whether this work will invalidate it.
Window Wise solutions
We offer a range of roof replacement options, to give you the blend of light and thermal control you desire.
Our surveyor will advise whether your existing structure is suitable for a new roof. If we have any structural safety concerns we will not fit a new roof – we’d much rather disappoint you than create a safety hazard in your home.
If your existing structure is suitable, we can fit a range of roofs to perfectly suit your home and your needs:
- Fully glazed – if you’re thinking of switching to a solid roof to prevent extremes of temperature, our insulated, solar control glazing might make you think again.
- Partially glazed – these roofs provide the perfect balance between shade, thermal insulation and sunshine.
- Solid roof – the ultimate choice for thermal insulation and privacy.
- Flat roof – our flat roofs are leak-free and include the option of fabulous roof lanterns and skylights.
Find out more about our replacement roofs.
Visit our Haywards Heath showroom to experience our roofing products for yourself and chat to one of our design consultants, or contact us by phone or email.