Flashing Buying Guide
Selecting the right flashing to match your roof window can be one of the most difficult decisions to make if your knowledge of roofing or roofing materials is limited.
Our helpful and informative buying guide relieves you of all the stress of having to answer those tricky questions you don’t know the answers for. Such as; what material do I have on my roof and what type of installation do I want?
What materials do you have on your roof?
Tiles are produced from either concrete or clay and come in a range of shapes (profiles), sizes, and colours.
Roof window flashings are generally designed to work with most tiles on the market however manufacturers will have a couple of flashing options. Depending on the thickness of the tile, the bottom flashing apron will accommodate the change in height.
Slates come in two types: natural or man-made. They are predominantly grey in colour and come in a wide variety of different shades, textures, and patterns.
Slates are very thin in appearance and majority of the time they won’t be any bigger than 8mm thick. If you think you have slates on your roof and they're more than 8mm thick, it's very likely you will have a tile. If you live in Scotland you may even have a thick stone slab as your roofing material which would require a tile flashing.
So if you have anything generally grey and 8mm thick or less then this will more than likely be a slate and would require a slate flashing.
Plain tiles are most commonly found in the UK and have a traditional appearance. They are produced from either concrete or clay and are machine or hand made.
Plain tiles are similar in size and are approximately 266mm x 165mm - considerably smaller than interlocking tiles and slates. You would need 60 plain tiles to cover 1m² on the roof. The maximum thickness for a plain tile is 16mm.
The plain tile flashing kit is designed to fit with a plain tile so the finish is generally neater.
Whilst uncommon, it's not completely strange to have a pitched roof that doesn't consist of either tile, slate or plain tile. It's all down to preference and what the aspects of the build required at the time of construction. Some examples of this may be lead, zinc, single ply, felt shingles or standing seam.
If you sense your pitched roof has a material that is one of the those outlined above, you can contact our friendly team of experts who will help you determine what flashing you require.
What is the pitch of my roof?
Knowing the pitch of your roof is a key piece of information when choosing which flashing you need to go for. Some flashings will only work from a minimum pitch, such as 20°, but the recommended minimum pitch for installation of a roof window is 15°. If you’re looking to install a roof window below 15°, then please contact our friendly team of experts who will be more than happy to help.
There are a few simple ways to find out your roof pitch if you’re the homeowner. The easiest would be to download a roof pitch calculator mobile app from your phone provider’s shop. There are plenty of free apps that will help you detect your roof pitch.
The most accurate way would be to ask a roofer or builder to come and measure the pitch of your roof accurately. This can be done with an angle measuring tool or a ruler.
What type of installation are you after?
For a standard installation, roof windows fit on the batons on your roof and this means that some of the window will drop in between the rafters whilst the majority will sit above baton height. Depending on your roofing material, as much as 70mm may protrude above your finished roofing material.
Recessed flashings allow for a roof window to be installed deeper into the roof structure, meaning less of the window protrudes above the roofline and will generally provide a better thermal performing installation. By using different window brackets, the installation will slightly change.
A recessed installation can sometimes be a requirement if you live in a conservation area or have to comply with certain planning requirements.
Do you require a combination?
The manufacturing qualities of a roof window and its accessories have come a long way over the years. The possibility of creating your own combination of roof windows has become a lot easier.
Instead of choosing a big enough window to fit into the gap you have available, why not combine a number of smaller windows to create a unique combination?
By combining roof windows you have the ability to create something special and add real value to your home.
Each flashing piece is numbered and has its own set of instructions - it’s just like doing a jigsaw puzzle! The possibilities are endless and it’s only the size of the roof that can limit you.
If you are linking windows side by side then heights of the roof windows need to be the same, if you are linking one above the other then the widths need to be the same.
Please contact our experienced team with your enquiry.