Suntuf Sunlite Twinwall Installation guide and tips
See the official installation guide for Suntuf Sunlite Twin wall here, or read on for a few other tips and tricks for planning and installing Suntuf Sunlite Twinwall Polycarbonate Sheeting.
Planning your structure
All roofing materials require some structure to secure the sheeting to. Suntuf Sunlite is no different.
The support structure for roofing purposes has it’s own terminology. Rafters run in the same direction as the sheeting, and purlins (battens) run perpendicular to these – see the image below. Sometimes the purlins will finish flush with the rafter so that the roofing sits directly on both. In other cases the purlins may sit on top of the rafters.
Suntuf Sunlite Twinwall can be installed onto supporting structures in two ways:
1. On top of purlins. When your structure has purlins, fixing screws are placed through the Sunlite Joiners and screwed into the Purlins to hold it in place.
2. On Rafters only. Normally there are no purlins in these designs. H-Bar Joiners will sit on top of the rafters giving a clean appearance. For this to be possible the rafters must be set apart to exactly the same distance as the joins in the sheet, which requires careful planning if you are building a new structure. If your structure is already built and the rafters are the wrong distance apart, you can either put in purlins or cut the sheets down to fit to the rafter centres. See the image below where the aluminium joiners are hidden by the rafters.
If you are building the structure make sure that you allow for a good fall or gradient. This is the slope on the roof that helps. the rain to run off into the gutter. The MINIMUM recommended fall for Suntuf Sunlite is 5 degrees. This is important for a few reasons:
1. It helps to keep your sheets clean (they will clean themselves with a good rainfall).
2. It helps with waterproofing – getting the water to flow where you want it to and not build up or go where it shouldn’t.
3. It stops water from collecting inside the sheet which can lead to dirty and mouldy sheets.
Selecting the right sheet
Once you have decided that a twinwall is the type of product that you are looking for, the next thing to do is select your colour.
Some colours will let more light or heat in, others will be darker and cooler. As a general rule, where you have light you will have heat – so sometimes you will need to compromise on what is more important to you.
Check out the table here to see the light and heat transmissions for each of the colours.
How it fits together
Sheets – The sheets are 10mm thick and 980mm wide, once they have been joined together with the aluminium Hbar and gasket they will be 1000mm (1m). Sheets are available from 1.5 meter to 9.0 m long
Hbar – Aluminium sections that are used to join the sheets together along the sides. They also provide a point where the sheets can be secured with screws. Under normal conditions you don’t screw into the the sheet – instead all fixings are secured through the aluminum sections.
Gasket – a rubber gasket is used between the sheeting and the HBar – this is for waterproofing and allowing the sheet to move within the aluminium framework during expansions and contraction.
Vented End Cap – Aluminium sections that are used to cap off the open ends of the sheets.
Lock Cap – used to hold the vented end cap into place.
Breathing and sealing tapes – used for protecting the ends of the sheets.
F Sections – Used to secure the edges of the sheets in most cases. The ‘tail’ of the F can point down if it runs along a rafter or point up if sealing the top end of the sheeting.
Other items include:
Two Piece aluminium H bars – a few things to consider here:
They are more fiddly to put together as they have a foam on the bottom and a wedge on the top to seal the sheets in place. Both of these have to be added to the H-bar prior to installation.
They are harder to install if you have a structure with a purlin design
Polycarbonate H Joiners and End Caps – a few things to consider: They don’t provide a good water seal and may leak. They are also not suitable for windy areas or roofing appliacations.
Installing the Sheeting
Read the complete installation guide here.
Finally, you will probably want to add some flashing to your area to weatherproof the sides of your new roof. See the pictures below to understand the flashing involved.