Plastic cladding is used widely on exteriors (though it’s also used internally, for example on bathroom walls.) It is cheaper and easier to fit than tiles or metal cladding, while having the advantage of being just as resilient.
If you are replacing cladding, you may be able to use the existing sub frame if water damage hasn’t occurred, as plastic cladding is fixed to the wall in the same way as tiles and metal, i.e. via battens. It should never be attached direct to the wall itself. If you have to make a frame, use treated softwood battens at 400 mm intervals, screwing them firmly to the wall with sunken-head screws.
When it comes to windows, doors etc fix the battens so they’re positioned a little way back from the opening – about 1 ½ inches. This is to allow room for the edge trims that will cover the edges of the plastic wall cladding, to give a tidy finish. If the cladding is being placed over a single-skin structure such as a shed, you can insulate the gap between the frame and the boards. However, the insulation material must be well packed to avoid condensation problems – you don’t want to trap pockets of air, as these can heat up. Builders fitting plastic cladding often incorporate trickle vents to ensure good air flow and avoid condensation build-up.
It’s worth noting that plastic cladding itself has insulating properties, as it has a hollow profile, formed from two plastic sheets with internal struts for strength and to maintain rigidity. We at Bliby Plastics have plastic cladding in 3 profiles, including wood-grain effect soffit boards.
