Is it possible to paint Onduline sheets?

We do not particularly recommend any particular product or manufacturer. However the easiest material to use is external grade water based emulsion such as a Masonry Paint. One could also use a bituminous paint which in practice is harder to apply and maybe restrictive as to available colours. In any event and prior to commencing work, it is essential to totally remove any loose dust and debris from the sheeting. At the same time, it would also be advisable to test a small area to determine if there are any compatibility issues. This information is provided in good faith and there are no guarantees; the durability of the system will largely depend on the materials involved and the preparation beforehand.