The shed already has two coats of Weathershield Exterior undercoat. This no nonsense garden colour wood paint appears in the photo to be more of a stain than a paint. Will it just run off the undercoat?
Hello ACleeve,
We've spoken to the manufacturer and they have advised that they would not recommend it for this purpose.
"The undercoat is a “long life” product whereas the stain is a product with a relatively short life span. Undercoat is usually combined with a “long life” gloss (exterior) top coat, the stain however, can be used straight onto old or new timber with ample preparation.
The stain will partly penetrate into the timber giving it protection from the ambient weather conditions and also forms a breathable barrier against humidity whereby the raindrops are repelled and excessive moisture in the timber can vent out in the form of vapour. Undercoat “breathes” as well but certainly less than a stain…… applying stain on undercoat will limit the permeability of the substrate. Stain contains less binder (making it thus more breathable) than a paint and will therefore weather and last far shorter than a paint.
With this in mind, we can’t advise this will be a suitable combination. Although this may work in the interim, there is no guarantee of how long it will last for so would advise against the use of this stain with the undercoat."
Thank you for using Q&A (CW)
Answered by: Cwalm
Date published: 2020-12-14
