Water Behind Vinyl Siding

When siding is put back behind the gutter the lowest piece of flashing running down the pitch of the roof above must be fashioned to divert water into the gutter not behind the siding.

Water behind vinyl siding.

The most common causes of water damage behind vinyl siding include the following. Vinyl siding is designed as an exterior cladding only and is supposed to be installed over other materials such as a weather resistant barrier. If an installer uses a material such as incorrectly this only exacerbates the problem. Although vinyl is impervious to water when installed as directed by the manufacturer vinyl siding as a whole is not completely watertight.

How to prevent water from flowing under vinyl siding. In terms of siding this means layering sheeting flashing house wrap caulking siding and trim. Inspect the area above the leak including both indoors and out. How to waterproof osb behind vinyl siding.

Rainwater from missing or improperly placed gutters can end up behind siding. While a water resistant house wrap is typically installed under the siding it is punctured by nails during the installation process contributing to leaks. Vinyl is a potentially leaky material and water trapped behind siding leads to decay and mold. Water also enters the wall cavity through gaps at the edge of siding if it is not caulked.

In this video this old house general contractor tom silva shows how to prevent water from leaking in behind vinyl siding. Vinyl siding itself is waterproof and directs most water flow away from the exterior but even a small gap can allow water through. It is a misconception that vinyl siding doesn t need a water resistant barrier system. It s virtually impossible to completely seal any siding without additional materials.

Vinyl siding must be able to move independently of the wall surface.