Therefore it is not a watertight covering.
Vinyl siding chimney leak.
If an installer uses a material such as incorrectly this only exacerbates the problem.
Because of its design and application it provides a supplemental rain screen that enhances the water resistive barrier system by reducing the amount of water that reaches the underlying water resistive barrier.
Water leaks at soffit or eave overhang penetrations for chimneys that permits water to leak at the roof surface then pass behind the siding if the chimney is not properly flashed.
Vinyl siding is generally not recommended for exterior chimney siding because of the heat that the chimney produces.
Siding leak diagnosis and repair.
How to prevent water from flowing under vinyl siding.
Vinyl is a potentially leaky material and water trapped behind siding leads to decay and mold.
While stone and brick chimneys sit on a mortar bed wood vinyl sided and stucco chimneys are installed over a framed opening.
Vinyl siding is designed as an exterior cladding only and is supposed to be installed over other materials such as a weather resistant barrier.
Occasionally however it is found on chimneys installed on top of wood furring strips that provide a 1 inch clearance between the chimney and the siding.
Although vinyl is impervious to water when installed as directed by the manufacturer vinyl siding as a whole is not completely watertight.
Inspect the area above the leak including both indoors and out.
My photo above of ice below some courses of vinyl siding traces a moisture problem traced to improper installation of a through wall vent for a direct vent heating.
You can see that the very purpose of the chimney crown is to keep rain out.
The chimney crown is the cement part on top of the chimney.
Vinyl siding is designed to allow the material underneath it to breathe.
This article describes the causes of all types of leaks in building siding and wall coverings.
The bricks go up around the tile flue liners but at the top you need something to stop the rain and snow from just falling in around the tiles.
In this video this old house general contractor tom silva shows how to prevent water from leaking in behind vinyl siding.
Brick and stone chimneys if installed properly can last the better part of a lifetime.
Check to be sure weep holes are open along bottom of window openings.
