Moisture movement through all exterior walls is possible. There are many different types of moisture movement. Some are due to building defects allowing gross water entry. Others are the result of pressure and thermodynamic forces which push or pull moisture through the walls themselves, independent of the type of wall. In general, there are these types of moisture movement.
- Gross water entry
- Vapor pressure movement
- Capillary action
The slides in the slider to the right display some of these dynamics. Brick exterior walls, particularly at the basement level on a concrete slab, are always suspect for gross water entry at the floor level.
Water damage from foundation water intrusion
Note water staining and paper buckling
This is subtle but may indicate a large wall cavity problem with mold
A terrible mold situation between vinyl wallpaper and sheetrock backing
This is a large bathroom with a strong exhaust fan
The exhaust fan created a negative pressure environment
Moisture was sucked through the sheetrock from the exterior wall
Moisture could not pass vinyl wallpaper.
So water condensed between the two surfaces - hence mold growth
Another example of mold growth on back of vinyl wall paper
Moisture seeped between the seams and wet the sheetrock
This is a painted concrete foundation wall
Moisture moved through the concrete and wet the back of dried paint
Mold grew on the back of the paint and bled through to surface
Moisture movement can be seen as efflorescence behind paint
Note paint bubbling, scaling and flacking off
Removed insulation disclosed extensive mold growth on exterior wall
This is not an uncommon finding particularly in basements on slab
Rain water entered at the base and wicked up the paper
Obvious foundation moisture entry and paneling damage
To identify possible moisture intrusion around your home, carefully inspect the perimeter of your foundation from the outside. Look for areas where the earth ground looks to have settled next to the foundation. Landscaping by planting trees and bushes next to the house usually results in a loose and permeable soil. Overtime this loose soil will settle resulting in a downward (or negative) slope towards the house.This allows rain water runoff to saturate the soil next to the home hence the foundation.
Also, inspect the interior of your home. Look for signs of moisture movement particularly at the floor level.
Inspect entire exterior perimeter
Check the gutters and downspouts