Moisture is one of the major enemies of home construction, and its potential problems aren’t limited to basements. Before you get too far along with your plans, inspect your home for evidence of moisture. Fix problems before you start remodeling.
Sleuthing in the Attic
Even if you don’t have an obvious leak, water can still come through the roof and cause rot. Inspect your attic on a bright day, armed with a screwdriver. Look closely at the sheathing for water stains. Poke suspect areas and look for matted insulation. Look also for pinholes of light shining through the roof. Poke around the edges of vents, chimneys, and skylight – sealing or flashing can often loosen. If you find trouble, you may be able to patch things up, but water damage often means you need a new roof.
Moisture in the Basement
Basement moisture can be caused by condensation, leaks, and hydrostatic pressure, which forces moisture up through the floor. Each problem has its own cure.
Condensation shows up on walls and cold water pipes in warm weather. To prevent these surfaces from collecting water from the moist summer air, insulate pipes and walls and cover wall insulation with a vapor barrier. Adding windows to increase ventilation will help. So will a dehumidifier, but don’t rely on it solely.
If your basement leaks, first make sure gutters and downspouts are installed and in good repair. Many problems can also be solved by grading the soil around the house away from the foundation. If these remedies don’t work, you may have to invest in an exterior or interior drainage system.
White deposits on the slab means you might have a moisture problem. To check for moisture, tape 2×2-foot squares of clear plastic to the floor every 2 feet. Lift them after a couple of days. Water droplets under the plastic mean moisture is wicking up through the floor from the soil, and you may need to consult with an engineer for solutions.
Persistent leaking, puddles, or flooding need immediate attention. Waterproofing the interior walls and sealing the cracks with hydraulic cement will sometimes cure these problems. Better yet, waterproof the exterior walls, and install a sump pump and drain lines that run to a dry wall.