Condensation from Day and Night Time Differentials

During the day, radiant heat warms the attic, which creates a large air molecule. That’s great because it soaks up the moisture from water use in the house as well as from the HVAC system (mechanicals in the attic).

At night, when the attic cools, the same air molecule becomes small and the moisture condensates on all surfaces. That condensation is absorbed by the structural materials and once the moisture content reaches 16% or greater, mold growth is supported.

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Ground Moisture

Moisture release from the ground, condensation from ductwork and plumbing, moisture intrusion/seepage through foundation walls and humidity that can exist outside the building envelope can exert a high moisture load on the crawl space. Efflorescence, the migration of minerals like calcium to the surface of concrete, is a visible conducive condition of wicking moisture from the positive side (exterior) to the negative side (interior) of a foundation wall.

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Your heating and cooling system won’t lose. When you set your thermostat, it will pump warm or cold air until it hits its set point. That seems great when it results in a comfortable living area, but if you have an inefficient attic, crawl space or basement where the duct work supplies this air to the registers, then year round, you could be pumping moisture into the unconditioned spaces in your home or business, resulting in increases in moisture content and potentially mold growth. Let an OnGuard Certified Moisture Control Inspector locate these inefficiencies so that you’re comfortable in your home, in your wallet and in your mind.

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Moisture from Foundation Wall Seepage

There are different types of basements. Daylight basements, sometimes called walkout basements, are very similar to crawl spaces where moisture from the interior (household water use, cooking, cleaning, and mechanicals) exerts a moisture load on the environment. Also, a temperature differential between the warm and cold side of the wall, wind-driven moisture into the exterior surfaces and/or building envelope, and in the case of unconditioned basements, poor ventilation, exerts a substantial and secondary moisture load on the basement.

In subterranean basements, sometimes called in-ground basements, the moisture load is primarily ground moisture. Moisture transmission from the ground impacts foundations walls, expansion joints and slab. The moisture load can be a combination of three types:

  1. Vapor transmission
  2. Wicking moisture
  3. Bulk moisture

As dew point and humidity increase in the basement, the moisture content of the structure itself increases. When moisture content reaches 16% or greater, mold formation is supported. Your OnGuard Certified Contractor understands how to inspect for each of these moisture loads and how to engineer a complete moisture control system for your basement.

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