It is a standard measure of the water vapor permeability of a material. The higher the number, the more readily water vapor (in the gaseous state) can diffuse through the material. A perm rating of less than 0.1 is considered a Class I impermeable vapor retarder (which is also considered a vapor barrier); perm rating between 0.1 and 1 is considered a Class II semi-permeable vapor retarder; a perm rating between 1 and 10 is a Class III …
Mold in the home can be a health hazard if it’s allowed to grow and isn’t handled properly.
The type and severity of health effects depend upon:
- the level and duration of exposure
- sensitivity of the person
- the type of mold and toxin it may produce
- and other factors that can increase the health hazard (such as smoking).
People most likely to experience health problems from mold include:
- people with suppressed immune systems
- people with asthma or allergies
Mold in a home can be a serious problem, and one that deserves your immediate attention. Any problem with mold means there is a moisture problem. In addition to cleaning up the mold, you need to determine source of excess moisture solve the problem.
Building an energy efficient home or making energy saving home improvements should always be done with a good understanding of moisture and methods to control rain entry, humidity and hidden condensation. For more insight into moisture …
Glassfiber insulation is made from strands of glass fiber and temporarily loses its thermal resistance when it gets wet. However, if it can dry out and has not become compacted, it will retain its insulating properties.
Wet insulation in a closed wall cavity will usually not rapidly dry out. Wet insulation in a wall will migrate to the bottom soaking the wallboard and framing materials. Wetness (existing even just for a few days) will not only reduce the insulating quality …