Attic Ventilation and Insulation

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Attic Ventilation and Insulation

How important is attic ventilation and insulation? Let me explain:
Let’s start with the ventilation:
·         In the summer, improper ventilation can cause attic heat to reach 160˚F. This can lead to cracking, warping & the breakdown of wood framing. Premature aging of your roofing system, such as curling of the roof shingles, damage to siding, exterior & interior paint and wallpaper. Believe it or not, a roof shingle warranty can be voided if it’s discovered you don’t have the proper ventilation.
·         In the wintertime, you can have warping of the wood frame, mold growth & buckling of shingles.
·         Industry standards say that for every 150 square feet of heated ceiling space, you need one square foot of ventilation between the soffit vents and either a ridge vent or box vents on the outtake. In the winter time, warm air will migrate to the attic. When it mixes with the cold plywood surfaces, it forms condensation. If the condensation sits on the plywood for too long, it will start to form mold growth on the plywood and supports. With the proper air flow in the attic, it will keep the plywood dry and free from moisture and mold growth. Remember; more ventilation is always better than not enough.  
·         Be sure your soffit vents are not blocked by your attic insulation. This will prevent proper air flow.
·         You may also want to check your bath fan venting. Is it run up and out of your roof or did the installer simply and improperly vent it directly into the attic? (This happens much too frequently.) If it is incorrect, call a mold remediator to not only rectify this but also to check your attic for possible mold growth.
Insulation and air sealing:
·         In most areas, code requires at least an R-50 insulation value. If you have less than that, consider upgrading your insulation. When you don’t have enough insulation, excessive heat loss in the winter can cause excessive amounts of condensation in the attic. Even the best air flow and ventilation will not dry the attic out in a timely fashion. Air gaps from plumbing, electrical wiring and recessed lights are a few of the problem areas for heat loss in attics. Make sure they are properly sealed off.

Preventative measures can save you time and money when it comes to how you insulate and vent your attic. It also will save you money by keeping your house cooler in the summer and warmer in the winter.  Also, be sure to take a look in yours to ensure all the proper steps have been taken and that there is no mold growth.

Visit Comprehensive Mold Management's website for more information at

1 comment

  1. Heard first time about Compmold. Its the most helping article I have ever read for attic maintenance so far. Heating and Cooling Kitchener