There is no denying how disheartening it is to see mold in your loft or attic and we recommend you to not succumbed by such infestation of spores. Inadequate and ineffective attic ventilation kick-starts the rotting process and this damage is not only stressful but it could also set you back many bucks in water-months each year.
The fact of the matter is that whilst rampart mold development is being removed, a plan with unparalleled foresight to obviate and prevent it by efficient attic ventilation must not be ignored. While being in Portland or peripheral cities in states of North West, you are braced with moist climate and houses are therefore susceptible for an aggravated as well as repetitive attic mold development.
So this read will guide you about the importance of roof top and attic ventilation and how it would affect over all life span of your roofing system.
Essentials of Roof & Attic Ventilation
You might have already observed vented roofs and attics having a ridge cap at the top crest of your roof as well as fans under the eaves. But our recommendation is that the roof ventilation designs based on Oregon state roofing code does not provide apt amount of ventilation and is the reason for number of mold cases.
Before going in-depth of our recommendations; let’s discuss reasons why roof and attic ventilation is important for a sustainable roofing system.
1. Reduced life of your roof
The enormous heat captured inside your attic because of poor ventilation would be transferred to inside of your house and also to shingles above your roof. Once the shingles are over heated their life span would be reduced and in-turn that of your roofing system.
2. Increased energy costs
From basics of ventilation and from stack effect we know that when hot air rises and get accumulated in the attic, it gets heated. As that hot air would not be able to find a way out; your roof’s temperature would be increased. You would require to use air conditioner and lower the temperature thereby increasing the energy costs.
3. Varying and uncomfortable temperature
In poorly ventilated house, if you go upstairs you would feel you have cold feet but the temperature inside of your attic would be 10 degrees more than that of the downstairs’. So this unequal distribution of internal temperatures never allows a balance and healthy environment in your house.
4. Damaged roofing frames
The wooden framing of your roof is inside your attic; and is therefore exposed for extreme climates. In hot months, the wooden support frames and braces would be damaged and warped out. This damage is accelerated in the absence of an effective and balanced attic ventilation.
5. Moisture infestation and aggravated Mold
Have you ever thought where would the steam of your shower would escape? All such damping factors would be accumulated in the attic. This steam would be condensed again which leads towards aggravation of mold. So your insulation would then be less effective because of such dampness and mildew.
Recommendations from Experts
The practical guidelines laid-out by experts of roofing industry recommends 50% of total free ventilation area at ridge as well as in areas at eaves and is stated as a balanced ventilation perfect for convection. In this regard, basic guidelines from U.S Department of Housing and Urban Development Statues should be followed.
The correct amount of roof ventilation is 1:150, i.e. from 150 square feet of attic area, one square foot area should be freely vented. The free vent area could be reduced in cases when the ventilation is balanced between eave and the ridge such that 40% at least and 50 % at maximum required free vent area is provided at the ridge or in situation when vapor retarder is included in the ceiling assembly.
It must also be considered that the ventilation openings must be protected from rain and snow infiltration. All the openings sized more than 1/8 inches should be screened and louvered.
In the end…
The bottom line of above discussion is that a balanced, effective and apt ventilation is an important design consideration for a hassle-free living. As prevention is better than cure, so even you have no other choice in case of mold to remove it, but if you would not streamline your roofing with the ventilation guidelines in national code you would be in trouble continually.