Why Are Most Attics In Minnesota Vented

The starting point for any attic ventilation project is always what is the size of the attic space to be vented the international residential building code irc defines attic size in terms of its square footage length x width floor of the attic.

Why are most attics in minnesota vented.

In the summer natural air flow in a well vented attic moves super heated air out of the attic protecting roof shingles and removing moisture. Venting ventilation home insulation contractors minnesota. Generally speaking you need a ratio of 1 300 where for every 300 square feet of ceiling space you need 1 square foot of attic ventilation. In cold climates the primary purpose of attic or roof ventilation is to maintain a cold roof temperature to control ice dams created by melting snow and to vent moisture that moves from the conditioned space to the attic ventilation acts to bypass the vapour barrier created by most roof.

Why proper roof ventilation is important. Unfortunately it s highly unlikely that the statements you hear will be true. Throughout the balance of this digest the terms attic and roof will and can be used interchangeably. In other words the entire vent opening doesn t count as vented space.

Maybe you ve seen a fan in the side of your attic under the eaves or maybe you re aware of the ridge cap at the peak of your roof. Taking advantage of this natural process referred to as passive ventilation is the most common way to vent an attic. Many homes already have attic vents in place that can be used. Inadequate venting in your attic causes all sorts of problems from wood rot to mildew peeling exterior paint rusty nails screws roofing problems and even energy loss.

Once a contractor knows the attic square footage the amount of necessary attic ventilation. A properly vented attic is very important. If you walk down to your local lumberyard and lean on the counter the employees and nearby customers will offer a variety of opinions about why attics need to be vented. The insulation will resist heat transfer into the house.

How much ventilation does an attic need. That said air resistance and interference such as vent grates reduces the area of true ventilation. In order to facilitate this exchange of warm and cool air the general rule. You re probably aware that most attics and roofs are vented.

The most common mistake homeowners make when installing insulation is to block the flow of air at the eaves. Efficient especially if ductwork is in the attic rudd 2005. Roof vents and attic ventilation. Most homeowners and builders believe that attics should be vented.

If you have a high pitched roof the vented attic system may make the most economic sense since there is less area to spray the foam.