Understanding Attic Ventilation



Inadequate Attic Ventilation greatly shorten the life of your roof, cause havoc on your insulation,
And elevate the cost of heating and cooling your home!


It is estimated that 1 out of 3 homes in the United States do not have proper attic ventilation. Why? Because the majority of homeowners are unaware that attic ventilation can impact the life expectancy of their entire home!
Did you know that in the summer, improper ventilation can cause attic temperatures well over 150°F? This super-hot air gradually penetrates the ceiling insulation into your living quarters below.

Some of the things that result from an under ventilated attic are:


  • Premature aging of your roofing system (“crunchy” shingles)
     
  • Warping, cracking, or splitting of sub-framing
     
  • Damage to siding, exterior or interior paint finish, and sheet rock

  • Higher heating and cooling bill

A properly ventilated attic can help reduce the load on your air conditioner by transferring the super-hot air away from your attic before it causes damage. 
During the cold months, various household installations such as, bathtubs, showers, and cooking vapors can contribute to the build-up of excess moisture. Poorly ventilated attics will allow this added moisture to collect to the underside of the roof. Eventually condensing and dripping, soaking the ceiling attic insulation and reducing its efficiency.

Other damage can include:

  • Roof deck warping and rotting of the rafters 

  • Growth of mold and mildew
     
  • Buckling of shingles and roof underlayment
In northern climates attics should be properly ventilated to help prevent ice dams. In winter, ice and snow on a roof will melt and trickle down the deck to the cooler eaves. This run-off can re-freeze, creating an ice dam that may force water back up under the shingles and create a leak — causing hundreds or thousands of dollars of damage to your interior. Proper attic ventilation reduces the amount of initial melting that occurs on your roof, thereby reducing the chance that ice dams will form.

Adequate attic ventilation:
Adequate attic ventilation systems allow a constant flow of fresh air through the attic, maintaining the efficiency of the insulation and helping to lower temperatures in the living areas. It all comes down to a balance between air intake (at your eaves or soffits) and air exhaust (at or near your roof ridge). The FHA (Federal Housing Administration) recommends a at least 1 square foot of attic ventilation (both intake and exhaust) for every 300 square feet of attic space. For example, if your attic is 1,500 square feet, you need a total of 5 square feet of ventilation. This amount should be divided equally between intake and exhaust ventilation (i.e., 1 1/2 feet of each) to insure proper air flow through the attic.
Visit out website for more info and for specials on attic fans at http://www.avalanchecontractors.com

20211 Eden Pines
Spring, TX 77379
832-537-2317