On older houses attics may be ventilated only with louvered vents at the tops of gable ends walls although it s usually more effective to use these in conjunction with soffit vents.
Are all attics vented.
Effective attic ventilation systems reduce damaging heat and moisture in your attic promote energy efficiency by helping to reduce the load on your air conditioner in the summer and also reduce the risk of ice dam formation on your roof.
Unfortunately it s highly unlikely that the statements you hear will be true.
There are still some circumstances where having spray foam insulation in a vented attic on the floor might be the best option for your home.
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.
Each home is unique carrying challenges and structural requirements to match.
Too many people believe the importance of roof ventilation is to increase energy.
For decades designers of attics and crawl spaces have used cross ventilation to minimize the potential for moisture accumulation and condensation.
More than likely you currently have a vented attic because it s been the traditional way to insulate that space with cellulose or fiberglass for quite a long time.
The energy needed for air conditioning and heating typically goes up 10 when ducts are in the attic ueno 2003.
The choice of venting or not venting is a design and construction choice not a requirement determined by the physics or by the building code.
To get down to brass tacks the question becomes less about should you and more about how much you need.
Attic ventilation myths that are off the charts 1.
Hot air exhaust vents located at the peak of the roof allow hot air to escape.
More attic ventilation is good.
See the benefits of attic ventilation a new roof is more than just shingles.
Most homeowners and builders believe that attics should be vented.
Attics or roofs can be designed and constructed to be either vented or unvented in any hygro thermal zone map 1.
Vented attic it is exposed to extremes of hot and cold.
Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents.
The model building codes allow both vented and unvented roof assemblies.
However spurred by recent claims of energy savings and moisture control unvented attics have become popular in both residential and commercial applications.
Furthermore leaky ducts can lose as much as 20 of conditioned air flow to the attic bsc 2009.
The easy answer is yes your attic should absolutely be vented.
Just like properly sizing your furnace and air conditioning unit you want precisely.