Attic Ventilation Worksheet

Federal housing authority recommends a minimum of at least 1 square foot of attic ventilation evenly split between intake and exhaust for every 300 square feet of attic floor space.

Attic ventilation worksheet. There should also be a 50 50 balance of attic venting and roof venting. Let owens corning roofing help you calculate exactly how much ventilation you will need for a healthy and balanced attic with our 4 step ventilation calculator. Utility penetrations knee walls and attic access openings dropped ceilings or chases adjacent to the thermal envelope. Up to 6 12 7 12 to 10 12 11 12 and up.

Proper attic ventilation consists of a balance between air intake at your eaves soffits or fascias and air exhaust at or near your roof ridge. If your roof is 1200 sq ft soffit floor space you will need 4 sq feet of roof ventilation. Tips for assessing your needs. Enter the width and length of your home including overhang in feet.

According to their requirements you should have 1 square foot of attic ventilation per 300 sq ft of attic floor space. Attic ventilation calculator thanks for your interest in our attic ventilation calculator. Calculate or enter the square footage of the attic or area to be vented. Proper attic ventilation consists of a balance between air intake at your eaves soffits or fascias and air exhaust at or near your roof ridge.

Save this simple excel file to your computer and use it any time. Select the roof pitch that is closest to yours. Calculations are based on 1 square foot of net free area for every 150 square feet of attic floor space. Attic ventilation calculator note.

Of attic space 1 150 ventilation ratio measured at the attic floor level ceiling. For large volume attics such as where roof slopes are greater than 8 12 designers also should consider increasing the amount of attic ventilation to account for the additional volume of attic space. Continuous whole house mechanical ventilation worksheet single family residence to facilitate permit issuance and energy code review in accordance with the 2015 michigan residential code please. Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents.

The attic ventilation worksheet shall be completed by the contractor applicant to determine the number of vents required to comply with minimum building code requirements. With this tool you can quickly and easily estimate your ventilation needs. Intake vents located at the lowest part of the roof under the eaves allow cool. See attached for large structures or structures with complex roof and attic areas a roof plan shall be provided showing location of existing and proposed attic vents.