Attic Ventilation Worksheet

Furthermore nrca also rec ommends the amount of ventila.

Attic ventilation worksheet.

Calculate or enter the square footage of the attic or area to be vented. Most building codes require a ratio of 1 150 ventilation space to attic floor space. Up to 6 12 7 12 to 10 12 11 12 and up. 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.

Gaf attic ventilation calculator. Calculations are based on 1 square foot of net free area for every 150 square feet of attic floor space. Use this calculator to help determine the proper amount of attic ventilation based on u s. Ridge vent must me installed per the manufactures instructions.

You can also contact your local municipality to check on building code in your area. 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. Attic ventilation calculator note. See attached required attic ventilation shall be provided for all reroof projects as determined from the attic ventilation worksheet.

One last thought attic ventilation is not there to get rid of heat it is there to get rid of excess moisture accumulating from the home. Jones has an attic space that measures 23 feet by 48 feet. 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. Let s look at the following example.

The ridge vent is installed on the peak with nails and shingled over for aesthetic purposes. Best ventilation is open soffit venting to a open vented ridge vent. 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. This yields a total area of 1 104 square feet.

Other options to meet your attic ventilation needs are. 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. Of attic space 1 150 ventilation ratio measured at the attic floor level ceiling. 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.

Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents. It can do both. Enter the width and length of your home including overhang in feet. Standard attic vents like af 50 s ventilation fans or solar powered attic fans.

Intake vents located at the lowest part of the roof under the eaves allow cool.