If local code requires the 1 150 rule please double the requirements.
Attic ventilation calculator canada.
To find out how many vents you will need then round up to make sure you re getting enough ventilation.
If your roof is 1200 sq ft soffit floor space you will need 4 sq feet of roof ventilation.
Of ventilation for every 300 sq.
Here s how to determine your requirements.
There should also be a 50 50 balance of attic venting and roof venting.
Use this calculator to help determine the proper amount of attic ventilation based on u s.
The calculator will determine the number of square inches of net free area required for adequate attic ventilation based on the 1 300th general requirement.
Home attic vent calculator for years we have been working with architects and specifiers to ensure affordable roof ventilation that upholds building code standards.
Use the duraflo ventilation calculator to determine your home s ventilation requirements.
Divide your square footage by 300 sq.
For an uninsulated attic it s important to install a vapour barrier on the interior side of your roof before filling it with insulation.
Select ventilation product flex roll ridge vent multi roll multi purpose vent rigid roll ridge.
Width or area.
Gaf attic ventilation calculator.
Our passive roof vents are ul certified and rated to withstand wind pressure in excess of 200 mph.
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.
According to the national building code you need 1 sq.
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.
According to their requirements you should have 1 square foot of attic ventilation per 300 sq ft of attic floor space.
Vent calculator design your balanced ventilation system.
When installing your batts make sure to fit them tightly end to end as gaps in the insulation can greatly reduce your r value.
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.
Calculate or enter the square footage of the attic or area to be vented.
All lomanco attic ventilation product requirements are based on the minimum standard 1 300 rule as set forth by the international building code ibc and the international residential code irc.