Commercial Attic Ventilation Requirements

In cold climates the primary purpose of attic or roof ventilation is to maintain a cold roof temperature to control ice dams created by melting snow and to vent moisture that moves from the conditioned space to the attic ventilation acts to bypass the vapour barrier created by most roof.

Commercial attic ventilation requirements.

Throughout the balance of this digest the terms attic and roof will and can be used interchangeably. Attic ventilation is an important part of keeping your building healthy. 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. Intake vents located at the lowest part of the roof under the eaves allow cool.

The international codes i codes are the widely accepted comprehensive set of model codes used in the us and abroad to help ensure the engineering of safe sustainable affordable and resilient structures. Now we can calculate the ventilation requirements using these products and our example building from before. 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. Code requirements the international building code.

On the upcodes website. 2018 international residential code. The international code council icc is a non profit organization dedicated to developing model codes and standards used in the design build and compliance process. Shop directly from the manufacturer.

Current regulations state that the minimum attic ventilation requirements are 150 1. Chapter 8 roof ceiling construction. 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. The roofing industry also has practical guide lines for attic ventilation.

Proper attic ventilation can be an impor tant performance consideration when design ing and installing steep slope roof systems. On the upcodes website. Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents. Chapter 9 roof assemblies.

Roof vents exhaust or intake vents attic fans solar attic fans retrofit vents pvc vent caps ducted vents roof curbs and accessories. This means that if you have a 1500 sq attic then you would need at least 10 sf of ventilation. If we assume a ventilation strategy that involves a combination of dome roof vents and continuous soffit vents this building would need 22 15 diameter dome roof vents 3096 sq in. 21 5 and 387 lineal ft.

Typically building codes include minimum requirements applicable to attic ventilation. All aluminum rust free construction residential commercial and industrial sizes.