Vent Sizes


I have mono trusses on either side of a firewall. I have the fire rating/wall material between them. Can I place a ridge vent above these two? Or should I use vents? How do I calculate the appropriate vent sizes and styles?


One thing to keep in mind with your situation: most fire wall assemblies need to extend up to the roofline (or in some cases beyond the roofline). As long as you do not affect the integrity of the fire wall assemblies or the trusses (i.e. cutting the trusses to insert a vent), this is not a truss design question. Fire concerns, vent sizes and ventilation are building designer/building code issues. Your local building code official would be better suited to discuss this vent usage with you.

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