Stair cavity

[Rburt5]

I was crawling on my knees through my attic inspecting some wiring when my foot accidentally landed between two trusses, knocking down a piece of regular cardboard that was holding up the cellulose insulation over my stair cavity. Has anybody heard of such a thing? Is it normal to use cardboard over stair cavities? I attached a pic of the hole from above. Scared me to death when it fell through. I thought I was dropping with it! I guess I’m wondering if I should put more cardboard up there and throw insulation on top of it or if I should use something else to cover it.

 

[Bob Y.]

Hello,

I recommend that you use 3/4" plywood with 5/8" plasterboard on top for durability and fire resistance.

Bob

 

[Sponsor]

 

[Dana]

It's definitely not normal to use cardboard to sheathe any framing inside a house- it's a fire hazard! A fire in the stairwell would only take seconds to involve the attic.

Half inch sheet rock would be OK from a fire safety perspective, but still not great if there is a step-through possibility. If you take Bob's advice on the 3/4" plywood the 5/8" sheet rock wouldn't be necessary. Half inch gypsum would be enough.

 

[Rburt5]

Thanks for your help. I guess I know my next project.