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Recommendations for Subflooring

escyr | Posted in General Questions on

The second floor of our garage was built with “room-in-attic” trusses, where the center of the truss is open for a room.  The builder installed 23/32″ Advantech subflooring in the room area, and nothing in the area beyond the room.  I would like to use this area for storage and my question is, what should I use for subflooring?  Should I continue with the 23/32″ Advantech subflooring, use pine boards, plywood, etc?  I don’t foresee any of this area being used for anything other than storage as there is a diagonal truss member at every truss at 18-24″ spacing.

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  1. Expert Member
    Michael Maines | | #1

    Eric, the trusses were not designed to carry a "live load" (which includes storage) at the eave spaces, but were probably sized for a small dead load which would include insulation. There is a decent chance nothing bad will happen if you store stuff there, but just know that it could fail and nobody would be liable. Any material that will span from truss to truss and support the weight of what you want to store would be fine. Solid wood boards are usually stiffer and stronger than sheet goods, but 3/4" Advantech will span 24" with no trouble.

    1. escyr | | #2

      I appreciate the reply Michael. I wasn't aware that I shouldn't store stuff in that area.

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