Gypsum-Fiber Roof Board - diaphragm capacity

[eng003]

Anyone have experience with gypsum-fiber roof boards like USG Securock? Can I use this product over cold-formed steel framing for structural diaphragm? Do you they design values and/or code acceptance?

 

[BAretired]

I have never used it, but check out the attached link.

BA

 

[MiketheEngineer]

Call the mfg??

 

[eng003]

what about using wood sheathing with steel cold form framing as diaphragm, where do I find design values for that? My client wants to use cold formed steel roof framing for small residential hip roof, don't know why...seems the benefits (light weight, less prone to moisture and insect damage,..?) would be outweighed by cost...any thoughts?

 

[MiketheEngineer]

IBC 2009??

 

[JAE]

I don't think gypsum boards can be, or usually are, used as diaphragms but would second the suggestion to contact a manufacturer.

However, technically speaking, unless there is an ICC report on it the building code may not find it acceptable and thus you'd have to convince the building inspector/authority that it is OK to use.

 

[MiketheEngineer]

Steel trusses and wood sheathing are used all the time. Contact Alpine Engineering or Mitek. They are two of the largest in this field. Once the plywood is on - you can put anything you want on top of it - assuming the additional loads are considered.

 

[focuseng]

1) Homasote: Firestall deck board

http://www.homasote.com/products/Firestall.aspx

2) Architectural products: Versaroc deck board

http://architecturalproducts.com/versaroc.html

The benefit in my experience is for fire ratings. Wood sheathing on steel framing is very acceptable structurally.

Make sure whatever you specify is rated as a Nailbase for your roofing materials (code approved). I don't think Fortocrete by USG is thus rated.

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MAP

 

[charliealphabravo]

You need the gypsum association publication binder.