Hairline cracks in rated partition walls 1

[darthsoilsguy2]

Curious how cracks in 1-hr rated walls are viewed by the industry. I'm not aware of language about having to repair a hairline crack in a rated wall. It would seem that an open crack with some measurable width to it (lets say 1/32" or greater) would need to get patched to maintain the wall rating. Thoughts on hairline cracks?

 

[cdafd]

I would say it has to be maintained/ repaired


From IFC


Section 704 Joints and Voids



704.1 Maintaining protection


Where required when the building was originally constructed, materials and systems used to protect joints and voids in the following locations shall be maintained. The materials and systems shall be securely attached to or bonded to the adjacent construction, without openings visible through the construction.

Joints in or between fire-resistance-rated walls, floors or floor/ceiling assemblies and roof or roof/ceiling assemblies.
Joints in smoke barriers.
Voids at the intersection of a horizontal floor assembly and an exterior curtain wall.
Voids at the intersection of a horizontal smoke barrier and an exterior curtain wall.
Voids at the intersection of a nonfire-resistance-rated floor assembly and an exterior curtain wall.
Voids at the intersection of a vertical fire barrier and an exterior curtain wall.
Voids at the intersection of a vertical fire barrier and a nonfire-resistance-rated roof assembly.

Unprotected joints and voids do not need to be protected where such joints and voids were not required to be protected when the building was originally constructed.

 

[stookeyfpe]

We can't answer your question without additional information. Is the wall an assembly of gypsum wallboard, concrete masonry units, bricks, or cast in place concrete? Secondly, is the wall required to have a minimum fire-resistance rating?

 

[chicopee]

a one hour fire rated partition is non-bearing and would be used where there are no issues of Life Safety, storage of hazardous materialand equipment such as boilers. UL has details and diagrams of fire rated fire walls and partitions so check UL for possible repair methods. Thirty years ago I had these UL pamphlets but there were no details about repair methods but now UL may have expanded on repair methods. Back then these pamphlets were very expensive, so don't expect them to be cheaper.

 

[darthsoilsguy2]

wall is 1-hr rated sheetrock wall separating occupancies. it wasn't so much a question about how to repair a sheet rock wall, but whether hairline cracks are required to be patched for rating maintenance.

 

[cdafd]

Was it tested by UL with cracks??

Would it pass the UL test with cracks.

Yes they need to be fixed

 

[stookeyfpe]

US Gypsum has an excellent design document that addresses gypsum board construction practices. They also have extensive guidelines for problems and remedies. I would use this as a criteria for evaluating the fire-resistant rated wall assembly.

https://www.usg.com/content/dam/USG...s-remedies-and-preventive-measures-can-en.pdf