new code understanding

[Peter Louis]

9.10.15.5. Construction of Exposing Building Face of Houses.......

.........

"b) the cladding shall
i) conform to Subsection 9.27.11.,
pg. 13
ii) be installed without furring members over gypsum sheathing at least 12.7 mm thick or over masonry,
iii) have a flame-spread rating not greater than 25 when tested in accordance with Sentence 3.1.12.1.(2), and
iv) not exceed 2 mm in thickness exclusive of fasteners, joints and local reinforcements, or......"

This is BC new code. Please help me understand "furring members"; "gypsum sheathing"; also iv.

Thank you

[Billy Stephens]

Construction Glossary (http://www.homebuildingmanual.com/Glossary.htm#A/C)

[Harry Janssen]

Furring members are a type of strapping,1x2,1x3,2x4, etc,gypsum,is drywall

[Peter Louis]

Thank you.

normally the clading is on osb or plywood sheathing. Why mentioned gypsum? could interior drywall be under the code requirement?

what is the meaning that " not exceed 2 mm in thickness exclusive of fasteners, joints and local reinforcements."

[Billy Stephens]

Thank you.

normally the clading is on osb or plywood sheathing. Why mentioned gypsum? could interior drywall be under the code requirement?

what is the meaning that " not exceed 2 mm in thickness exclusive of fasteners, joints and local reinforcements."

Gypsum is mentioned because it is fire retardant.

iii) have a flame-spread rating not greater than 25 when tested in accordance with Sentence 3.1.12.1

The cladding, ( exterior covering ) has a thickness of no more than 2mm thick. This 2mm thickness does not include the method to adhere it to the dwelling such as screws,nails or other hardware.

[John Kogel]

New gypsum products are out there. Exterior sheathing, yes.
http://www.dryvit.com/fileshare/doc/uk/description/duk614.pdf

Supposedly waterproof, and it doesn't burn. I haven't seen any yet. Maybe never will, but they've put it in the code book.

I'm not sure of the context for the 2 mm cladding statement. Not enough info. Could even be a typo.

Typo - error made while typing 1000's of pages of text. :D

[Billy Stephens]

I'm not sure of the context for the 2 mm cladding statement. Not enough info. Could even be a typo.
.
Yeah,
2cm sounds more correct.

[Peter Louis]

would plywood sheathing + vinyl siding fail under the code?

2mm clading: vinyl, metal panel?

[Markus Keller]

Around here the exterior grade drywall has had black paper on it all the way around. This has been around for a number of years now. Supposedly there is also a new version but I haven't had the need to look into it.
Mainly used to meet fire separation along the exterior when people are doing rehabs, additions or dormers in the City. A lot of our older properties only have 3' gangways in between the buildings. So doing anything to help with fire separation helps.
A lot of contractors have been using greenboard instead. The real scummy ones just use whiteboard. The black board cost more. Their theory is 'we are going to cover it up anyway'. Nice thought but it doesn't take reality into account.