Bolting down a roof wall plate.

[SJSbuilding]

Hi All,

I have a project building a hall for my local Scouts. The internal cavity wall leaf will be paint grade blocks and rather than using the standard "holding down straps" every 2m on the inside face, which would be on show. I was thinking about other methods of construction. Could I bolt the 100x50mm plate down into the blockwork or use resin bolts vertically into the top course of blocks?
Holding down straps are 1000-1200mm long and cover over a number of block courses, so would the bolts need to as long?
Would it be easier to fit the straps on the cavity side of the inner leaf before the outer leaf is completed?
Any help or solutions.

 

[oldbutnotdead]

Those straps are specced to stop the roof lifting in high winds (by weighing it down with 4 courses of blocks). I don't think BCO would consider you were getting the same hold down force unless your anchors went through 4 courses (which would be madness).
You could fit the straps in the cavity but you'd need inspection before the inner skin went up (and/or pics), there might be corrosion concerns (damp outer skin, impossible to inspect in later years.
You could use stainless steel wire rope anchored to the foundations & rising through the cavity or on the outer skin but these are all novel solutions & would cost money in calcs and discussions. The usual restraint straps are cheap and not particularly ugly, once the wall is painted they'll vanish.

 

[^woody^]

Wouldn't this be the designer's job to correctly specify the work?

Anyway, the simpliest thing to do ( and possibly your only option) would be to fit the straps on the cavity side. Fixing to one course of blocks wont hold a roof down.

 

[Leofric]

The usual restraint straps are cheap and not particularly ugly, once the wall is painted they'll vanish.

Yes ,do them as bldg. regs in my opinion.