On 30/05/10 19:34, Kipper at sea wrote:
On May 30, 4:24 pm, wrote:
wrote in message

...

In preparation for putting a boiler in my loft I am wondering if a
particular timber is just what the builders used temporarily to support
the roofing timbers whilst building the house. The house has what I
believe is called a double hipped roof.
The timber in question is about 3/4" x 3" - it runs at a shallow angle
from the bottom of a roof member - upward to tie in with 3 others.
Anyone able to advise? Do builders use temporary bits of wood to hold
things upright whilst assembling the roof?

Maybe this link will work and clarify what I am trying to explain:

http://tinyurl.com/2w5x8kl

The 3" x 3/4" or 75mm x 19mm timbers are there for a pacific reason.
They are not temporary supports; they are all part of the stress of
side movement on truss roof construction. It was found that in the
early days of truss roof use, that when the weight of the roof tiles
was loaded the trusses would sway. The diagonal braces, as they are
called. Were introduced to stop sway. If you’ve ever work on a truss
roof without bracing, as you moved about it was a bit unstable. They
are not put into position until all the trusses have been erected.

Interesting...

Any reason they didn't strap the rafters with diagonals?

In fact. I have seen under-rafter strapping on my old rented house
(modern truss roof) - so I'm *guessing* it was down to how the builders
felt on the day?

--
Tim Watts

Hung parliament? Rather have a hanged parliament.