"Hugo Nebula" abuse@localhost wrote in message
news
[Default] On Sun, 30 May 2010 16:14:08 +0100, a certain chimpanzee,
"John" , randomly hit the keyboard and
wrote:

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?

From the photos, I would have a few observations:
1. The centres of the trusses looks very random. Either the centres of
the trusses either side are much less than 600mm, or the central pair
are way over.
2. Just looked it up, and provided that the hips are properly
constructed, and the distance between then is 1.8mm or less[*], you
don't need diagonal bracing (under the rafters from wallplate to
ridge) ...
3. Which you don't appear to have.

The bits of timber in question could be chevron bracing, but this is
only required to trusses exceeding 8m in length[*].

You could move the chevron brace to run in an opposite direction, but
I would be reluctant to remove it entirely without knowing for sure
whether it's needed or not.

The other question is, "do you really want your boiler in the loft?"

[*] Assuming normal wind loads (i.e., you're not on top of a hillside
or an exposed fen or something).
--
Hugo Nebula
"If no-one on the internet wants a piece of this,
just how far from the pack have I strayed"?


Many thanks.

The reason for planning to put the boiler in the loft is that I have very
little built in cupboard space. The existing floor standing boiler occupies
a substantial part of what could be a useful cupboard on the landing. To
replace it with a wall mounted boiler would still require a significant
amount of space being taken up - and the construction is only plasterboard
(no timber supports) - whilst I could overcome any weaknesses, it seems that
it may as well go in the loft - after all, it hardly needs to be accessed
frequently.

I have looked at the timbers again and have decided that if I bring my
proposed back board supports forward by 2" then I won't get a clash with the
brace which was my concern.

The large spacing incidentally is 650mm (centre to centre)