On Thu, 18 Oct 2012 16:07:49 -0700 (PDT), wrote:

On Thursday, October 18, 2012 2:17:37 PM UTC+1, GMM wrote:
On Thursday, October 18, 2012 1:11:45 PM UTC+1, (unknown) wrote:
On Wednesday, October 17, 2012 9:07:08 PM UTC+1, GMM wrote:
On Wednesday, October 17, 2012 8:56:57 PM UTC+1, (unknown) wrote:

ultimately be loaded with all the junk you normally find in lofts - broken toys, old masters and all that.

On the other hand, I'm not sure it would feel too good to walk on an unsupported 14' span of 2 x 4
and if it deflects 6', then I would have to mount them higher than 2 x 8s so they didn't bang on the
top of the ceiling.

I regularly put my weight on a single 12' unconnected 2x4, and there's no visible deflection. it helps if you bring reality into this.

In a loft floor structure the joists are connected by the boarding, and sometimes noggings, both of which spread loads over multiple joists


I have been working from the BR tables as a) they would seem to give the best outcome and b) I
couldn't find anything else that gave useful information.

I shall take another look and see if I can find any useful info on this. Perhaps 2 x 6s would do the job
reasonably, although there is an attraction in 2 x 8s in that a future (currently completely off the radar)
loft conversion would be possible without having to take it all down and start again.

Timber requirements get ever deeper as the years roll by.


Probably the most compelling argument (for me) could be the fact that I have to lug them up 3 floors
to get them in, but that only needs to be done once.

Lots of victorian houses have 14' 2x4, 2x3 and even 1.5x3 loft joists, which all support a fully loaded loft without problem.

In my Victorian house I put a 4 foot fluorescent light up in my study (an ex-bedroom) and
was puzzled by why the second screw wouldn't reach through the L&P ceiling to the joist.
On standing back from light I realised the reason was that the ceiling had sagged and my
fluorescent was bridging an inverted hump. It's now fixed with longer screws and with the
centre touching the ceiling the ends are a good inch below the ceiling - so a deflection
of about 1"/2'.

--
Phil Addison