Have an amount of 2.5" x 2.5" softwood timber aquired with new premises.
Building an internal shed for a couple of noisy machines, would like to use top of `shed ` as storage, take weigt of couple of people, not putting a dance floor up there ;-)
What sort of span can go to with 2.5" timber or would it be practical to glue/screw 2 together to make a 2.5 x 5 " beam?
That depends on the beam spacing and how the load is distributed. Also how much bending is going to be acceptable.
If you use 400mm centres, and a working on a design load of around 100kg / m^2 (which is a uniform load on the joist of about 0.8 kN/m), and you have them sharing the load, then you top limit would be about 1.6m.
(that's setting the limit based on the maximum permitted long term stress on the timbers in the building regs - not the permitted bending (which we probably care less about in this application). It also assumes they are made from something approaching C16 timber).
They would sag a bit at that load, but not spectacularly.
Yup, and that would make a substantial difference. That would get you to
Less than I thought..sometimes it`s better to ask first.
It ain`t B&Q banana wood thats for sure, there are some lenghts that are unplaned at 2.75, planed is exactly 2.5" square.
Quantity stacked outdoors where it has turned a fetching shade of sliver grey but dosent want to rot or warp. Was used as barge boards stacked in vertical I beams for big coal bunkers.
That sounds more useable, could I move to 600mm centres with doubled up joists and shorter span? 2.2- 2.5 probably about as deep as need to go.
Its an insurance issue if they fail at some point in future, but think may see a use as roof trussing in single level exterior sheds, need to reach some snow loading to hit failure.
I've been considering a similar problem for re-roofing an existing workshop. Flat roof with minimal fall covered in box section steel over an ancient felted timber structure now crumbling.
The timber rafters have sagged badly.
Like the OP I have some stored materials which could provide a cheap way out. In my case scantling cut Oak around 80mm square. I have in mind creating *pozi* joists by screwing lengths of WBP 12mm ply to the sides. Say 1m x 300mm with 300mm gaps for service runs.
The stumbling block is my lack of structural engineering knowledge:-(
The span required is around 5.5m and the spacing could be 1.5 or 3 or
4.5 or 6.0m:-) which would allow me to cut down standard 20' 0" steel Z purlins for fixing the new roof sheets. The only loading would be the BR snow load and the full span insulated roof sheets.
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.