Shed fabrication. Rsj vs trusses.

[oilcooled :)]

im putting up a 47 ft by 25ft or possible 30ft shed this year. I’m going to put up a lean to roof instead of an A frame, with the vision that in time if I expand the workshop I can eventually turn the lean two roof back into an a frame. Is there any advantage of making trusses and what’s the best material two use or is making them a waste of time and a thing of the past?

 

[frank horton]

bit of a drawing would help.......always worry about long lengths of wood.........rsj are to heavy........have u thought about using Z purlins in the roof supports........strong cos of there shape, available in almost any reasonable length, heavy galv and plentyful......
easy to erect with 2 people........
a friend built a huge shed from Armco barrier (2 bolted together) for legs and Z purlins for the roof..........I bet if u get down the council roadway yard for a few quid u'll get enough for what ya need.........
mates shed has been up for about 10 years..........
just an idea..........Frank

 

[gaz1]

how about neither and build out of pallet racking

 

[oilcooled :)]

When I say trusses I mean steel ones I don’t believe in timber

 

[steve t]

trusses were built more when labour was cheaper, takes a lot longer to fab so from a commercial point of view sticking a couple of plates and a few cleats on a ipe is a no brainer, if doing it for yourself that's proberbly not so important, I wouldn't bother making a truss mind, even painting it is a pita

 

[frank horton]

HI gaz1,
like the idea but at what cost........never seen any large amounts of racking that'd be at an affordable price........
in my next works (the last 1 ever) will be using this racking to hold up the mezzanine floor.......2 birds 1 stone.......

 

[gaz1]

a little cheaper than you think unless you produce them

for a single row in the middle 2 side ones 9 high

https://www.ebay.co.uk/itm/Heavy-Duty-Warehouse-Pallet-Racking-Dexion-Uprights-900mm-Deep-6m-High/191990818029?_trkparms=aid=555019&algo=PL.BANDIT&ao=1&asc=20151005190705&meid=88573e1443c74d1398ef5b99a3a8921a&pid=100506&rk=1&rkt=1&&_trksid=p2045573.c100506.m3226

6m cut into 2

beams 2 lengths per rack support 2 to 3 shelves

https://www.ebay.co.uk/itm/Heavy-Du...890648?hash=item1c9a4e0cd8:g:l5IAAOSwySlaKGBR

oh and racking uprights looks like this

 

[gaz1]

 

[oilcooled :)]

I just imagine when you havea well engineered truss made out of maybe 2 inch channel or angle and loads of braces in it. There b less flex in it than a 7 or 8 inch rsj In a single sloped roof with no center supports.

trusses were built more when labour was cheaper, takes a lot longer to fab so from a commercial point of view sticking a couple of plates and a few cleats on a ipe is a no brainer, if doing it for yourself that's proberbly not so important, I wouldn't bother making a truss mind, even painting it is a pita

 

[8ob]

A guy up the road here has just put up a very wide ag building, he has used the beams below for trusses. I reckon he has spanned about 40`in one hit using these scaffold ladder beams, no sag whatsoever . Very light ,very rigid and cheap, got to love triangles

Bob

https://www.ebay.co.uk/itm/Scaffold...332507536327?_trksid=p2385738.m4383.l4275.c10

 

[Stingray]

I would use h-beam, I presume 47 ft is the length, so 3 bays of just under 16”,
Best advice I can give you is be careful when Welding end plates on as 1 degree out can equate to the post being 2 or 3 inches at ground level depending on post length, do not trust bandsaw angles, I used to check every cut and used a jig for end plates but this was for sheds with up-to 20 bays so for a small shed check with two bits of flat tacked together to make a tee at angle required if you know what I mean.
Another tip cut your end plates, mark first one carefully and pilot drill, use this as a template and clamp to other plates and mark holes on other plates with pilot drill, this does the same as centre punching, do the tops of your post as well with template, remember and drill two lots of holes on your high posts, this will save you drilling them later when you extend your shed, also put half cleats on end trusses as its handy to run something along the top of the beam to attach side sheets onto!

 

[oilcooled :)]

I went with the Warren truss design equilateral triangles. 60 by 60 by 6 main carriers and 50 by 50 by 6 inbetween. 7.5mtrs long and 400 mm deep with 1metre cleats braced back to truss to take pressure off timber purlins. Weight is 150kg, weight of 200 mm by 100 I beam would have been 200 kg if used and only half the depth so I presume this will be stiffer?