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In the new storage shed, I'd like to install a free standing loft.
Platform size will be about 14' x 16', designing for 40 lbs/sq ft live load, 10 dead. That adds up to a total of about 11,200 lbs gross design weight, or 350 pounds per foot of the 16' support beams.
A standard construction method for this, that has been recommended to me locally, is a steel C-beam along the long side, resting on vertical steel H-beams at each corner. Wooden joists to lay in the C-beam, preferrably bolted to welded ears.
However, I don't have an affordable source for this construction steel, and lacking the large welding/drilling equipment necessary to work with such thick steel, I can't do it myself.
So I'm wondering - is it feasible to make it all wood? Seems much easier to me. But... there are plenty of online calculators for wooden joists, just not for the beams and support poles.
Note that standard lumber sizes on this side of the pond seem to be a bit different from yours - I can get a wide range of depths in just under 3" width (70mm) as well.
To deal with possible concentrated (patch) loads on the 3/4" plywood floor, I'm spacing the joists 16 inches apart. According to common calculators, even a 2x10 joist would be fine for the 14 foot span at 16", so the common just-under-3"x10" size (70x245mm) would be overkill already - that's the joists sorted.
But can you help me size the 16' beams (that the joists will rest on) and the 8' tall corner support posts ?
The standard 40+10 lb/sqft load figures work out to 350lb per foot of the support beams, and just under 3,000 lbs vertical load per support pole.
I'll add braces for lateral loads, too. Thanks!!
Platform size will be about 14' x 16', designing for 40 lbs/sq ft live load, 10 dead. That adds up to a total of about 11,200 lbs gross design weight, or 350 pounds per foot of the 16' support beams.
A standard construction method for this, that has been recommended to me locally, is a steel C-beam along the long side, resting on vertical steel H-beams at each corner. Wooden joists to lay in the C-beam, preferrably bolted to welded ears.
However, I don't have an affordable source for this construction steel, and lacking the large welding/drilling equipment necessary to work with such thick steel, I can't do it myself.
So I'm wondering - is it feasible to make it all wood? Seems much easier to me. But... there are plenty of online calculators for wooden joists, just not for the beams and support poles.
Note that standard lumber sizes on this side of the pond seem to be a bit different from yours - I can get a wide range of depths in just under 3" width (70mm) as well.
To deal with possible concentrated (patch) loads on the 3/4" plywood floor, I'm spacing the joists 16 inches apart. According to common calculators, even a 2x10 joist would be fine for the 14 foot span at 16", so the common just-under-3"x10" size (70x245mm) would be overkill already - that's the joists sorted.
But can you help me size the 16' beams (that the joists will rest on) and the 8' tall corner support posts ?
The standard 40+10 lb/sqft load figures work out to 350lb per foot of the support beams, and just under 3,000 lbs vertical load per support pole.
I'll add braces for lateral loads, too. Thanks!!
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