I'll be storing random boxes of parts to my hotrod project, gallon buckets of paint for the house, christmas ornament, rarely used tools, etc.Interesting, I'd like to hear what Daniel has to say about this.
What are you going to be putting on the shelf?
Is there any reason (clearance underneath) that you can't use a larger 2X in front?
I can't brace the underside since the garage door is under it. I could diagonal brace above. How would you atach the diag. 2x braces to the wall and shelf?First off, I am in no way an expert. So take this like you'd take helpful advice from some guy just walking past your garage.
Without a center support, I think that is going to sag. Just the weight of the shelving will eventually make it sag.
How to avoid this? You could do a diagonal brace below it, a diagonal brace up above it, or you could tie it into the roof with a vertical piece connecting to a ceiling piece that spans at least three of the ceiling joists.
Or you could use a 2x8 for the piece running the span. It depends on how much weight you're going to put on it.
My personal rule of thumb is to never have a 2x4 span more than 4' when it's being laid out up to 24" on center. (A 2x6 is good for 6', a 2x8 for 8', etc.) So by my reckoning, the ideal piece for that would be a 2x10. But that might be overkill if you're just storing Christmas decorations up there.
So you're saying I should get rid of the short studs and just run another 10'er down the middle attached to the 2' ledgers?It looks are you are trying to build a "park-under" shelf at the end of your garage.
Just add another 10' 2x4 to cut the span of the that intermediate 2x4 (that should be elimimated) because it is over-building for a 12" span between joists.
I have built several systems (usually 2 spand in a 24' or 30 wide garage with a post in the middle) in my homes through the years. Usually the rear 2x4 was anchored or attached to the rear wall. The only criticism I get is that they are "ungodly" strong and will attract people in a tornado warning. When I weighed 285#, I got up there and noted it no inkling of deflection. - If your are considering something like a 5.7 liter (350 ci) engine the concentrated weight might be a problem. If it is a 1000 hp Formula 1 engine, it is no problem.
Being supported on three sides, cutting the load on a 10' span by going to 12" spacing and eliminating the 2x4s from front to back makes a waorld of difference. - Fewer 2x4s, fewer hangers and much more rigidity and strength. Just edge nail the 3/4 plywood well, but think I used 1/2" plywood on the first couple.
They will be extended down the sides as well because I plan on extending the shelving down the sides. I just left them off my scetch for simplicity sake. Thanks!! What do you mean you would "span the 10' distance too?" Isn't that what my drawing does? I'm not quite sure I understand you.Might want to consider extending the side 2' 2x's out to 32" to catch the next stud
I'd span the 10' distance too
Assume 800,000 PSI for the modulus of elasticity [MOE] for the 2x4 as a worst case, I = 5.4 and y = 3.5/2 = 1.8".