I've got an idea for a big shelf. Good or bad?

[redpines]

My garage has a big laminated beam spanning 20 ft. It is 20 in deep (pic attached).

I'm thinking of hanging a 24 in wide shelf from the beam at the bottom edge. I've got a bunch of brackets that are 16 x 14 (second pic). These are heavy duty, 1/4 thick 1 1/4 wide steel, welded up by my brother. I would lag the brackets to the face of the beam with the 16 in length horizontal. Then suspend 3/4 in plywood by carriage bolts (with big washers) through the plywood to the bracket. Support the ends of the shelf with cleats on the walls.

I'd like to space the brackets at 32 in to allow 2 totes per space between brackets.

Because I have all the materials for this, it would be an easy way to gain 40 sq ft of shelving in currently wasted space.

So let me hear your opinions. Good idea or bad? Should I use more brackets? Is a 24 in shelf suspended from a 16 in bracket too much overhang? Is another several hundred pounds on the beam a problem?

Thanks.

 

[Zeke]

Go both sides of the beam with a full sheet. The weight will counter balance. Use the brackets as you describe.

Oh, I see you said 40 feet so you're already going to do both sides. Good.

 

[redpines]

Thanks for the suggestion.

The furnace & ductwork is in the way of a shelf on both sides of the beam.

The 40 sq ft of shelving I mentioned is one 2 x 20 shelf.

 

[j-guenth]

Go for IT! Sounds great!

 

[akdiesel]

Heavy duty brackets. Should support the weight fine with the way you want to do it except for the 32" spacing. Not sure how much weight you plan on each tote. 50 lbs seems to be a limit I would go for that span.
You have the parts needed but another option could be 7/8" Unistrut cut to 48' lengths, and span both sides of the beam for storage on both sides. Just lag it into the bottom of the beam by two lags on each strut. A 24" 14 gauge 7/8" strut can support 450 lbs evenly distributed.
This would allow for a clear space on top of the shelf.

 

[sberry]

I would put a tab on the bracket or couple small holes and use a couple 3 inch deck screws.

 

[redpines]

Not sure how much weight you plan on each tote. 50 lbs seems to be a limit I would go for that span.

Yeah, I know I would have to watch the weight. It's 10 ft off the floor, so it would be hard to get heavy totes up there. 30 lbs each seems reasonable.

So total weight (load & materials) on the beam might be 400- 500 lbs. Does that amount to anything for a 4"x20" microlam beam?

I would put a tab on the bracket or couple small holes and use a couple 3 inch deck screws.

Not sure what you mean... The plywood shelf would be hung under the brackets. Carriage bolts through holes in both with BIG washers on the underside.

The vertical leg of the brackets will be lagged (holes in bracket) through drywall into the beam.


Thanks for the dialog on this. I appreciate having a sounding board for my wacky ideas.

 

[Leaflessshadetree]

I'd bolt through the beam, large washers or plates on the back side. I'd also run at least a 2x4 under the shelf, bolt through the brackets, plywood and 2x4 again with large washers.

 

[sean Buick 76]

I agree with Leaf less shade tree.... I made a quick sketch of what I would do.... Use lag bolts in the beam, nuts and bolts with washers between the brackets, plywood and 2x4, and use lag bolts between the uprights plywood and 2x4. Pre drill the holes to eliminate cracking.

I just think that although those brackets are super strong it will be the limitation of the flex in the plywood with so much overhang. This is why I suggest uprights to support the front of the shelf (see pic below)

Keep in mind that the fasteners you use will be under severe stress, so use beefy fasteners.

I would use something like this to connect the uprights to the studs in the ceiling:

http://www.homedepot.ca/product/fence-bracket-2-inch-x-4-inch/935248

My sloppy quick sketch:

 

[stonesfan68]

I don't think that you're supposed to hang anything off of those beams. They are designed to carry the rated load and not much else.


Sent from my iPad using Tapatalk

 

[redpines]

Lots of good opinions here... I will consider finding a way to support the front edge of the shelf. The ceiling joists do not align so would have to get creative.

About more weight on the microlam - anybody with direct experience know if they are capable of more weight? And is drilling holes advised?

Thanks again.

 

[sberry]

This is why screwing to the beam may be preferable vs drilling for big bolts.

 

[sean Buick 76]

Another option to support the front of the shelf is a24" long 2x4 running right under the bracket... Sandwiching the bracket, plywood and 2x4 with nuts and bolts... Lag bolts are for sure the way to connect the brackets to the beam just be sure to pre drill or the beams will splinter.

 

[Zeke]

Putting a few pounds on that beam won't hurt. But lag or through bolting and storing engines and transmissions up there would not be wise.

 

[Bigplum]

Lots of info about , like this. http://www.anthonyforest.com/lslpg20-26.pdf

From what I can gather it seems a bad idea , unequal loadings and critical drill zones come up a lot . Might be best to find out the manufacturers and see what's safe

 

[redpines]

I occurred to me that I've been referring to the beam as Microllam (trademarked name for LVL) without really knowing if that's correct. Looking at some pictures now, and doing some research I would say the beam is actually PSL or LSL.

The first photo is one end of the beam I'm working with before drywall. The second is another smaller one used for the door header. Can anyone ID the material?

 

[jwhcars]

You could use cables to suspend/support the front of the shelf.

 

[redpines]

Anyone have experience with lagging into LVL, LSL, or PSL?

Researching this I don't get a lot of definitive info. I do see that some manufacturers recommend using lags to assemble beams.

 

[bczygan]

Your beam was designed and specified for a deflection limit that accommodates cladding with drywall, without the drywall cracking.

That means it is more than capable for the added loads you are proposing.

The absolute worst scenario I can imagine, is that it will be more susceptible to nail pops or cracks in the drywall.

Design the thickness of the plywood to accommodate the spans between supports and the cantilever you propose.

Remember that everything is a beam. Most times you are designing to limit deflection, not avoiding collapse.

Fastening is a balance between creating a monolithic structure, and weakening the components.

If you can use some threaded rod to catch the outboard end of the brackets and or shelves, you can eliminate the cantilever. Run them up into the attic and secure to a cross brace that transfers the load to 2 joists.

 

[redpines]

Thanks for the reassurances on the load, bczygan.

I follow everything you mentioned except this:

Design the thickness of the drywall to accommodate the spans between supports and the cantilever you propose.

Can you clarify?

 

[MadMechMaster]

I bet you can even eliminate the brackets. Run a rail across the bottom edge of the beam. This could be wood, but I would use angle iron. Attach the shelving to that with machine screws and nuts. Then suspend the front edge with cables or ready-rod.

Certainly box out the shelving material with stiffeners to increase the load. You can use cheaper 3/8 sheet then.

 

[sean Buick 76]

I think he means "make the plywood thick enough to span the supports".... Longer distance between supports means thicker plywood...

 

[vankaye]

Cable works great. I just did this with a buddy at his rented shop. Quick, easy and strong. The wire is stainless lock wire. Cable or chain would also work great. If you mount your 2x4 to the beam you won't need those big brackets at all.

Also, in your drawing both of your 2x4 should be turned 90* for strength. 2x4 laying on it side like that will sag with almost no weight on it.

 

[bczygan]

Thanks for the reassurances on the load, bczygan.

I follow everything you mentioned except this:



Can you clarify?

Of course, I was thinking of drywall when I meant plywood shelving material.