When trying to provide the best value to your client, do you guys typically stick with 3/8" thick glass for glass shelves (assume a width up to around 28", but usually less than 24")? Or do you get 1/4" thick?

Also, since tempering the glass makes it far stronger, do you prefer this? Does tempered 1/4" tend to bow if the clients load it up with china?

Assume the use here is china cabinets, so there's potential for them loading it up. Depending on whether they are more of a china aficionado, or just a freaking packrat.

It's cheaper to use laminated glass, but I don't think you can get it in 3/8". I would never use 1/4" in a 28" wide cabinet. Even if you have a 5th support in the back, 1/4" worries me. Personally, I never built one with just glass for the shelf. I do a wood frame with a glass insert. It certainly has a different look from the front, but it lets light pass through if the cabinet is top lit.

We mfg. store fixtures so a lot of glass shelves. Always tempered, polished edges. You might want to consult with a major supplier about load ratings. I did a Google and got a calculator from a glass supplier. Here is their result: 36" wide, 14" deep, 1/4" thick, Tempered gives a load rating of 70#s. (evenly distributed.) That's a lot of load! Did the same calculation but for annealed glass, 14#s!!
elitecustomglass.com/glass-weight-calculator/

We use tempered always though most suppliers say they use non tempered all the time in residential applications. I'm not comfortable not using tempered. We do 1/4" most always never a need for thicker.

There are a few online but Dulless has a calculator
https://www.dullesglassandmirror.com/glass-weight-load-calculator

If you punch in a 1/4 tempered shelf, 12 x 28 with supports at 2' (shelf pins at the ends) the calc states a 149lb load capacity. No shelf is going to have 149lbs on it.

I know you asked about thickness and tempering.
I like to temper for piece of mind, safety, never want a bizarre accident.
I like 3/8" for the look, has a more elegant feel.
I will use 1/4" if customer needs to cut cost and is ok with the look.

I use tempered and 1/4" is the norm for my cabinets. 3/8" is more for table tops that see heavier use.

Be careful about laminated as I'm not sure it would be stronger? 1/4" laminated glass is just 2 pieces of 1/8" glass with a layer of plastic between... I would think it would be weaker than solid 1/4" glass?

good luck,
JeffD

Laminated is pretty weak, will sag a lot. Not a good idea for shelves. If any of you use much glass, get set up with a wholesale supplier. Much cheaper than using a local. They all have route distribution and their trucks can drop at your shop on a regular basis. Occasionally you will get a decorator that will object to the tempered logo. The wholesalers can provide tempered W/O the logo but there will be a conflict with insurance requirements. Best to cover your a$$!

I'm not comfortable not using tempered. We do 1/4" most always never a need for thicker.