Design loads for counter tops 1

[woody1235]

Sorry for this off-the wall- question, but need to know. I am a structural engineer in building design. However, I am asked from time to time to help architects design supports for counter tops. Not hardly main building structure, but asked anyway and I try to help.

I can't find a document or reference for what would be a good point load to use for counters. Don't find in code, and Google hasn't helped so far. I would expect that as much as 200 lb would be normal in case someone sits on it.

Anybody know what's typically done?

Thanks!

 

[BAretired]

These guys say their countertops are good for 100 psf, but that seems a little excessive to me.

http://www.concretenetwork.com/conc...n-ideas/posttensionedconcretecountertops.html

I have never designed a countertop, but maybe you should use residential loading, i.e. 40 psf plus an allowance for a roving concentrated load of about 400# spread over an area of 30" x 30".

BA

 

[CTSeng]

I've never been able to find good design criteria for furnishings which is probably why they break on occasion. I usually lean on the ADA 250lbs design requirement for shower seats and benchs when asked and would probably use the same for a countertop.

 

[vmirat]

I've designed many countertops, including computer work stations and restroom counters. I use 300 pounds concentrated load plus dead load and design each support to carry that, assuming there is no load transfer to other supports. That will take care of pretty much anything, including the maintenance guy standing on the counter to change a light bulb.

 

[woody1235]

Thanks to all for your responses.

I wound up using DL plus 3 - 200 lb point loads at equal spacing. The counter is about 16' long. I sized a tube to limit deflection to protect surface - has lots of reserve strength capacity.