Laundromat Foundations

[Barry62]

I am an architect working on a typical shopping center type laundromat. The metal building company is to provide the foundation design but I wanted to be able to discuss it with the engineer.

I have read the threads over the years on foundations for oscillating equipment and was wondering if a series of floor mounted washers/dryers may fall into that category. Any insights from past projects?


Barry

 

[JoelTXCive]

I do not think the dynamic loading from a series of washers and dryers would pose a structural problem in the sense of a structural failure, BUT I do think vibrations could be what we call a 'servicability' issue.

You might get vibrations that are very annoying to the businesses immediately next door to the laundromat.

This is usually mitigated with dampening devices (possibly as simple as little rubber feet for the dryers) or isolation of the slab from the rest of the building.

I would also be interested in what others have to say. Definitely a good idea to bring up with the engineer when you meet with him/her.

 

[phamENG]

I have not done any laundomats, but I don't think it's something to be all that concerned about. While the motors will produce some vibrations, most of it will come from the impacts of the objects in the machines as they oscillate and spin. The chances of every machine being loaded the same, started at the exact same instant, and operate perfectly in sync are probably worse than winning the lottery, being struck by lightning, and bitten by a shark within a 5 second period. So your vibrations will be all over the place, and not build to a single, unified oscillation that could damage the structure.

That said, having a thicker than usual floor slab would probably be a benefit. Those machines, loaded with water (or wet clothes at the start of a dry cycle) are likely to be very heavy, and the heavier slab will help reduce those vibrations that do occur.

There are some other folks on here with more dynamic/vibration experience than I do - hopefully they'll chime in with some more insight.

 

[phamENG]

Good point, Joel - putting them on vibration mounts or at least a thick neoprene pad would go along way in cutting out nuisance vibrations.

 

[1503-44]

Are they 500 HP? Otherwise nothing more than just isolating the machines from the floor, if that.

Reality used to affect the way we thought. Now we somehow believe that what we think affects reality.

 

[wrxsti]

HEMI Washing machine and dryer

 

[JoshPlumSE]

Barry -

Good question. Generally speaking washing machines and dryers and such do NOT fall into the realm of dynamic equipment. The forces are just too low as are the frequencies.

I've designed foundations for this sort of thing for a skilled nursing facilities in California. Even OSHA didn't require us to consider dynamics. That being said, we did have to add a foundation pad in order to get proper anchorage because the slab on grade wasn't thick enough for the anchors we needed.

 

[Brad805]

If this is slab on grade then it seems unlikely to be much of an issue. We have put commercial washer/drier pairs on top of suspended floors, and then it can become an issue depending on the stiffness of the floor assembly.

 

[Barry62]

Thanks for your help everyone!
Barry

 

[Ron]

Not a structural issue but as Joel noted, it can be a noise/vibration transfer issue. I would specify an isolation joint in the slab for the area to prevent lateral transfer and use an acoustic sealant for the demising walls.

 

[1503-44]

Overkill. Handle it above the slab.
I don't like to make any holes in a slab that I don't absolutely have to, even then I prefer round ones.
IMO, that's just asking for cracks / propagations.

Reality used to affect the way we thought. Now we somehow believe that what we think affects reality.

 

[bridgebuster]

I'm with the others, seems like overkill. In the neighborhood where I grew up, the buildings on the commercial street were three story brick with masonry basement walls, wood floor system. The buildings with two laundromat's near my parents old house are still standing after 60+ years.