What's the difference between a slab on grade and a monolithic foundation?

Ronaldo Johnitas
Updated: Aug. 27, 2020

I've been looking for a manufacturer of frost protected shallow foundation foam forms to get a quote for an addition in Michigan and keep reading about slab on grade and monolithic foundation styrofoam forms - is there a difference or are they the same thing? 

Responses (4)

Benoit Delorme
Benoit Delorme 4 years ago

Wrong answer Mike,slab on grade foundation form kit is only one pours !!and is structural slab that the  perimeter transfert load from edge to 12' inside (military technic and commercial technic from to many years.)

Mike Reynolds 4 years ago

Hi Benoit, thanks for sharing your thoughts. I'm afraid I don’t fully understand, but if you’re saying what I think you’re saying, I believe we are actually in agreement so let me give it a shot–

Yes, a slab on grade form kit can be done in one pour. If my comment that 'IF' it was an ‘insulated footing form’ then it may take two pours confused you, sorry about that. Ronaldo didn’t indicate which product they were considering, and I have seen form kits that are intended only for footings, in which case an interior slab would need to be poured afterwards, at an additional cost. Without knowing which product this person is considering, I wouldn’t want to mislead them to think all form kits are monolithic. Hope that clears it up for you Benoit, I'm pretty sure we're both fans of monolithic slabs!