Floor solution for jacking loads

[2gins]

New garage built. The builders have been a nightmare from start to finish and have cocked up the floor. We wanted a reasonably smooth finish to put down an industrial 2 pack floor paint but they laid a 20mm ballast mix to 100mm depth and topped it with a thin levelling screed to get the smooth finish, against our instructions.
They didn't spike the levelling compound so it dried wrong so that'll be scraped out but what do we put down that'll withstand the point loads from a trolley jack?
What we asked for was a finer mix that could be powerfloated back to a smooth finish and we were happy to pay extra to get the right result but they promised a screed would be fine then fked it up.
Safe to say they'll have no interest in breaking out the whole floor and doing it right, and there are more important battles yet to fight. They've been an absolute shower and we just want them finished and gone after 18 months on a 9 month contract.

TLDR. Spec me a floor levelling system as thin as possible that'll take half a ton through a trolley jack without shattering.

[wolfracesonic]

I think getting in touch with someone like this, Ardex, is the best way forward; doesn’t sound like you’ve had the best luck with the project.

[OutInTheShed]

The surface layer will have more or less problems according to how it is supported by the substrate.

I would be thinking epoxy.

But a half ton point load will fk most things, depending on the pointy-ness of the point.

[kambites]

Epoxy is good, but the slab needs to be completely dry and free of contaminants or it won't adhere properly. Or you could just polish the surface of the slab?

ETA: Depending on how much jacking you'll actually be doing, another option is something sacrificial like those interlocking rubber tiles. They will eventually get chewed up by a jack, but when they do you can just lift the damaged tile and drop in a new one.

Edited by kambites on Thursday 26th March 21:58

[hidetheelephants]

2gins said:

TLDR. Spec me a floor levelling system as thin as possible that'll take half a ton through a trolley jack without shattering.

I doubt such a thing exists. Have the floor ground back until the screed is all removed, then paint it.

[PhilboSE]

I had a similar situation. Ended up having the floor ground back as level as possible, then had Dotti vitreous ceramic tiles laid on a bed of adhesive thick enough to take up the level variance.

Have since used a trolley jack on this floor on a variety of cars, up to a 2.3 ton Q7, without issues. I use the jack on a piece of sacrificial 18mm ply, just in case.

[NumBMW]

Level it off as best as possible and lay these https://www.ecotileflooring.com/product/e50010/