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Repair Basement Concrete Support?

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Dec 05, 2013, 10:30 AM
Repair Basement Concrete Support?
Hi. My basement is unfinished, with a concrete floor. There is a block of concrete 6'w x 6'd x 2'h, cemented to the floor. The furnace/AC/blower is resting on the block.

Through what I think is age and constant vibration, the block has become cracked. The cracking has gotten worse over the past few months.

I think I should build a wooden scaffolding around the cement pad (cover the wood with a disposable plastic tarp), and pour new cement in/on the cracks and let it set to re-strengthen the block.

Since I have no idea if that will actually work, I am here. Smile

Can anyone add comments and ideas? I need to address this before the slab comes apart.


This message has been edited. Last edited by: CoughCough,

Cracked support concrete pad

Dec 05, 2013, 11:32 AM
cute. does that crack extend through the concrete pad (floor) or is it just the furnace block?

if just the block, know this is probably due to vibration and uneven weight of the HVAC combo. I'd band it with some of that stainless steel pallet banding, and before tightening, shoot a little polyurethane caulk/fill in there. leave the band on. somebody will probably need to lean on the furnace to raise one side slightly as you tighten.

if through the pad, I'd get a pastry bag full of red-bag sand mix, 5000 pound test stuff, and fill the cracks until they bulge, then wipe level with a putty knife or trowel.

sig: if this is a new economy, how come they still want my old-fashioned money?
Dec 05, 2013, 12:53 PM
Thanks for the fast response.

It is just the block that has the crack.

I will look into pallet banding, hope they have such a thing at Lowes/Home Depot.

Dec 05, 2013, 08:51 PM
It's not supporting any real load, just the weight of the furnace in compression. It's painted, so any repair can be easily covered.

No need to get too fancy with this. Inject some epoxy to help hold the pieces together then fill with a two part epoxy filler. The banding is a good idea but may or may not be needed.