Thread: Garage Floor Cracks - New Construction

New home with garage concrete deck cracking parallel to rear house wall, also down the middle. I'm thinking the heavier heated section of the house settled causing the thinner garage concrete deck to crack under the stress. Thoughts?

Similar Threads:

• Pull down stairs in the garage- fire rated?
• CPSC Recall: Floor Electrical Outlets
• Grandma's Garage Explosion Story
• Garage Door reinforcement
• Avoiding construction defect lawsuits - Contractor Mag

I don't see a control joint. That would explain the one down the center of the slab.

Are those moisture stains around the crack in pic #2?

Maybe its the weight of the water heater sitting directly on the floor.

50 gal. at 7+lbs. / Gal. + the tank vessel. Nope that shouldn't have done it.

Was there any cracks in the exterior foundation beam walls opposite those cracks?

Those look larger than the normal to observe curing cracks.

Originally Posted by Randy Moore

New home with garage concrete deck cracking parallel to rear house wall, also down the middle. I'm thinking the heavier heated section of the house settled causing the thinner garage concrete deck to crack under the stress. Thoughts?

I would recommend that an engineer and the builder be called to address this issue. I have seen in several instances, where during the initial pour of the main slab, the cement truck parks right where the garage floor is supposed to be. After the main slab is poured, the truck moves, the displaced soil is raked back into place, not compacted, and then the slab is poured for the garage.

If you were to drill a few holes near the cracks, you would probably find out that the slab is only 2 inches, or less, thick.

Originally Posted by Eric Van De Ven

I would recommend that an engineer and the builder be called to address this issue. I have seen in several instances, where during the initial pour of the main slab, the cement truck parks right where the garage floor is supposed to be. After the main slab is poured, the truck moves, the displaced soil is raked back into place, not compacted, and then the slab is poured for the garage.

If you were to drill a few holes near the cracks, you would probably find out that the slab is only 2 inches, or less, thick.

Rick - I looked hard at the foundation but didn't see any cracking there.

Eric - good call, that was my recommendation. My thought is that the builder went cheap with a too-thin garage slab that couldn't take any settling stress, especially if the heavier house settled a bit. I'd like to see the eng analysis.

A lot of times if re-bar dowels are not put into the foundation when the floor is poured there will be settling at that area resulting in that crack.