Question
Patio puddle
Last week we had a concrete patio installed that runs the length of our house, and the day after it was done we noticed that water pools about half an inch deep in one corner. Even in 90 degree heat, it does not entirely evaporate. Please inform me of any possible resolutions the contractor might suggest to fix this and which is the best way to go. While trying to learn more about this, I realized that I do not see expansion joints on the entire surface or near the house, so now I have doubts about the integrity of the entire job. I asked about the joints and was told that there is support in the internal structure, but from what I've read, it seems like I should see evidence on the surface. Any suggestions would be greatly appreciated.
AnswerErica:
If you don't get immediate acknowledgement that they plan to fix this, I would threaten to file suit immediately in a certified letter, I would also threaten to call BBB and file a complaint with local permitting authorities (the City). They absolutely must have expansion, contraction and control joints in all concrete slabs more than 10x10feet, no matter what is in the slab or what climate you live in. I don't care what they say. If they tell you otherwise they are either grossly incompetent or worse they are liars and cheats. They also clearly did not provide positive drainage for the slab which is a basic requirement for any patio.
Unfortunately there is no easy fix. Control joins can still be cut if the concrete has not already cracked. Look for hair line tiny cracks. Concrete always cracks as it cures because concrete shrinks, that is why we cut or place control joints to control where it cracks so it looks good. Typically control joints are troweled in the wet concrete or cut into the surface within 36 hours of placement so no cracks form. However expansion and contraction joints are needed every 30 feet and they cant be added afterwards.
As for the low spot, depending on how much depth of concrete you have and the elevation change needed between the low spot and the edge of concrete you might be able to get the concrete ground down with a large rotary grinder and then sand blast all of the slab so it looks the same...however its probably cheaper to rip it all out and start over or coat it with "cool deck" or some other concrete coating material.
I wish there was a better answer for you. Seen this a lot.
Best Of Luck
Sean J Murphy, LA, ISA, LEED AP
www.seanjmurphy.com
