Expert: Bruce E. Johnson - 5/25/2009

Question
I recently bought a 60-year old house and I have a 30x12 patio in my back yard that has settled and, around the middle, has a slope towards the house.  As a result, there is water pooling by the house wall every time it rains.  The house basement is dry. The patio has flagstone with cement in between the stones and there is a knee-high & 1' thick brick wall around it.  I do not know if the flagstones are on top of a concrete slab or not.  I would like to correct the slope either by fixing the existing patio or by replacing it completely with a new one.  I had one contractor look at it who told me that it cannot be fixed and has to be replaced.  He estimated the cost of removing the existing patio and pouring a concrete slab to be $6,000.  That does not include replacing the flagstones.  He also told me that he would not be able to salvage the brick wall and it would have to be replaced too (not included in the cost).  I am not convinced that the brick wall cannot be salvaged and I am a little skeptical about his recommendations because he was trying really hard to convince me to remodel the landscaping of the entire back yard.  I got the impression that he was not really interested in fixing the patio's slope but he wanted to turn it into a much bigger job.  Any suggestions about my options?  Is the $6,000 estimate reasonable for removing the existing patio and pouring a concrete slab?  Also, it sounds odd to me that the brick wall cannot be salvaged.  Even if there is concrete under the flagstones that needs to be jackhammered, can they use a concrete saw near the wall to avoid damaging it?  I will ask for more estimates but I would appreciate any suggestions/tips so that I can make a more informed decision.

Answer
Hi Emmanuel, the cost of pouring a patio should run around 5-7 dollars a square foot or about a third of what the contractor is bidding. How much tear out and unforseen circumstantial work is needed above and beyond that I cannot say without seeing just what is entailed in the project. If you are going to do something with the patio anyhow, why not try to pull up one of the flagstone and see what is under it.  If it is concrete then you probably need to tear it out and redo it.  Tear out of a concrete slab will cost 2-4 dollars a square foot if the person doing the work hauls the debris away..so that will add another thousand dollars or so to the project. If the flagstones are just set on a sand base then you can just pull them up, level out the sand and then reset the flagstone. I don't know how the brick wall fits into all of this but it can probably be salvaged if it is not structurally tied into the patio.  I hope this information helps feel free to write again regarding this or other matters, sincerely bruce e johnson..bejohnsonconsulting.com