Building Homes or Extensions/Quality of house construction
QUESTION: We are looking at buying a fairly new house no one has lived in it. It has some fairly long cracks in the basement floor. The builder says that is normal. They are approximately 1/10 of an inch coming from the center of the basement. Is this normal or a defect in the building? Can it be repaired? We would like to have acid wash on the floor and a walk up stairs put in. Is this something that can be done without ruining the structure of the house?
ANSWER: Lynn,it is not unusual for there to be cracks in concrete. If the cracks are thin and the concrete is level across the crack it is probably not a sign of structural failure. Concrete does not like to be larger than 12 feet in any direction without some way to relieve stresses. This is the reason you see joints or saw cuts in sidewalks, driveways, highways, etc The joints are to give the concrete a weakened place to crack in a straight line, rather than a random wandering crack. It sounds like your builder did not require the jointing from his concrete people.
An acid stained floor will not hide the cracks. Any filler placed in the crack will stain as a different color. The cracks will transfer into any topping cement. Only you can decide if it is a deal breaker or not. I would not expect the cracks to get wider. Again, they are probably typical shrinkage cracks.
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QUESTION: I was wondering also how you feel about putting in a walk up entrance from the basement? I would not want to ruin the house structure.
Lyn, this is a fairly common design on older homes. The big issues are not so much structure as water. It will require due diligence to get the wing walls properly flashed and adequate drainage for the inevitable rain and snow intrusion. I don't think code will allow you to tie the drain to the sanitary sewer and will probably require a separate solution.
Cutting a hole in the side of the basement wall will require the services of a strucural engineer to satisfy your local code authority, but is quite do-able.