By Mitch Kuffa
Let’s answer some questions from our readers.
I noticed that my rear concrete patio, the sidewalk at my front porch and the garage slab near the house all appear to be settling. What’s going on? Is my house moving?
This type of movement or settlement is somewhat common and may need attention, but your house is most likely stable.The reason this type of settlement occurs is relatively common with houses that have full basements and is due to the following.When your house is being built, a survey crew comes out and marks the corners of the house for the excavator (who will soon dig the basement). Typically, the excavator will dig the hole 3 ft. to 6 ft. wider in all directions than the actual foundation size itself. The reason he digs it larger is because the men installing the foundation walls need room to work. When they have completed their job of installing the foundation walls, the municipality inspects the work and approves the hole for a backfill procedure.
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HERE IS TYPICALLY WHERE THE PROBLEM OCCURS:
The next sub-contractor on the job site is the grading contractor who shows up with his bulldozer and pushes the dirt back into the hole around the house. This area is approx. 8 ft. deep and the dirt is very difficult to compact without damaging the new masonry foundation walls. The backfill and uncompacted soil runs around the house approx. 3-6 ft. away from the foundation.Now the garage, porches, etc. are added to the existing foundation and are partially placed on disturbed soil. If the ground happens to have a high clay content the condition is even worse because clay does not compact well and many times has voids between the chunks of dirt used as backfill.Over a period of time, the area around the perimeter of the house, compacts and settles and anything installed in these areas that does not have a formal foundation moves down with the dirt (such as sidewalks, concrete slabs, flowerbeds, a/c units, etc.).How can this condition be corrected? If can’t. The sidewalks, garage, etc. should have been built differently from the start. Now that everything has settled you should be able to theoretically remove the sunken areas and replace them conscientiously (with metal re-enforcement, compacting the sub-soils as best as possible, etc.).
I live in a rented duplex that was built on a crawl space. I have lived here for 3 years and no one has ever entered the crawl space during that time. I wonder if it should be inspected on a regular basis to make sure things are OK. Should I address this with my landlord or is it OK to let the crawl space sit until there is a real reason to go down there?
Crawl spaces are the most neglected and avoided areas of houses in general. People just do not like to frequent this area. Unfortunately however, there are a multitude of things to see in this dark, typically moist and warm area. Approx. 90% of all crawl spaces that I have the opportunity to look into have important concerns that need to be addressed.Crawl spaces commonly are dirty, wet, have hanging electrical wires, disconnected duct work, broken vents, have framing concerns, etc.. Also, you want to make sure you have no plumbing leaks. I have seen many times where there has been an on-going plumbing leak that nobody realizes. Any damp areas not addressed can also lead to mold/mildew conditions not only in the crawl space, but up in the living area.So, to answer your question, the answer is yes. You should encourage someone knowledgeable to visit this area twice a year.
Mitchell Kuffa Jr. is a licensed builder who performs private home inspections.