Not surprising for a city known for its architecture, there is a wide variety of housing styles in Chicago. Bungalows, two- and three-flats, graystones, Chicago cottages, Georgians, ranches, Cape Cods and many other styles are sprinkled throughout city neighborhoods, often with several styles found in one block.
There’s not quite as much variety among the foundations that support these houses. The most common residential foundation in Chicago is one built with poured concrete although a trip into the basement of older homes may reveal a concrete block foundation or other types of masonry including stone, brick or a webbed terra cotta block known as “telephone tile” from its use as an underground wiring conduit.
One thing is true of all types of foundation in Chicago: someday, somehow it’s probably going to leak. With poured concrete foundations, the leaks most often arise from non-structural cracks in the walls but can also come from cracks in the basement floor, through the cove joint or over the top of the foundation wall. For a home with a block or other masonry foundation, floor and cove joints can leak, too, but seepage can also come from deteriorated or cracked mortar joints or through porous masonry.
Of course in any foundation, poorly fitted windows, unsealed openings for pipes and utilities and clogged or absent window well drains can also cause leaks.
Regardless of the type or source of leak in a Chicago foundation, there is a way to repair it permanently and keep the basement dry and safe.
One problem with repairing leaky foundations in Chicago is the narrow width of city lots and the resulting proximity of house to one another, making outside work difficult. Fortunately, many methods of repair for a leaky foundation are done on the inside – but not all.
Interior Repairs – The most common way to stop leaky foundations is interior crack repair, which is done by injecting a non-structural wall crack with expanding polyurethane to fill it all the way to soil outside. This permanent seal remains flexible after it has cured to prevent minor foundation movement from re-opening the crack.
Another effective, permanent repair is to install interior drain tile to stop leaks through floor cracks and/or the cove joint. Interior drain tile, which is perforated pipe installed in a bed of washed stone under the basement floor, relieves the hydrostatic pressure that causes the leaks and carries the water to a sump pump for disposal.
Exterior Repairs – Sometimes those wall cracks aren’t accessible from the inside and must be repaired on the exterior using sodium bentonite clay. A small hole is dug next to the foundation at the site of the crack and is filled with the clay to create a permanent “positive side” barrier against water.
Stopping seepage through masonry walls and over the top of the foundation is also done outside by installing an exterior waterproofing membrane. A thick coat of asphalt-modified polyurethane, the membrane is troweled onto the foundation wall to form an impenetrable barrier against water. In cases where a lot of ground water is present, exterior drain tile can be installed along with drainage board to protect the membrane and channel rain water downward.
Whether the work must be done on the inside or the outside, a Chicago homeowner who needs to repair a leaky foundation needs the advice and assistance of a basement waterproofing contractor that knows Chicago’s homes and their foundations. At U.S. Waterproofing, we got our start in Chicago 56 years ago and we have repaired leaky foundations all over the city, permanently and cost-effectively. Why not ask for our free advice?
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