Is My Foundation Failing?
My home inspection clients here in the Buffalo and Western NY area understandably have heightened senses when it comes to any problems with the major structural systems of their new home, especially when it comes to the foundation. Major foundation repairs can be very expensive and no one wants to face a huge bill as soon as they move in! Probably over half of the homes I inspect have some type of problem with the foundation. “Problem” doesn’t mean that the foundation is about to fall apart, that the basement will leak profusely or that the house is unsafe. It does mean that I note something about the foundation in my inspection report and recommend next steps. What are the most common defects that I encounter with foundations and should you be concerned about them?
Vertical Cracks in Poured Concrete Foundations
Absolutely the #1 foundation condition that I encounter in any home inspection is vertical cracking in poured concrete foundations. Almost never does this type of crack represent a serious problem to the home’s structure, but they often are a source of water penetration into the basement. Vertical cracks typically occur shortly after the home is built, and are caused by shrinkage of the concrete as it cures and by settling of the home. Vertical cracks typically can be stabilized and water proofed for a reasonable expense. One option for water-tight repair is a polyurethane injection system that can be professionally installed for about $500 per crack. If you are a DIY type, you can purchase a repair kit for about $120 that will allow you to seal one crack.
"Stair stepping" cracks in block foundations
This type of crack looks, well, like a stairway. These are only seen in concrete block foundations (cement masonry unit or “CMU”), and are usually caused by uneven settling of the ground under the foundation. The cracks form in the mortar between blocks, not the blocks themselves. If the crack has been there for decades, without movement then usually they are not cause for concern, but if the crack is larger than 1/8″ or so, or if water is entering the basement through the crack then I always recommend that the buyer have the crack professionally repaired.
Crumbling and damp cinder block foundations
The term “cinder block” is often used to mean any form of concrete block, but cinder blocks are essentially an earlier and cheaper version of concrete block. Compared to modern concrete blocks (also called “cement masonry units” or CMUs), cinder blocks are less dense and as a result are more prone to water penetrating them, and also are not as durable. Many older homes in Buffalo have cinder block foundations. It is not uncommon to see several crumbling or damaged blocks with this type foundation. My advice is to replace any damaged sections and to do your best to drain water away from the foundation.
Bulging or bowing foundation walls
It’s uncommon that I encounter a foundation that has such an obvious problem, but when I do I always recommend that the home buyer or owner contact a foundation repair company for evaluation and repair. Bulging or bowing foundations are unsafe and place the integrity of the upper levels at risk. Professional foundation repair companies often install additional pilasters, or vertical support members, into the ground and against the interior of a bowing foundation. Other bracing methods include installing reinforcing cables, sistering walls or carbon fiber panels.
Old Wooden Foundations
Believe it or not, some homes in Western New York were built on top of wooden, or partially wooded, foundations. Wood foundations have been built this way for many years, but the design of them has evolved over time for the better.
This photo above or to the left shows a foundation a home in Cattaraugus County, NY that was constructed of wood in 1940, and then concrete was applied over the top, or “parged”. The wood appeared to be rotten, leaving me to recommend to my client that he have a foundation expert recommend steps to repair this failure.
A modern version of the wood foundation is known as the “permanent wood foundation“, and is a well thought-out design that offers many benefits of concrete construction. This type of construction makes use of pressure-treated lumber, including plywood and excellent waterproofing techniques.