Obvious Signs of Concrete block / Cinderblock Foundation Leakage

There is no denying it, if your foundation walls appear in any way similar to the images above, you have visual confirmation that your concrete block / cinderblock walls have water trapped inside the blocks and it is highly likely that you have at least occasional basement leaks, and/or water entering your home beneath the basement floor slab, and unfortunately, the ideal conditions for the premature deterioration of your foundation walls.

The illustration below depicts the typical flow of water within concrete block basement walls (double click the image to enlarge it).

Why Concrete Block / Cinder Block Foundations Leak

Concrete block foundation walls have an inherent weakness in that there are mortar joints on all sides of the blocks (the same as any brick wall). There is a general tendency for mortar joints to develop hairline cracks over time, typically due to the thermal cycling of the blocks and the mortar, in this case, due to two slightly different materials expanding and contracting at different rates. Note: A drop in the footing supporting the very base of the foundation also results in mortar joint and block cracking. Below grade hairline cracks in the mortar joints, and cracks in the blocks themselves, are constantly subjected to hydrostatic pressure from the water table surrounding the foundation, thus facilitating the entry of water into what are essentially hollow blocks. Below are images of the concrete blocks / cinderblocks that are used in the construction of a foundation wall (this foundation wall type was in widespread use in residential construction between 1950 and 1980).

Injection of Leaking Concrete Block Walls

Homeowners are increasingly aware that pressurized injection (epoxy and polyurethane) is a very economical way to waterproof a leaking basement; consequently, we receive numerous requests for the injection of concrete block / cinder block walls; unfortunately, pressurized injection is not a viable option for concrete block foundations because the blocks are hollow making it impossible to ensure that the injected resins will remain contained in the area(s) where water is able to penetrate the concrete block foundation.

The Application of Sealants on Leaking Concrete Block Walls

Some seemingly knowledgeable people, and companies, would have you believe that the application of a sealant or tar based product on the inside surface of a concrete block or cinder block wall will remedy your leaking basement. While this type of repair may temporarily resolve a basement leak, this form of basement waterproofing will, in fact, trap water within the block foundation wall effectively preventing any evaporation of the moisture trapped within the blocks. As concrete is a porous material, the resultant pooling (entrapment) of water within the block wall will accelerate the deterioration of the blocks possibly to the point of failure, leading to far greater repair costs with the passage of time and potentially the structural failure of sections of your foundation walls. Surface sealants must be applied on the exterior wall surface, or the side of the wall where there is positive pressure.

Professional Methods Used to Waterproof Concrete Block Foundation Walls

Logically, foundation damage and water penetration of the block would be averted by preventing water from entering the concrete blocks in the first place; this is accomplished by external excavation and waterproofing. Alternatively, entrapped water in a concrete block wall can be purged by installing an internal de-watering / perimeter drainage system; both of these waterproofing approaches will greatly decrease the rate of deterioration of your foundation. Over the years we have encountered numerous situations where foundation walls need to be rebuilt or reinforced to avoid foundation failure (often the result of years of neglect of a known problem); the cost to rebuild a wall or to reinforce it is significant; you want to avoid such a situation if at all possible.

Factors Affecting The Selection Of The Most Appropriate Repair Method For Leaking Block Foundation Walls

Fortunately, it is possible to fix concrete block / cinderblock wall leaks permanently. To determine which waterproofing technique is the most appropriate to your circumstances, either external waterproofing or internal de-watering, a number of factors should be taken into account:

· Whether the basement is finished or unfinished;

· Whether there is visible mold inside the home;

· The moisture levels detected behind finished basement walls (indicates if mould is likely present);

· The condition of the concrete blocks (level of deterioration visible externally and internally, if possible);

· The accessibility of the areas requiring waterproofing;

· Whether or not the water in your basement is a result of a high water table;

· The landscaping surrounding the home (concrete walkways, decks, fence locations, etc.,);

· Your willingness to destroy the landscaping around your home, or to fully remove finished basement walls;

· Your level of concern with respect to the existence of mould behind finished basement walls;

· Your budget;

· Whether you are pragmatic or a purist;

· Whether or not structural reinforcement of the wall is required;

· The need for the installation of a window well drain;

· The desired warranty duration;

· The condition of the existing weeping tile and the efficiency of the existing city storm water drainage infrastructure;

· The extent to which waterproofing is required; and

· The contractor you choose.

As mentioned above, when dealing with a concrete block foundation there are only 2 professional repair options:

· Internal de-watering / installation of a perimeter drain system; and

· External excavation and waterproofing.

How To Proceed When You Are Ready To Address Your Wet Basement Problem

Selecting the most suitable waterproofing option should always be done in consultation with a true waterproofing professional / waterproofing contractor because expertise is essential. While it is true that most general contractors and landscapers can excavate a wall and do waterproofing work that might last a few years, if the basement waterproofing is not done properly, the contractor will have to do the entire job all over again; if you did not have the work done by a reputable and established waterproofing contractor with an excellent rating from the Better Business Bureau, how likely is it that your contractor will acknowledge that they are responsible and do the work again at no charge to you? Additionally, waterproofing work requires skill and experience; the importance of the many minor details involved in basement waterproofing cannot be overstated. In reality, the average homeowner is unable to differentiate between an excellent waterproofing job and a lousy job; consequently, the financial impact of hiring the wrong company can be quite significant.

If you want the best job possible, with a meaningful warranty, call AquaGuard Injection & Waterproofing™ today at 1.888.284.2384.