Home Maintenance Tips to Prevent Wet Basements
by Merv Stark, Calgary Home Inspector.
There are various items of concern that I have encountered, as a Registered Home Inspector (RHI), over the past several years that are ongoing at homes that I inspect. This spring may become challenging as we have had to deal with increased amounts of snow on roofs, snow in yards that has turned into ice trapping the melting snow water and preventing it from going away from homes, plus frozen downspouts which prevents water from being expelled from the surface area. I expect to see more water around the perimeter of homes this year than I have seen in the last several years of having done inspections. I have heard many stories from past clients about water damaged basements and as this is a concern that usually has easy exterior remedies, I have put several diagrams and pictures in this article for your convenience and understanding.
The gutters on your home are very important. These are installed around the home by the builders who also provide downspouts that extend away from the home so water will not come back towards the foundation. Occasionally I have found gutters full of leaves, dirt, past construction materials and/or with tennis balls and children’s toys. I have even had trees over a foot tall growing in gutters! Gutters should be cleaned annually so water can flow proper.
Ice in Downspout
In the late winter/early spring time, I find most downspouts not in use or frozen shut with water spillage backed up to the foundation wall. Some downspouts have been blown open several feet above the ground from the freeze/thaw cycle that can occur daily during our winters in Calgary and area. A lot of downspouts have had the elbow installed too low so the entire downspout makes soil contact. Ground level spouts will freeze up quicker than a downspout that is elevated at the discharge end. Our wonderful Chinook winds cause roof snow melting but with the frost remaining in the ground, downspouts at ground level can freeze up. The warm Chinook air flow should be allowed to go around the entire pipe creating a continuous melt within the pipe.
Downspouts that discharge into a weeping tile (Black corrugated pipes that are vertical and general found at newer homes at basement window well areas and at downspout discharge locations) can also freeze shut near the top.
Note: This particular weeping tile does not have a cap on it. Children can drop rocks and garbage down them preventing their ability to drain the water properly away. Water can then seep into the basement.
Note: This picture on the right is designed for summer discharge. I prefer the discharge opening not to touch the ground during the winter, but you must be careful of a possible trip hazard. Also you should not drain onto a sidewalk where the water could freeze causing a slippery ice trip hazard. Frozen ice on the concrete will also eventually cause damage through surface damage and possible cracking since the water may get under the concrete and can cause the concrete to heave, thus creating cracks. Ask your home inspector for a possible solution if he does not volunteer a comment.
A good builder will provide a proper graded ground slope for this water drainage to leave your lot. However, the ground around the new home will settle after a few years and a reverse drainage system may develop. This settlement can be several inches as noted in the picture below and I am always surprised how many people do not notice or do not care. Now add the fact the neighbor may have added soil around his home. You now have potential for a moat around your castle. Soil must be added and graded to bring a proper slope away from your home.
The season for potential water in your basement is now coming to a basement near you. Are you ready? A comment that I put in my reports for my clients contains the amount of water that an average lot is exposed to throughout the year, as reported from Canada Mortgage and Housing Corporation, CMHC, a strong supporter of the Canadian Association of Home and Property Inspectors, CAHPI. Monitoring your home is discussed below may prevent water damage.
- It should be understood that it is impossible to predict the severity or frequency of moisture penetration to a home. Almost all basements exhibit signs of moisture penetration and virtually all basements can indeed leak at some point in time. Further monitoring of the foundation will be required to determine what improvements, if any, will be required. Basement leakage rarely affects the structural integrity of a home.
- The vast majority of basement leakage problems are the result of insufficient control of storm water at the surface. The ground around the house should be sloped to encourage water to flow away from the foundations. Gutters and downspouts should act to collect roof water and drain the water at least five (5) feet from the foundation or into a functional storm sewer. Downspouts that are clogged or broken below grade level, or that discharge too close to the foundation are the most common source of basement leakage.
- In the event that basement leakage problems are experienced, lot and roof drainage improvements should be undertaken as a first step. Please beware of contractors who recommend expensive solutions. Excavation, damp-proofing and/or the installation of drainage tiles should be a last resort. In some cases, however, it is necessary. Your plans for using the basement may also influence the approach taken to curing any dampness that is experienced.
- Annually the province receives about 355 millimeter of rain from May to October. On a typical 40 x 110 foot lot, this will produce 144,800 liters of water.
- 6 millimeter of rain on the 40 x 110 foot lot would produce 2,596 liters of water.
- The 355 millimeters of rain on a roof of a 2000 square foot house would produce more than 167,200 liters of water, which must be directed away from the foundation of the home.
- The 6 millimeters of rain on the same roof would produce 1,200 liters of water that must be directed away from the foundation of the home.
Preventing Wet Basements: Causes
Wooden Decks and Water Drainage
Another potential water problem I encounter is wooden decks that have the house drainage beside the deck. The soil below a deck is very rarely graded for water to be moved away from the home. With soil settling under the deck, causing low surface areas, the water will go under the deck creating ponds where it slowly evaporates. This picture shows the water draining directly under the deck, it has no ventilation and will quickly rot due to the moisture trapped under the deck. Grading should be planned and maintained around your entire home including under all decking. The grading of the property can determine where the water will go!
At least this elbow is not pointed at the basement window. The potential for the discharge water to freeze on the sidewalk is a concern. The window well is inadequate as a frozen surface could allow water entry that can freeze in the pit opening. Water may have gained access to this area in the past and lifted the sidewalk creating the crack as observed in this photograph.
Several years from now the crack may be bigger, chipped out, and several years after that you may get two elevations creating a possible trip hazard. To repair a poured sidewalk, you will need to get someone to jackhammer out the concrete, remove the debris, add gravel, new rebar, then pour new concrete. The cost may easily be over a thousand dollars. I think the downspout relocation would have been a more logical choice a decade earlier and could have been done with basic tools on a warm sunny day when you could have also bought a few extra feet of downspouts.
Let’s use a different scenario. Our first spring rain, and it’s a heavy downpour. Frost is still in the ground. Soil is right up to the window. Guess where the rain water will go! Your home inspector should recommend you remove several inches of soil below the window and install a window well if needed.
Spring is a time for enjoying the out of doors and doing some home and yard maintenance. Caring for your home by insuring that your gutters are cleaned before the winter, that your downspouts are installed properly with drainage away from your home and walkways, that proper grading away from your home is maintained, and window wells are protected from excess water will allow you to put on the warm weather gear and enjoy spring in Calgary rather than watching the moat grow around your home, and clean up the water mess in the basement.
Merv Stark, Starkpro Property Inspections, CAPHI -RHI