"Understanding Your Home" by Building Inspector Mark Visser
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Negative grading is where the property is sloped towards the house instead of away from it. It can lead to all kinds of trouble, see above, including damp or wet basements or lower levels.
A window well is supposed to keep surface water away from lower level windows. Rain water or water seeping in through the the sides should be drained away to the weeping tiles. Installing a window well cover will keep the rainwater out but it takes a bit more to keep surface water away from the window well.
The property should be sloped away (positive grading) from the foundation walls. A slope of 1" per foot for 10 feet would be ideal (25 mm per 300 mm for 3 m). However, this slope may not always be possible due to adjacent land elevations or limited distance from the house to the property lines. If that is the case you may have to install a swale or French drain. For more information go to Grading in the Landscaping and Gardening section.

Not properly fastened.
Pulled away from foundation.
No seal between well and foundation.
Negative grading, settled soil around well. Surface water will flow towards the house and into the well through the wide open space between well and foundation wall.

Window Well Problems and Solutions

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- Window well is installed too deep allowing surface runoff water to enter the well.
- Window well is pulling away from the foundation wall allowing water to run into the window well.
- Water is seeping in the window well from the crack between the well and foundation wall.
- Grading is negative. Water is settling soil around window well. The indentations acts like a funnel and water will wash soil into the window well compounding the problem.

Surface run off water will get into the window well which could lead to all kinds of problems.
Once the finished grade is known the top of the new window well should be 4 inches (10 cm) above grade.
- Remove any screws, bolts or any other fasteners used for attaching window well to the foundation wall.
- Remove some of the dirt from around the window well and try to raise the window well to the desired height. If it doesn't budge remove some more dirt till the well can be raised.

I have seen this many times in my 28 year home inspection career. Usually the top of the window well is pulled away while the bottom is still in place leaving a large pie-shaped opening between the well and foundation. Most likely the window well was is not properly secured to the foundation wall. Because of the large opening soil will be washed into the window where it will settle between the gravel and soon it will prevent the well from draining properly. Settled soil around the well works like a funnel collecting more water and aggregating the situation.
- Remove soil away from the sides of the window well.
- Install a rubber or heavy duty foam gasket to the flange of the well. You may have to fashion your own gaskets as they cannot be purchased.
- Insert a pry bar in the soil at the front corners of the well and wedge it back to the foundation wall. Instead of a pry bar you can also use a shovel but do not use too much force or you will break the handle.
- Once in place secure the well to the foundation wall. You can use Tapcon masonry anchors or legbolts and lead shields.
- The new soil will settle, so check regularly and top up with soil as required so the property will slope away from the house at all times. A slope of 1" per foot for 10 feet would be ideal (25 mm per 300 mm for 3 m).

This is a common problem simply because there is no seal or caulking at the point where the window well is attached to the house. This joint wasn't left unsealed because someone forgot to do it, but simply because no one thought it would be a good idea. Come to think of it, we caulk around windows, doors, and where services enter the house such as central air connections, hose bib, and gas or oil supply lines. We apply caulking in these areas to keep out rain and cold.
- Remove gravel and soil from the window well till the entire well is visible.
- Apply a heavy bead of commercial grade silicone caulking into the joint. If the opening is more than 1/4 inch (6 mm) wide, apply two beads of caulking. Apply the first bead into the joint as deep as possible. Let is dry before adding the second bead. I would not recommend using a backer rod as it may get pushed out by hydrolic (water) pressure from the outside. If the caulking doesn't stop seepage 100% you may have to dig around the window well and apply caulking from both sides. However, don't start digging yet because I think that the main culprit is negative grading, meaning that surface water is flowing towards the house instead of away from it. See information in next section.

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