Because homes and contractors can be confusing, we try to answer all building questions that come to us at Armchair Builder. We recently received a question from a new home owner in Illinois regarding settlement and a high water table. This new owner is concerned that a high water table may be causing the foundation to sink which is showing up in cracked caulk in trim and sticking doors. Here is the question from Richard H. and the Armchair Builder response.
My family just moved into a brand new 6,500 sq ft house in Illinois built by Toll Brothers. When we finished our basement, and installed a ejector pit, the water table was so high that we have to put weights down to set the pit. We installed 2 sub-pumps and have battery back-ups on both as well as a whole host generator. The pumps constantly go off.. like every 20 mins. When it rains, they both go off every 20 SECONDS. This is unsettling.
We are on clay. But there seems to be a high water table under our house. All our downspouts go into a underground hard pipe that takes water far away from house. We have had some settling in the house with crown that cracked at the chalk. A couple doors do not close tight or won’t close. The house is less than a year old. There’s a part of me that knows all houses settle, then there’s another part that is wondering if the house is shifting because of the water table. I have no clue who to call? What type of person can check the level of the house and then come back at a later time and know if it shifted? Then how do we fix the water table so the pumps don’t keep going off. Any suggestions are appreciated.
The Armchair Builder response…
The cracked caulk and sticking doors are quite normal on a newly built home due to the lumber drying out and shrinking…so don’t worry too much about those. That being said, it is possible that you could possibly be seeing some unwanted movement in the foundation. The best way to determine this is in the basement walls…but since you finished your basement, do a walk around the perimeter of the home. The exterior foundation wall exposed from the ground level up to the siding material will tell you if there is unwanted settlement. Look for any visible cracks in the wall (or brick if that covers the wall there). Cracks aren’t necessarily bad, but moving cracks are. So note any cracks you see and then monitor them for widening gaps or sheer movement over time. If the cracks do appear to be moving, you will want to consult with your builder. Most new homes come with a five or ten year structural warranty that will cover this issue.
Regarding the water table, it sounds like your system design is working as intended. There’s really not much you can do about the water table. Trying to change the water table is like trying to stop it from raining. All you can hope to do is manage the water after it gets to your home. Basically, the foundation drain collects the water, transports it to the sump crock and then the pump sends the ground water out away from the home.
One thing you didn’t mention is the exterior grade around the home. It is extremely important that your grade takes all rainwater away from the foundation…that is an item you may want to consider. The grade should slope a minimum of 6″ away from the home within the first ten feet and then direct the water to a drain or off the lot…this is critical to avoiding basement water/structural problems. Also make sure the landscaping doesn’t negatively affect this requirement.
Do you have questions regarding your new home, project or product? Feel free to shoot us an email. Are you thinking of building a new home, check out some of our resources at the Armchair Builder E-store.