Prevent water seepage through concrete block foundation

Question

Earlier this week we had a really warm day which was welcomed by many after such a long cold winter. That night I came home to find a small puddle forming on my basement floor. I followed the water back to an unfinished corner of the basement and pulled back the insulation to find a half a dozen or so wet concrete blocks.

This is the first time we have had water in the basement and my guess is with the warm weather and the only thaw piece of ground being next to the foundation, the water only had one place to go and after the ground got over saturated it began to seep in.

This spring, I plan on revisiting the landscaping in this corner of the house to look for low spots in the grading and drainage. We do our best to keep our gutters free from ice build up and what not, but are there additional things I can do to prevent water seepage through a concrete block foundation?

Answer 1

This time of year is prime for water seepage into unsealed foundations. With water tables on the rise and the top of the ground still frozen, there tends to be less natural drainage and a bit more water pressure on foundations. This is also a bed time of year in northern climates to improve external drainage. A good drain tile around the foundation directed away from the building or a sump pit pumping water away from the house is the usual method. Since that is not your best option now, the other option is to treat the interior of the foundation with a hydrolic sealant like DriLoc. Driloc and products like it are applied like paint to masonry surfaces and will protect against leaking for up to 4 or 5 PSI external water pressure. The external pressure of ground water against the walls is usually very low, under 2 PSI, so this product is very effective. The only problem is that the surface should be dry when you apply it. You may have to suffer through the current situation for a bit until the surface can be dried. When you do apply Driloc, it is important to clean the surface well, remove any and all efforant mineral deposits, old paint etc. When applying the product, work it into all the tiny holes of the masonry. Pay special attention to joints between walls and floors. Two coats is normally necessary.

Answer 2

As @shirlockHomes said, driLoc is your best patch solution.

The only true preventative is to excavate around the outside of your foundation and seal that surface, and / or place another impervious moisture barrier like a plastic sheeting.