Water can only enter the basement through some type of opening. The most common openings allowing water to enter are foundation cracks. It is very common for concrete to crack, in fact it is a natural occurrence. Concrete expands and contracts naturally, but it is not very flexible so it cracks. These cracks most often travel from top to bottom and all the way through the wall. When the wall is in contact with wet earth it simply leaks.

The second most common reason for water in the basement is a leaking tie hole. A tie hole is part of the original fastening system used to hold the concrete forms in place while the concrete is being poured and to hold its form while it’s curing or hardening. These tie holes are placed every few feet at different levels. When the forms are removed leaving a new foundation, the tie holes are often simply filled with cement or not at all. Cement does not always make a watertight seal and subsequently may be the cause of the water in the basement. The third most common problem is hydraulic pressure from under the floor. This pressure causes water to come in along the outside walls, or appear in the middle of the floor.

FOUNDATION CRACK

Water usually enters the basement through some of type of opening or penetration. The most common type of opening is a Foundation Crack. A concrete foundation will crack because concrete expands and contracts. Concrete is not very flexible so it creates expansion joints for itself in the form of cracks. This is to accommodate the movement of the wall, making them a natural occurrence and very, very, common.

TIE ROD HOLES

The second most common reason for water entering the basement is a leaking tie rod or tie rod hole. Tie rods are the fastening system used to hold the forms in place while the concrete is being poured to make the foundation. After the concrete sets up the tie rods are removed or snapped off. These rod holes are either patched with plugs and hydraulic cement or if left in the wall are often not treated with any waterproofing measure at all.

ELECTRICAL AND PLUMBING PENETRATIONS

Another common problem is leakage from a plumbing or electrical penetration. Hydro is often brought to the panel underground and the hole in the foundation can leak as would a plumbing penetration.

THE SILL PLATE

The sill plate is the joint where the house sits on top of the foundation. This is a joint where two dissimilar materials come together with different rates of expansion and contraction. This joint is usually covered with cement parging and can crack allowing water to come into the house.

WATER COMING UP FROM UNDER THE FLOOR

This problem is very common in rural areas and in areas with higher then normal clay content.

Tree roots, mud and age can also plug or collapse weeping tile. This would prevent water from being carried away from under the house causing water to come up from under the floor.

CONSTRUCTION OR CINDER BLOCK FOUNDATIONS

The construction block foundation is made of hundreds of individual brick like blocks. They have mortar joints around four sides making many hundreds of joints that can leak. The construction block wall is hollow so small leaks on the outside can fill the blocks with water. This water will enter the house wherever it finds an opening or crack.

It is a common misconception that grading the land so that it slopes away from the house will somehow prevent water from coming into the basement. The truth of the mater is that at some point the ground against the foundation is going to become saturated with water and if wet earth is in contact with a crack or other penetration it can leak. Sloping the earth away from the house will also not prevent water from coming up from under the floor.