Wall cracks are caused by settling or improper back filling of a foundation. Wall seams and cold pours are caused by pouring a wall in sections or stages. Honeycombing is caused by improperly mixed concrete and appears as porous areas on a wall.These types of leaks usually leave a stain on the wal land tend to leak most near the floor due to greater pressure. With frequent close observation you should be able to determine whether or not these are causing seepage into the basement.As a general rule it is best to excavate these types of wall leaks and repair them from the outside. There are two reasons for this approach:
- By patching the outside you are restoring the surface integrity of the foundation and preventing water from getting inside the concrete wall andpossibly causing damage to the wall.
- Second, since the majority of homes have outside footing drains, a patch on the outside will force the water to drain where it will be led away as originally intended.
The area to be repaired is first chiseled out. The surrounding area is chipped/scarified to porovide a clean rough surface. After wire-brushing the loose particles off, the wall is acid washed and then rinsed. Hydraulic cement is used to patch the chiseled out area followed by a plaster coat over the patch and the chipped area.A heavy tar coat and a poly vapor barrier are then applied over the entire area and the work area is back filled and returned to original condition.Occasionally a house will have an inside footing drain system under the basement floor for handling groundwater. In this type of system it is possible to repair a seepage problem from the inside. The leaking crack or seam is chiseled out from the inside and a channel is embedded in the wall. This channel is tied into the system under the floor and the wall and floor are then re-cemented. This method captures the water inside the wall and diverts it into the drainage system under the floor. This same method can be used to repair cracks, etc. that are inaccessible from the outside.It is important that there is some type of system under the floor to deal with this water or it could lead to seepage and/or dampness problems. Beware of contractors who, because this is an easier way, divert the water under the floor when there isn't any system in place to deal with it.
Repairs involving excavation can be dangerous and shouldn't be attempted unless you are sure you know what you're doing. Be smart and hire a professional.Eastern Waterproofing Co., Inc. would be happy to quote this type of work for you and provide a reference (over 500) and a free written proposal.