Basement Waterproofing

How to tell if your basement is leaking

Signs of water leaking into a basement may vary between houses. Houses with unfinished basements tell a much clearer story, as water infiltration can be very evident. In the case of unfinished basement, dampness and water accumulation on floors and walls are visible can give simple clues as to the reason for the leak.

Finished basements on the other hand can be a bit more difficult to pinpoint areas of water infiltration. Fully finished basements with subfloors are an example, as moisture and water from leaking foundations can become trapped under the subfloor and persist without giving any warning to the home owner. Under these circumstances, a substantial amount of rot and mold can be lurking on the underside of the finished floor.

If your basement is unfinished look at these common issues;

• Efflorescence
  • Can be described as a white crystalline accumulation found on masonry surfaces, including block walls, poured foundations, and concrete floors. Efflorescence is typically caused by a water soluble alkaline salt that is extruded in the water that is passing though the masonry product. In most cases the salts are described primarily as Sodium Sulfate and Potassium Sulfate, as the water dries on the surface of the masonry product the salt begins to recrystallize on the surface, otherwise known as efflorescence.
• Water seepage
  • Water infiltration can be found on exterior walls and basement floors. Grading issues or plugged window well drains have been known to demonstrate wet areas from around from the middle to upper area of a foundation wall. As the water seepage is caused by overland water, making the wet spots show up higher on the wall.
  • Water seeping from the bottom of the wall where it meets the floor can affect one or more walls. This type of water seepage is caused by hydrostatic pressure.
• Wall cracks
  • Wet sections of a wall that look like its affecting a specific area, are likely caused by foundation cracks or improperly sealed tie holes.
  • On block foundations, cracks can be found in mortar joints as step cracks or lateral sheer cracks, and in some cases vertical cracks spanning though mortar and block are all pathways for water to infiltrate the foundation wall.
  • On poured foundations cracks caused by concrete shrinking, concrete honeycombing and unsealed tie holes are all common issues for water infiltration.
• Paint flaking off masonry walls
  • Paint flaking from masonry walls is a good indicator of moisture. Generally flaking paint will not be isolated in a small area on a wall but rather in a more predictable pattern.
  • Flaking paint can be observed in the bottom 2 feet of an entire wall, in a case like this, the flaking paint is pinpointing the location of the moisture coming though the wall.
  • The reason for the paint peeling, is the efflorescence migrating to the surface of the block, pushing the paint off the surface of the wall.

If your basement is finished look at these symptoms to investigate;

• Wet floor or carpet.
  • In carpeted areas, finding wet areas near exterior walls are a good indicator that water seepage is occurring, either through the floor or foundation wall.
  • With laminate there tends to be a sponginess in the floor as water becomes trapped between the floor and the concrete underneath.
• Discoloration of finished walls, floor or trim
  • Porous material such dry wall and baseboards tend to show signs of moisture absorption fairly quickly, as they both tend to swell and stain.
  • Discoloration from foundation leaks occur near the floor, where the foundation water leak will occur.
• Wet or rotting wood.
  • Wet or rotting wood are both signs of a chronic foundation leak. In the case of rotting wood, the issue has been present for a substantial amount of time, which can mean that there is also a substance presence of mold and bacteria. In either case all rotting should be looked at by a professional, as remediation may be required.
• Rust stains.
  • The presence of rust stains are always caused by moisture. Rust stains on walls and trim can be caused by nails and screws rusting. In the past we have seen a nail of screw driven straight into a waterline or drainpipe, with no signs of a leak until years later. A good way to differentiate a puncture from a foundation leak is if the issue is on an exterior wall. Water and drain lines are found on interior walls while foundation leaks will come through the exterior walls.
  • The moisture caused by a leaking foundation also has the ability to cause fasteners to rust, as well as steel studs. Be aware that a trail of rust is always caused by water, the key is to find out what is causing the water to be there.
• Mold and mildew.
  • Mold and mildew are something that should be assessed by a professional abatement company. Even if you feel comfortable cleaning it up by yourself, it is always important to identify the mold present and understand the associated risks with disturbing the mold.