Choosing the right remedy for a wet basement is important first step to recover from basement water damage. Another interesting article about Wet Basement by “WEATHERPROOFING” by “Time Life books“, little spinet from the book for our readers

The causes of a wet basement generally lie outside it, but even the best landscaping and gutter system may not solve the problem, and often cracks or holes in basement walls admit water that otherwise would stay outside. Much wetness can be eliminated by fixing interior walls,but work on the exterior may be necessary.

If the basement is damp but not wet you see no patches of water but feel excess humidity or see its effects in mildew the steps are fairly simple. Dampness may arise from water vapor generated by appliances in the house such as dish and clothes washers clothes driers are the worst offenders and their exhausts should be vented outdoors.

Seepage through walls of floor may introduce water as well as humidity, and sometimes humid air generated inside the house may condemns into liquid on masonry surfaces, suggesting that moisture is entering from outdoors. To determine whether the problem is inside or outside—and whether ventilation is a sufficient solution –perform the following test. Tape a 16 inch square of heavy plastic sheeting to the wall below ground level.

Remove it after several days: dampness underneath means that water is seeping into basement between grains of sand and cement in a wall that looks solid. If the plastic –covered areas is dry and the wall around it is damp, then water is condensing from moist air that is inside the basement.

If seepage is the problem, you may be able to block it with a coat of waterproof cement paint or, if necessary, layers of patching mortar over masonry interior walls and floor.  A dirt floor is a common source of seepage; if you have one, covering-concrete or, at the least, roll roofing.

Cracks are more serious than seepage or condensation. They can be caused by settling, infiltrating tree roots, water pressure against walls or floor, or even by minor earthquake tremors.

You may first notice a crack on a rainy day as water streams into the basement. The flood can be stopped and the crack fixed by channeling water out through a short hose, then plugging the leak with hydraulic cement, which hardens on contact with water.

Once the crisis has passed-or if you discover the crack before it floods the basement –check to determine whether it is a moving crack or a stationery one, since each type cells for a different remedy . Mark the wall or floor on each side of the crack and carefully measure the distance between marks. Remeasure the distance after two weeks. If it is unchanged, the crack is stationary.

A change in the space between the marks indicates a moving crack. Try repairing stationery cracks from the inside of the basement first (opposite). If such a patch proves ineffective by itself, the crack probably extends through the wall and you must seal the outside of the foundation too. A concrete patch will work for most cracks, but if the exterior wall of the foundation is badly damaged, you may have to excavate, patch and seal a large section of the wall.

Moving cracks almost invariably go through the wall. To seal hairline cracks effectively, you must make flexible interior patches out of fiberglass cloth and asphalt sealer. You can seal cracks up to an inch wide with mastic joint sealer, which is heated with a propane torch until soft and pushed with a putty knife into the crack. The mastic is then covered with a patching mortar.

Of all the cracks in a basement, the most troublesome are those that occur where the floor meets the wall. Try filling them with a joint sealer and epoxy resin, which are in turn covered by mortar. If this remedy falls to keep the basement dry, the only solution is to install a sump pump.

PREVENTING SEEPAGE:

Dampen the wall with a moist sponge and trowel on a ¼ -inch layer of patching mortar mixed with a waterproofing additive such as silicone or latex. Work   from the floor upward. After the cement dries but before it sets-about 20 minutes to one hour use a stiff brush to apply a coat of waterproof cement paint. Working the paint into the fresh cement.

PATCHING STATIONARY CRACKS:

Open the crack with a cold chisel (right) until it is an inch wide, then remove loose concrete with a wire brush. Use a pointing trowel to wet the surfaces of the crack with patching mortar; then fill it with the mortar

SMALL EXTERIOR CRACKS:

Excavate the wall a foot below and a foot beyond either side of the crack, then build a three-sided form. Cut 2 -by-4s long enough to reach between the bottom of the excavation and 1 foot above the crack. Nail to these edges ½ – inch plywood the length of the 2-by-4s and 2 feet wider than the crack. Prop the form over the crack with 2-by-4 scraps and fill it with a standard concrete mix. Let the concrete set 24 hours before removing the form.

FILLING WALL –FLOOR CRACKS:

Widen the outside of the crack with a cold chisel, making a bevelled slot. Dry the crack with a propane torch and line the slot next to the wall with a strip of mastic joint sealer ¼ inch thick to keep out moisture. Half fill the rest of the slot with epoxy resin to prevent the mastic from loosening, then mortar over the resin with a pointing trowel.

REPAIRING SMALL MOVING CRACKS:

Cut fiberglass cloth-the kind sold for patching walls –to cover the crack completely and extend at least 2 inches on all sides. Using detergent, clean the crack and the part of the wall to be covered by the patch. Brush on a coat of asphalt sealer, stock the patch to it, and cover it with more sealer.

PREPARING THE CRACK:

Chip out the crack so that it is ¾ inch wide at the bottom and 1 inch wide at the surface of the wall. If the wall is cinder block, cut strips of expansion joint material, an asphalt-impregnated substance used between sections of sidewalk. Stuff the material through the crack –using a screwdriver, if necessary- to fill the hollow inside the block

SEALING THE CRACK:

Use a propane torch with a wide tip to heat mastic joint sealer until it is soft, and then press it into the crack with a putty knife. Fill the crack about halfway, then, with a pointing trowel, fill the crack to the top with patching mortar to complete the job.

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