Basement Floors and Floor Joints Inspection – Signs of Water Seepage
If you find silt deposits at the joint, it is also an indication of some degree of seepage. As the water seeps in from the exterior, the fine silt is in suspension in the water and when the water evaporates, the silt is deposited. Check the joint between the floor slab and the foundation wall for any evidence of water seepage. If you find any signs, record the condition on your worksheet for later correction. The joint should be sealed with hot tar or hydraulic cement.
The floor slab near the base of metal columns tends to develop cracks. Look for such cracks in the floor slab and also look specifically for water stains, efflorescence and silt deposits. Cracks in basement floors are a common occurrence and are usually caused by slight settlement or shrinkage in the concrete. Generally, the only concern with such cracks is that water can seep through them, so they should be sealed.
If the cracks, however, are extremely wide or show signs of heaving, they are of concern and should be further investigated. Most likely, a high water table exerted water pressure pressure on the underside of the slab, resulting in a cracked and heaved floor slab.
If the house has a cleanout and trap for the house waste line located in a pit below the basement floor slab, check to see if the bottom of the pit is dry. If it is wet, it may indicate a high groundwater level or a crack in the drain line. The top of the cleanout should normally be plugged, but some homeowners remove the plug so that the open cleanout can function as a drain if the basement becomes flooded. This, however, is not a good method of eliminating the water in a flooded basement.
If the basement gets flooded periodically and there is no drain in the floor, install a sump pump in the lowest section of the floor so the water can then be pumped out of the basement. Some people consider a sump pump in the basement as an indication that the house has water problems, but this is not necessarily the case. There might have been periodic problems caused by a seasonal high water table, but the sump pump might have successfully controlled the water level. Also, the pump might have been installed as a preventive measure when the house was built. In order to determine whether problems still exist, look beyond the sump pump rather than dwelling on it. Look for signs of water seepage.
Once you have inspected the walls and the floor covering for any signs of water intrusion, check the bases of items stored or standing on the floor for water stains and rust. If you notice that the walls and the floor of the basement seem recently painted, the sellers may have been trying to cover up something. A new layer of paint will cover almost all of the signs of a water seepage problem.
However, there are some areas that are almost always omitted when painting the basement, so be sure to check them for water stains and rust. More specifically, look at the base of the steps leading to the basement. Look in particular at the back of the bottom step, as well as at the base of columns (posts). Wood columns might have stains or might be rotting, while metal columns might be rusting. The base of the inside portion of a sheet-metal casing is also often omitted when painting. Look inside, and if you find extensive rust, it might have been caused by a past flood. On the other hand, it could have also been caused by a faulty humidifier, so try not to jump to conclusions too fast. Ask the seller what caused the condition, when did it occur and whether it was properly corrected. Also, take into consideration the option of waterproofing the basement.