Issue # 2 Welcome to Watson's Journal!

HOME OWNERSHIP 101: The things everyone else forgot to tell you!

Last month, I talked about "fake" basement leaks, when your walls get wet because airborne summer humidity condenses on them. This month, I want to brief you on real basement leaks. This is a broad subject, and ASHI home inspectors spend long weekends in seminars on basement problems and solutions, but I will go for a brief overview here, with the emphasis on what to do.

There are 4 basic ways water gets into your basement, 5 counting the condensation method mentioned above. Beginning with the least frequent, they are: Flooding, wall leaks (cracks and rod holes), sewer back-ups, and weep tile failure.

FLOODING

Look out your window. Do you see the Coast Guard coming down your street in a boat? Is that the CNN helicopter up there? Is the water pouring through your basement windows from the yard? If you can answer yes to all these questions, then it's a flood. Otherwise, it's not! If you tell your insurance company that your basement has FLOODED, you will get brushed off faster than a mosquito at a nude photo shoot! A flood is a large-scale natural disaster, also known as an Act of God, and as such is excluded from most insurance policies.

WALL LEAKS

These are a bit more common. New basements often develop cracks as the concrete shrinks, and if there is water sitting outside the wall, it will seep in through the crack. When the basement walls are formed, steel rods are installed so the forms don't bulge from the weight of the concrete. When the forms are taken off, the rods are removed, leaving hundreds of holes through the walls. The holes are supposed to be plugged by the builder, but they often miss a few, and these become leakers later on.

The best way to plug this kind of leak is from the outside. (Until recently it was considered the only way.) If it's not too far down the wall, you may want to try this as a do-it-yourself project. Dig down to expose the outside of the crack or hole, clean the surface for about a foot around it, smear on a heavy coat of mastic (asphaltic roof cement, for instance), protect that with a piece of heavy plastic sheeting or tarpaper, and put the dirt back in the hole. Not rocket science, but the difficulty of the job rises exponentially with the depth. (2 cusswords per minute at 1 foot, 4 at 2 feet, 64 at 6 feet...) The virtue of the method is that the pressure from the dirt and water against the wall actually strengthens your patch.

Inside patching is easier to do, but for obvious reasons is less reliable. For rod holes, there are patching cements available at the hardware store that do a reasonable job. One very popular brand is Dike Hydraulic Cement. Comes in a quart can, so you don't have to buy a 94 lb. bag for a few little holes. This stuff expands just a bit as it cures, locking it into the hole. Just be sure you clean the hole out as well as possible first. Look in the plumbing aisle of that hardware store for little round wire brushes used for cleaning inside pipe fittings.

Cracks are a lot harder to patch from inside. I have seen many attempts to do it with various kinds of cement, and most fail after a few months. The problem is that even if you don't have a structural problem, there is still a bit of motion going on at the crack. Seasonal swelling of the soil outside will do it. The fix therefore has to be something flexible. Urethane caulk patching and epoxy injection both work, but are very tricky to apply, and the methods are proprietary. In other words, you have to hire somebody.

SEWER BACK-UPS

If the water in your basement is coming out of the floor drains and smells bad, it's a sewer back-up. If your neighbors are having the same problem, then it's probably the city's pipe that's clogged, so the fix is up to them. If your basement is the only wet one, then the problem is likely in the sewer lead, the pipe that runs from your house to the city's pipe. The only cure here is to have the sewer cleaned out. "Snaking" with a steel auger is the normal method, and can work very well. Usually the problem is something insoluble that got flushed, but sometimes roots can get into the pipe. The contractor who does the snaking can usually tell what and where the problem is.

Caution: anything that gets wet in a sewer backup can be a real bacterial problem. If you can't sterilize it, throw it out!

WEEP TILE FAILURE

This is the biggie, the one that causes most trouble and expense. But what the heck is a weep tile? It's a pipe, but not in the normal water-tight sense. The weep tile system is a line of absorbent pipes that surrounds your basement, just below floor level, and collects water from the soil near the wall. The water is then delivered by means of more normal pipes, under the wall to a gathering point, either a sump for pumping or into the sewer system for drainage through a public sewer. The weep tile can become clogged over the years, and sometimes sloppy installation can make them perform poorly right from day 1. If this happens, they can handle little or no water flow. If the rain around the house accumulates faster than the weep tile can handle it, the water level out there gets higher than the floor elevation, and the water seeps in at the floor-wall joint. You have a leak. Remember, the floor-wall joint was never designed to hold back water. The weep tile system was supposed to keep it dry, so it wouldn't have to. That's why trying to seal this joint from the inside just won't work. Believe me, I've tried!

Solution? Of course, the best thing is dig up the weep tile and repair or replace it. This is traditional basement waterproofing. When the dirt is out and the wall exposed, it is normal to cover the wall with a mastic and maybe a protective cover over the mastic. This is what the salesman sells you on, but its the repair of weep tile that's really solving the problem. The drawbacks to this method are expense (around $85-100 per lineal foot of wall) and disruption of landscaping, pavement, deck, patio, etc.

Another solution involves digging up the floor the around the inside perimeter of the basement, and constructing a new weep tile system there. I won't go into the details of how and why this method can work, but it shouldn't be used if the wall has any other problems than leakage. (Cracking, bowing, etc. ) It costs about half as much as the old method described above, and is less disruptive.

Often the best way to deal with clogged up weep tiles is simply give them less to do. In other words, keep the gutters clean, keep extensions on the downspouts, and carefully maintain ground grading so it slopes away from the house. These precautions won't make your basement 100% waterproof, but they will probably solve most of the problem, at a small fraction of the cost of waterproofing. These are usually do-it-yourself projects, too.

One more thought on this whole scene. A basement is a hole in the ground, and sooner or later every hole in the ground gets water in it. This is as inevitable as gravity. Basements weren't intended to be finished and used as living area. If you chose to finish and use your basement this way, be aware that you are taking a risk of loss or damage to your posessions. No sealant, no system, no design feature can ever eliminate that risk entirely.

On that cheery note, I will sign off for this month. Next time, how about something lighter, like emergency preparedness!

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