April 1994 Edition

Cracked Foundation?

My house has a poured concrete foundation and the garage foundation was apparently poured separately. A crack has developed where these two foundations meet. Should I be concerned about this? Should I fill it?

Foundation cracks can be worrisome, but if you know how to read them, you can usually rest easier.

Dave McDonald, a structural engineer, said you are right. The two foundations were probably poured separately, and that it is very common for a crack to occur at the “construction joint” between them.

What you need to do is find out if the two foundations are actively moving apart. Paint a horizontal line across the crack and note its width and the date. Watch the crack over a period of months. If you find that the walls on either side are moving, contact a structural engineer.

If you find that the crack has stopped widening, fill in the crack with flexible butyl or silicone caulk. Since concrete expands and contracts, brittle patching compounds, such as mortar or concrete, are likely to fall out.

Basement Escape Windows?

I would like to move my son’s bedroom to the basement, but I’m afraid he would have no escape route in case of a fire. What can be done to make a basement bedroom safe?

You need to do two things to make a basement bedroom safe and legal. Install a smoke detector and make sure there is a door or window (in the bedroom) that can be used for escape in case of fire.

An escape window must have a clear opening of at least 20” wide and depending on your local building code, 22” to 24” high. The bottom of the window can be no more than 44” from the floor. Each bedroom must have it’s own escape route.

 To install an escape window, you will probably have to either deepen an existing window well and either build a retaining wall or slope the sides of the soil to permit the exit through the new window.        

Frankly, guaranteeing easy escape from a basement bedroom is often a headache. But it is worth every penny you spend to protect someone you love.

New Furnace Flue?

I want to install a new furnace in my house. The heating contractor says I need to have a new flue liner in my chimney. Is this true? Do I really need a new one?

Many people ask the same question when they go to replace a furnace. We have good news and bad news.

The bad news is that when you install a new higher efficiency furnace, you usually need a new flue liner-and it is expensive. A high-efficiency furnace produces cooler exhaust gas than your old furnace, so the old flue may be too large. If the flue is too large, moisture and chemicals can condense on the flue walls, eventually destroying them. A new liner controls this condensation, but costs several hundred dollars.

The good news, however, is that if you buy a furnace that’s even more efficient, you do not need a flue at all! A furnace that’s 90 percent efficient can be vented directly to the outdoors with PVC pipe. No flue liner is needed, not even a chimney.

You pay more up front, but besides not needing a new flue liner, you save on fuel. Here are some approximate costs: An 80 percent efficient furnace typically will save you about 22% on fuel, compared to older furnaces. A 90 percent efficient furnace will save you around 34% on fuel, but will cost about $600.00 more. For that $600.00, you save the cost of a new flue liner, plus you get an additional 12% savings on your fuel bills. Usually an excellent investment.

White Powder On Concrete?

We have a white crystalline substance growing on the concrete floor in our basement. What is this and how can we prevent it from forming?

What you see is “efflorescense”. It is a salt deposit formed when water travels through the concrete in the floor. As the water travels, it picks up soluble salts that are present in the concrete. When the water evaporates on the surface, the salts are left behind. These salt deposits can be cleaned up with a wet rag or mop.

Somehow water is getting under your floor. Check to make sure your yard is sloped away from the foundation and your gutters are clean and attached properly. If the downspouts are depositing the water right at the foundation, try adding drain pipes to divert the water away from the house. If you have a sump pump, make sure it’s working. If the staining occurs infrequently and in small amounts, it’s not a problem. If it’s more severe than that, it might be worth contacting a professional basement waterproofer.

Doors Will Not Latch?

On several doors in our house, the strike plate and latch no longer fit. The bolt is lower than the hole in the strike plate and the doors will not latch. How do I correct this?

Boy, we do not know of a homeowner who hasn’t faced this problem at least once. First, make sure that the hinges are tightly screwed in place. If they are, the door has either sagged or it was improperly installed. Sagging is more common with raised panel doors, less common with flush panel hollow core doors (the plain faced kind).

Now look at the gap between the top of the door and the frame. The gap at the top of the door is probably wider on the side of the door that has the latch. This usually means that the door has sagged slightly, causing the latch to miss the hole in the strike plate.

If the latch is missing the hole in the strike plate by less that 1/8”, the simplest fix is to file down the strike plate. It’s best to file a little at a time, testing the door latch as you go.

If the door latch is off by more that 1/8”, lower the strike plate. First remove the screws from the strike plate  and move the plate down to a position that will allow the latch to engage the hole in the strike plate. While holding the strike plate in the new position, mark the outline of the plate with a pencil. Use a small wood chisel to remove enough wood from the marked area so the strike plate will sit flush with the surface of the jamb. Fill the old screw holes with either wood filler or wooden matches. Screw the strike plate into the new position.

If you would like to fill the small gap created at the top of the strike plate, use a colored wood putty.

Sagging doors can also be an indication of movement in the

house structure. If this were the case, you would probably see cracked drywall or plaster.


It's time for the following maintenance on your home:

Clean out gutters and downspouts of fall leaves.

Open all crawl space vents.

Test all ground fault interrupters (G.F.C.I.) outlets and breakers.

Test all smoke detectors.

Check all fire extinguishers.

Change or clean furnace filters.

Check the water heater for any signs of leaks and test the temperature & pressure relief valve.

If you have a question, change of address, comment, home tip or would like to send Home Tips to your clients, send your letter to Home Tips, Christian Building Inspectors, Inc., 3697 Habersham Lane, Duluth, Georgia 30096. You can E-Mail your questions to us at rodharrison@christianbuildinginspectors.com. We reserve the right to edit questions for length.

Quote of the Month

“People can alter their lives by altering their attitudes.”

- William James

A Tip Of The Hat To:

Rob Owen

R.S. Owen & Company

Atlanta, Georgia

**** Thank You****