Plastic Piping Can Be Grounded for Safety

Question: We recently had some plumbing repairs done by a local handyman. He installed some plastic pipe in our domestic water supply system. A neighbor looked at the job and said the repair compromised the main ground connection in our home’s electrical system. Do we have a problem? If so, how can we correct it?

Answer: Most electrical codes require a home’s electrical system to be grounded through the copper or galvanized-iron water supply pipes that lead from the water main to your faucets. This is done by clamping the ground wire from the panel to a pipe. A problem can arise, however, when this continuous ground is disrupted by splicing a length of plastic pipe in the water system.

Though not allowed by code in most areas, plastic water piping has enormous appeal to those uncomfortable with traditional piping materials and methods. If a part of your home’s water supply piping has been replaced with plastic, you can still have the protection provided by a proper and legal ground.

To reestablish the ground, simply fasten approved grounding clamps to the metal piping on each side of the plastic splice. Then span the gap with a short length of No. 4 solid ground wire. Bind the wire tightly in the clamps and the job is complete.

Water Feels Different After Tank Is Replaced

Q: Our hot-water storage tank recently leaked and was replaced by another stone-lined tank. My family and I noticed a change in the feel and texture of the water in the shower and sinks the evening of the installation. My wife describes the water as feeling slimy or soft. I thought it felt silkier, similar to diluted mineral oil or water that had cement residue mixed in with it. Nevertheless, the water was nice and hot.

What can you tell us about stone-lined hot-water storage tanks? Will the residue rinse away with time and is it a health hazard?

A: The term “stone-lined” is really a misnomer. The storage tank is actually lined with concrete. Probably, the company that manufactured your unit uses a fine sand in the concrete mix, which has the texture of flour.

You were on the right track when you said the water had a cement residue feel to it. Any tank residue should flush out shortly. If it doesn’t, contact the manufacturer.

There is nothing inherently unsafe about stone-lined hot-water tanks, but if you are concerned, you can have the water tested to see if its mineral content exceeds the Environmental Protection Agency standard for potable water.

Crawl Space Covering Prevents Pests, Rot

Q: The sandy soil of the crawl space below my house is usually moist and downright wet during the rainy season. When a termite exterminator was treating my house, he placed a plastic sheet over most of the space but not all of it. Is this adequate?

A: The sandy floor of the crawl space should be covered with a vapor barrier of polyethylene plastic sheet, 4 to 6 milliliters thick. This reduces moisture in the space, and the potential for rot in wood framing. Dry conditions also reduce termite and carpenter ant activity.

The vapor barrier must cover the entire floor, and joints between sheets should be taped closed with heavy-duty plastic tape. The vapor barrier should extend to the foundation wall and be taped to it.

Reduce crawl space moisture by ensuring gutters and downspouts discharge water away from the house and that the ground slopes away from the house on all sides.

Further, there should be at least two vents--one each at opposite sides of the foundation. The vents are sized as follows: 1 square foot of unobstructed vent area for each 1,500 square feet of crawl space.

To submit a question, write to Popular Mechanics, Reader Service Bureau, 224 W. 57th St., New York, NY 10019.