Safe Installation of Basement Water Heaters

In the article “Condensing Storage Water Heaters” (6/09), it appears that the gas-fired unit is located in a basement, but there is no mention made of safety issues here. A plumber told me that he would never, ever put a propane appliance in a basement due to the risk of leakage and explosion. Any additional thoughts?

Kris Calvin

Earthwood Timber Frame Homes

Sisters, Ore.

Author Jim Lunt responds: The heater is in a basement, but it uses natural gas, not propane. There are no special venting requirements for a natural-gas appliance as long as the area in which it is located has venting to the outside, which this basement does. If you install a propane appliance, you must be concerned about proper venting. Propane is heavier than air, so it settles to the floor. Therefore, the room must have an exterior vent at its lowest level. If the basement is below grade, there must be a floor drain that vents to the exterior by gravity, and the line must be sloped like any drain line so the propane can flow to the exterior.


Galvanized Pipe Okay for Gas?

I noticed in Jim Lunt’s article that the water-heater gas line was being connected using what appears to be galvanized pipe. Here in the Midwest, I’ve always been told that “black pipe” should be used for this application.

Jonathan Klausler

Berwyn, Ill.

Author Jim Lunt responds: The pipe you see is the existing galvanized pipe supplying gas to the heater. Galvanized pipe is code-approved for gas in the UPC (1209.5.2). Typically, we will use black iron pipe inside the building, but in this case, we simply tied into the existing line.


Painting Old Porch Floors

I was happy to see the article about making old porch floorboards last (On the Job, 6/09) and have a couple of comments. The author suggested using a “high-quality exterior primer” on floorboards, but I’ve seen that method fail on dozens of porches over the years. Porch deck enamel often does not stick well to regular exterior primer. Also, white primer, shown in the article, should not be used under a colored top coat because it sticks out like a sore thumb whenever the top coat wears away.

The directions on porch enamels say to use the same porch enamel as a primer, either thinned or full strength. To slow rot and avoid cupping, all four sides of the boards should be painted before installation. After installation, another coat or two of porch enamel should be used. Given the beating porches take from sun and rain, the client should count on repainting every few years.

Dan Miller

Elgin, Ill.

Author Tom O’Brien responds: In retrospect, I should have devoted more than half a sentence to the complicated subject of priming and painting. Mr. Miller is correct to point out that many floorboard paints are self-priming. I like these paints for new floors, but when I’m restoring an existing floor — replacing rotten boards and blending them in with the old ones — I prefer to use an epoxy-reinforced floor paint that’s intended to be applied over previously painted or primed surfaces. At the point in the article where I casually mentioned applying a “high-quality exterior primer” to the floorboards, I should have stressed the importance of choosing the right primer. If you don’t use one that’s suitable for floorboards and compatible with the finish paint, you could have a paint failure such as Mr. Miller describes.


Corrections

In “Reroofing with Asphalt Shingles” (7/09), CertainTeed Corp. should have been listed as a manufacturer of fiberglass-based shingles, not organic-based.

And in “Innovative Products 2009” — also in July — the price of Interwrap’s Titanium UDL-30 underlayment was misstated as around $140 per square. In fact, the cost is around $140 per 10-square roll. — The Editors