Reader Feedback: Issue 137, February/March 2001
Don’t backfill unbraced walls
I read with interest Robert M. Felton’s excellent article “Soil: The Other Half of the Foundation” in the December 2000/January 2001 issue (FHB #136, pp. 68-73). The article contained valuable information for builders and designers about a subject that is often misunderstood. However, when I came to the illustration on p. 73 showing the proper means to compact backfill near a basement wall, I shuddered. The information conveyed regarding clearances was sound, but the illustration showed an unbraced wall, with no first-floor framing attached, being fully backfilled. Basement walls are typically designed as simple beams, with support at the bottom and the top, and are not capable of resisting the lateral loads imposed by backfill until they are secured at the top by the first-floor framing. Backfilling basement walls without the framing or substantial bracing in place, especially when the walls are “green,” has resulted in many costly and potentially dangerous failures.
—Alicia F. McCormick, P. E. (structural engineer)
A use for those metal Altoids boxes
Jefferson Kolle makes a good point about disposal of razor-knife blades in his letter to the editor (FHB #136, p. 6). Medical offices have special disposal containers for “sharps” (needles and so on), but I’d never thought about the hazard of knife blades. However, I can imagine the eyebrows and voices of bosses all across the country rising fast at the suggestion of duct-taping individual blades as they wear out. I am adopting, and suggesting, a different approach: Altoids mints are sold in a metal container that makes a great place for used blades. And when it’s full, you can recycle the blades, container and all, in the metal recycling (wire it shut and write “knife blades” on it, for safety). Somewhere in your family or circle of friends, there is an Altoids addict looking for ways to use those empty metal containers.
—Bill Houghton, via e-mail
Don’t wire GFCIs in parallel
As with most articles in Fine Homebuilding, I enjoyed Rex Cauldwell’s “Ten Common Wiring Problems” in the December 2000/ January 2001 issue (FHB #136, pp. 114-119). However, an exception involving safety needs to be made for number 10, “Receptacles Wired in Series.” The suggestion to wire receptacles in parallel as opposed to in series is true except when a GFCI receptacle is involved. Parallel wiring of these devices will negate the benefits afforded to any downstream receptacles, posing a threat to safety when the GFCI is relied on for downstream protection.
One could argue that an experienced electrician would know to wire GFCIs in series; however, if this were always the case, then we would not be needing to read
Mr. Cauldwell’s advice based on his experience with common mistakes that he has encountered.
—Brad Hedrick, Doylestown, PA
I read Rex Cauldwell’s article “Ten Common Wiring Problems” (FHB #136, pp. 114-119), and I disagree with the statements in item number 10 with regards to “Receptacles in series” and “Receptacles in parallel.”
Both of the illustrated ways of wiring a receptacle result in a “parallel wiring.” The only difference is that in the method labeled as “in series,” the connection is made at the receptacle by two screws affixed to a metal connector. This metal connector bypasses the receptacle itself so that the current continues to flow to the following receptacles even if the first receptacle is defective. The only difference between the two wiring methods is therefore that one is made via wire nuts while the other is made through two screws and a metal tab. In both of these instances, a bad connection can develop if the nuts or screws are not properly tightened. Personally, I do not believe that a wire nut is that much more secure to warrant the extra work involved in running a pigtail.
To create true “series wiring,” you would have to run the hot supply wire to the “hot screw” on the first receptacle, a wire from the neutral side of the first receptacle to the “hot screw” of the second receptacle (and so on), while the neutral supply wire would go directly to the neutral side of the last receptacle in series (bypassing all others). Obviously, none of the receptacles would work unless something (i.e., an electric bulb) was plugged in and operating on each receptacle in order to close the loop. In addition, each of these receptacles would work then on a reduced voltage depending on the wattage (resistance) of each of the items plugged in.
A typical example of a “series wiring” is a decorative string of Christmas lights. This application of series wiring uses the voltage drop of a number of bulbs in a “series-wired” string to reduce the supply voltage (110v) to a safe, much lower voltage (i.e., 3v to 12v) without the need to have a transformer. However, if one of the bulbs in the string becomes defective, the electric loop is broken, and the whole string does not work. (Note: The newer varieties of Christmas lights use special bulbs with a built in shunting device to circumvent a total blackout).
—Werner Bonitz, via e-mail
Rex Cauldwell replies: Series and parallel are just the terms I use to distinguish these two methods of wiring receptacles. You’re free to call them what you want. But in any case, here’s how I define “series and parallel wiring” in this context.
1. I define a parallel receptacle circuit as one where you can remove the receptacle without losing any power downstream—it’s that simple. A series circuit is one in which if you do remove a receptacle, you lose power in all downstream loads.
2. If the wires are pushed into the holes in the receptacle back, a series hookup will have the sum of all the current of all the downstream loads going internally through the first receptacle. If you have ten loads downstream, screwed down or pushed in, all the current of those loads will be flowing through the first receptacle. This overheats the receptacle, by the way.
To shim or not to shim
Having read the article “Setting Prehung Doors” by Gary M. Katz (FHB #136, pp. 62-67), I find it is necessary to point out that the author and Fine Homebuilding are developing some new and dangerous trends here. Mr. Katz started installing hollow-core, prehung-door units without shims after he had taken a production trim contract at only $6 per door to install. He would have us accept that because his crew has installed countless doors using this method, without any stated problems, this should now be considered standard practice. Apparently, it is now permissible to use what were previously unacceptable shortcuts if we accept this work at unprofitable compensation. Furthermore, it seems that it is also possible to justify your methods, mediocre as they may be, by publishing “how to” articles and thereby establishing some level of credence and air of authority.
A piece of writing such as this would seem to be the antithesis of Fine Homebuilding. These methods will not result in “fine” work by any stretch of the imagination. I only hope that no beginning or apprentice carpenters adopt Mr. Katz’s methods. If they do, unfortunately, this will just be one more bad habit that I will need to untrain on my projects. For the record, the most basic and correct door-installation methods are:
• Doors, prehung or not, are installed plumb, not lined up with an out-of-plumb adjacent wall.
• Doors, hollow or solid, should be shimmed, three places on each side, with at least one shim behind the head jamb if it’s more than 3 ft. wide. If no shims were used, the jambs would be secured only by the very fragile connection with the thin edge of the casing.
• For all floor coverings, other than thick carpeting, the jambs must be scribed to fit the flooring.
—Jim “The Shim” Irvine, via e-mail
Gary M. Katz replies: As I said in my article, I have installed thousands of hollow-core prehung doors without shims, and I’ve never had a callback or settling problem with even one—no doubt because it isn’t the casing alone that secures the door. I shoot 21⁄4-in. nails through the jamb and the door stop into the trimmers (helps to secure the stop if the wind blows the door closed). And I replace at least one short hinge screw with a long screw that reaches through the jamb and secures the weight of the door into the trimmer.
Perhaps you haven’t had the experience of working a production job, where a carpenter’s knowledge, experience and innovation are challenged by the demands of both quality and quantity, but believe me, in case you were not there in the 1980s, earning over $250 a day installing prehungs was definitely not “unprofitable compensation.” And the margins on every one of those doors were almost perfect. Production methods are not always a sign of substandard work—look at the changes in framing, joisting and roofing used today by crews across the country. Many of these techniques were developed on housing tracts.
Also, you might be interested to know that one type of prehung door, sold by the bushel at big-box warehouse stores, is called a knockdown prehung. This type of unit comes with the casing attached to both sides of the jamb, though the jamb is in three pieces. The head jamb is slipped over the head of the opening, and then the legs are slipped over the trimmers and drywall. With the casing installed on both sides of the jamb, these frames are impossible to shim. In 1986, we installed more than 2,000 of these doors in one government-subsidized complex. State inspectors counted every nail and screw that we installed, but there was no requirement for using shims.
As for your other recommendations: Installing doors or trim perfectly plumb, though it may satisfy a finish carpenter’s need for perfection, is a disservice to the general contractor you work for and the homeowner to whom he is responsible. Many of the walls in the new homes in which I work (high-end custom houses) are up to 1⁄4 in. out of plumb; the walls in remodels often can be even more out of plumb. Installing a perfectly plumb door close beside a slightly out-of-plumb wall will only call attention to the error.
In the new homes in which I work, I am never asked to install the prehung doors after the wood floor is installed; the finish work is always installed and painted or stained before the floor coverings go in. But you are correct: On many remodeling jobs, hard-surface finished flooring has been installed before the doors and jambs, and then the jamb legs must be scribed to the floor.