I have occasion to work at a Catholic retreat center in the beautiful north Georgia mountains, adjacent to a National Forest. Over the Christmas break, in a bitter cold spell, one of the mobile homes used as temporary housing had frozen water lines (no one was at the camp to "drip" the water). We got the lines thawed by covering the suspect freeze points with plastic sheeting and using a "torpedo" heater (see Anna Satler's excellent post on using a hair dryer; unfortunately for us, the number of frozen pipes we had would have required 10 or 12 hair dryers and maybe half the power of the community!) to take care of business; it was a hassle but the situation was resolved with no need to replace broken water lines and shower drains. Our next immediate need was to insulate the area under the home, then skirt it to protect the insulating board. Keep reading, even if you don't own a double wide; this fix can be used for any structure that is raised above the ground -- a mountain cabin, wood shop, or any building which has water lines to protect.
The gallery illustrates the basic process; join me after the jump.
"pink board", a local (or maybe not) generic term. We used a 4' x 8', light-weight insulating board that comes in thicknesses starting at 1/2" (R3
. ) Measure the average height from the ground to the bottom of your elevated structure and multiply that number by the total length of the sides; divide that
amount by 32 to get the number of 4' x 8' sheets and then add 10% for cutting waste. This stuff is light as a feather and child's play to handle, unlike some of the other material I've talked about -- backer board
and sheet rock
- 2 x 4 x 8' pressure-treated (p/t) lumber -- enough lineal footage to go around the perimeter, plus (you guessed it) 10%.
- three p/t stakes for each 2 x 4 you bought; get extra 2 x 4's and cut them into 2' lengths with sharpened ends; you can get 4 stakes from each 2 x4. If you don't want to do the math, get your 5th grader to do it and see how smart s(he) is. (Hmm ...that could be a television program; I think I'll look into that.)
- circular saw.
- knife to cut the pink board -- you may use your ginsu on this project.
- hammer; nails and a nail gun or screws ( we used sheet rock screws) and a screw gun; you'll need about 6 for each 2 x 4.
- tape measure.
- carpenters pencil.
- sledge hammer, for the stakes.
- plumb line.
- button nails -- roofing nails with a collar on them; normally used for roofing so they don't punch through the felt or, in this instance, the pink board. You can see them in pic #6 in the gallery.
- panel siding -- the same measurements as for the insulating board; we used HardiPanel.
Safety: as usual, is paramount -- eye and hearing protection, gloves, stable work surface; utilities marked if necessary.
Time: it took 3 men two days to do the job.
lay out the 2 x 4's around the perimeter such that, if you drop a plumb line, the outside edge of the wood is just inside the frame of the structure.
drive stakes, on the inside of the 2 x 4, at the middles and ends, joining the butt ends and fastening them together; do this completely around your structure.
here's the easy part -- using the button nails, fasten the pink board to the inside of the frame of the structure and the inside of the perimeter 2 x 4's, cutting the insulating board to follow the contour of the ground in order to minimize air infiltration and allow heat loss; see photo 5.
now, here's the hard part -- on the outside of the 2 x 4's, fasten the protective paneling, sliding the top edge of the panels up inside the drip edge of the structure, again cutting the bottom of the panel to conform to the ground. (See photo 10.) At some convenient location, cut an access point to the crawl space, frame it, and install some sort of a closing device (e.g. hasp, slide bolt, etc.)
That's it -- you're finished. The end result, on this structure at least, is that there have been no subsequent freeze ups, even without supplementary heat. The temperature inside the crawl space is about 20 degrees warmer than ambient and the heating requirements for the building are markedly reduced. Needless to say, if it gets REALLY cold, the occupants drip the water.
Go to it!