Fireplace Installation, Part 1: Digging
A couple weeks ago we ordered a fireplace for our living room. The catch going into this decision was the fact we lacked propane on our property. So we knew we'd have to get that handled first. Without it, the fireplace would be slightly less inviting.
So we visited the local Ag Supply and got hooked up with a 120-gallon tank. That's the smallest tank they'll fill onsite and we don't plan on running any other appliances (maybe a second fireplace in our bedroom if we replace the woodburning one up there now). A hundred and twenty gallons should easily last a season, if not multiple seasons.
The catch is they only plop the tank where we tell them, hook up the regulator, and run the line up to the house. Nothing else. Totally fine, except that also means since it'll be placed alongside the driveway away from the house, the line to the house is about thirty feet. Which requires digging.
So we dug.
The catch of this catch was a combo of the code requirements for placement of an outdoor propane tank (lots of minimum distances from things like our AC compressors and windows) and, because of those, the fact a sidewalk crossed the path of the intended line from the best location that met code. Ag Supply doesn't dig so we were on our own to figure out how to tunnel under a sidewalk.
In the end, it really wasn't hard at all.
After a few minutes on YouTube University, I had a plan. First, I had to dig a simple trench 18" below ground around the house. For that I used a combo drain spade and mattok. They worked like a charm.
Then it was time to trench under the sidewalk. The tank is going to sit where I currently have our winter tires stacked, just on the other side of the walk.
Like the guy on YouTube advised, I broke out our pressure washer. After picking up a 10' section of 3" ABS pipe, I cut it down to just longer than the width of the sidewalk. Then dug a long enough trench to the fit the pipe and the pressure washer nozzle. The extra length was good because it would give the water and debris I'd force out with the pressure washer room to drain.
The trick was on the house side of the sidewalk, the foundation for the garage stuck out about 12" underground. That's the bare minimum for a gas line to be buried so I had to hit that depth exactly, starting of course four feet further away on the downslope.
To help, I set a scrap 2x4 at the same 12" depth on the other side of the sidewalk. Then I just needed to get the angle of the slope right. If it was too high, I'd risk getting called out by the inspector. Too low, and I'd hit the foundation and likely not be able to actually pull the gas line through the pipe.
Feeling good about my methods, I got to work.
Surprising or not, it worked like a charm. Using the 2º nozzle on the pressure washer, I shoved it all the way up the pipe and ran it for about 10 seconds. Then let the sludge drain back into the trench behind me. Then tapped the pipe with a scrap of plywood and a sledgehammer. The water softened up the hardened dirt enough to allow the pipe to bore through. Rinse and repeat. In about ten minutes, we were all the way under the sidewalk.
Worth noting: before starting, I took a coping saw and cut a chamfer edge around the leading end of the pipe. The pipe is thick and I figured it could use some help boring through clay-ish, compacted dirt.
The temps here are supposed to drop tomorrow, down into the 20s. The Ag Supply guy is going to come out Tuesday morning to install the tank and drop the flexible gas line into the trench I dug. Then we get to figure out how to make the run from where his line ends into our house.
For that, I do have a plan… We'll see what obstacles we run into along the way.
