Sunday, December 20, 2009

Building Drain

The building drain is the lowest point of a home's plumbing system. It's where all of the other drains (sinks, showers, toilets, etc.) meet up. I've installed a back-water valve (aka back-flow preventer valve) in the building drain at the point just before the drain exits the basement underneath the footings.

If for some reason the septic tank ever gets full, the back-water valve will prevent any nasty stuff from coming back up the building drain and into the house.

When I pour the basement slab, the back-water valve will be left accessible for maintenance.

Friday, December 18, 2009

Rough Plumbing Work

I'm spending a bit of time on the Drain/Waste/Vent system again. I have to run some of the vent pipes up the exterior walls, so I have to cut some wide slots in the styrofoam.

There are hot-knife tools that are made specifically for cutting styrofoam, and I've also heard of people using electric chainsaws to cut away the foam. I don't really have that much to cut, so I can't really justify buying either a hot-knife or an electric chainsaw.

I've improvised by using my reciprocating saw with a very short blade. I make a couple of passes down each side of the slot, and then I use the claw end of hammer to hack out the foam. It does make a bit of a mess (that's where the hot-knife is better), but it works just fine.

For the tight spots where I have to take the foam out behind a floor joist... I just put a 12" blade in the reciprocating saw and make the cuts at a really shallow angle up behind the joist. Then I just poke away at the foam with a long screwdriver until it all comes out.

Tuesday, December 15, 2009

Rough Wiring and Half-Sistered Joists

Lately I've been trying to get some of the rough wiring done, but this is another one of those jobs where I can't do the main task-at-hand until I finish another seemingly non-related task.

I'm planning on putting ceramic or porcelain tile throughout the house. One of the prerequisites for laying tile is a strong, stiff floor. If the floor flexes, the grout between the tiles can crack. In order to help stiffen the floor, I'm reinforcing all the floor joists by screwing and gluing a 12" wide piece of 1/2" plywood to one side of each joist. (When renovating existing homes, sagging floors are often fixed by installing new joists directly beside existing joists. That's called "sistering the joists".)

Since a lot of the wiring will run through the floor joists, I need to get the joist reinforcement done before I can run any wiring. Once the joist reinforcement is done, I'm able to drill some holes and run my wire through the joists.