Main Floor Construction

We now have a completed foundation including the garage/shop area floor. It's nice to have a flat surface to work on for a change. From the near wall to the far wall is over 55 feet. When building a house, adding to the garage is inexpensive and if you're a car guy like I am you can use all the room in the garage you can get.

Now that the foundation is complete and all concrete work is done it's time to install the main floor joist system. The first order of business is the rim joist. With a Kuhns Brother's house the rim joist is extremely heavy duty. Most modern houses have a 2x10 or 2x12 rim joist but in our case the rim joist is 4x10 Hemlock. The Hemlock rim joists are installed by tow nailing them into the sill plate at about 12" intervals both inside and out. These timbers are heavy and should last for a couple hundred years.

Here you see the main floor support beam. Our plans called for a beam constructed of four 2x12's which are glued and nailed together to create a 12"x6"x40' support beam. I mentioned before that there will always be unforeseen problems that show up during construction. Well, in this case the plans called for 2x12's but someone at Kuhns Brothers made an error and sent 2x10's. This error cost us almost $300 since we had to purchase the correct dimension lumber locally. Mistakes happen and in the overall scheme of things this was a small inconvenience. We will keep the receipt and the company will reimburse us for the difference in cost when construction is completed.

It helps if you pre-position your floor joist material before you seriously get to work. In our case with a crew of only three, it was a necessity.

Actual installation of the floor joists is fairly easy. All you have to do is toe-nail them into the rim joist and sill plate. We used a nail gun for this task and trust me.... spend the money and get a good nail gun. The time saved is well worth it.

Between each joist a piece of blocking is installed. Not only is this required by our local code it ties the entire floor system together and keeps the joists straight and prevents them from moving.

This is the kitchen area of the house with the floor joists already installed. These are 18' 2x10's (all cut to fit the 17' span)

It pays to think ahead. Here you see the main hot and cold water lines pre-installed in the joists as they are put up. These lines will run from the hot water heater (at the far end of the house) all the way to the master bathroom at the other end of the house. If this house was being built on a basement installing them up in the joists like this wouldn't be necessary. However in this case there is no basement, only a "tall" crawl space. In order to keep the lines up away from any cold winter drafts the lines are installed out of the way. Both lines will be wrapped with two layers of foam insulation to protect them from freezing during extremely cold weather.

This is the main living area. Total span here is about 30 feet front to back.

Once all the floor joists are in place every other one gets a metal strap installed which helps to tie the joist to the outside rim joist.

Ready for inspection. Local codes require an inspection of the floor joists prior to sub floor installation. Total time to install the entire floor joist system was the better part of 5 days. That includes installation of the rim joist, construction of the main floor support beam, and installation of all floor joists.

That's all for this update. We passed inspection and started installation of the 3/4"x4'x8' tongue and grove OSB (oriented strand board) sub floor this morning.

Check back soon.