Sunroom Part 3 Floor Trusses or How to Replace a Floor Joist Adventures in Remodeling

Sunroom Part 3  Floor Trusses or How to Replace a Floor Joist Adventures in Remodeling

Sunroom Part 3 Floor Trusses or How to Replace a Floor Joist

Now that we have most (not all) of the foundation issues resolved,its time to start building something!

This is a long post because I wanted to show just how easy it is to replace those rotted out floor joists.

Materials arrive for the build. I specified open web trusses for the floor. You have three common choices for a wood floor system dimensional lumber like 2X10 floor joists, I joists which is a strandboard panel capped by 2X lumber on edge or the open web truss pictured. I selected these because I want to run all of the HVAC pipes and other mechanicals through the truss, not under, so that I have maximum space in the crawl area.

Heres the start of setting the trusses. I used a carpentry crew for the rough build. I built the mudroom by myself and it took about two months too much time to be without a roof on this structure. These guys will be here for a week and get it under roof.

The trusses are in place and the Solid Start rim boards are attached. Engineered rim boards were used because I had custom trusses made to a specific height to match the existing floor levels. This was to keep the sunrooms floor on the same plane as the existing floor. Youll see why thats important (at least to me) in a latter post.

Were finally going jackless! The front foundation was framed and the pour is underway.

Final pour for the front foundation is in. No more concrete trucks for now.

Now we can turn our attention to those rotten and termite eaten floor joists. Ive replaced 20 or so of these, so I did develop a system that seemed to work for me. You see in the above photo that the existing floor joists dont line up with the new floor trusses. This is a bad thing, and a good thing. Bad because they dont line up good, because we have to replace them anyway.

To remove the joist just cut it 3/4 the way up towards the top of the floor joist from below. I will say that you dont need to jack up the floor unless its on the exterior wall, but you must do one at a time from start to finish. If you do have excessive sagging a temporary support wall will do the trick.

Then get a small sledge and beat the crap out of it. Split the bottom off and continue to pound away. The red chalk lines you see in the picture is where the new joist will go.

Once you get to this stage you can pry the remaining wood away from the flooring nails.

Take your trusty angle grinder and grind them off flush to the floor. In this step its important that you take care not to burn your house down.

Use some PL glue in the proper place and get ready to beat the wood a little more.

Since I install these by myself its good to have a clamp on one end to apply pressure this way when youre working on the other end it wont bounce out of position. Here the clamp is putting pressure to the new floor joist. You just work it by hammering the joist until it is upright.

This is how the floor trusses are tied to the new floor joists. They are both sitting on the new poured wall foundation. The old floor level will have a 1/2 plywood overlay before the hardwood floors are installed. The trusses will only have a 3/4 subfloor and the hardwood will be applied over that. This will give a seamless floor transition from the kitchen into the sunroom. Once the floor joists are in place I fasten construction screws through the floor into the joist  from the top every 4-6 the length of the joists.

So well just keep moving along. Stay with me one day Ill get to paint something.

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