We set our last heavy duty 18″ tall open web floor truss this morning and definitely are delighted to be through that chore. Normally, we use the 12″ TJIs, which are basically wood I beams made out of chip board. They are extremely light and easy to work with.
In this case, passing extremely heavy floor trusses up 9′ to somebody sitting on an 8′ ladder was not going to happen on my watch. So, we set up scaffolding bucks in the corners and half way down the house and ran telescoping scaffolding in between them.
Besides being a lot safer, I don’t think we really lost any time, as it takes but a second to set up scaffolding when you don’t actually have to level it (we are working on a level floor after all). I would argue that the time it took to set up the six sections of scaffolding is about the same as if we had to be constantly working from and moving ladders. We went ahead and set up the scaffolding right after raising the exterior walls and used the scaffolding to easily cap plate and string line the walls before setting all the trusses too.
Most people go with these open web floor trusses because you’re able to leave an open box going the entire length of the house and run your main hvac trunk in there such that you don’t have to drop the ceiling with a soffitt. Because our hvac load is so small on this house, we are actually going with mini splits, so you could say it’s a waist of money as the TJIs are definitely cheaper.
However, one benefit of the truss system is that we are able to clear span 24′ and don’t need to need to have any interior beams for support. This allows us to keep a fairly open floor plan, or allows one to make changes later on without any structural ramifications.
The open webs will come in handy for us too, as we do have a fair amount of smaller 4″ duct work for our ERV system and it will make it really easy for running all our plumbing. One interesting thing I plan on doing is keeping all the plumbing and wiring to the top 12″ of the truss and then wrapping the bottom 8″ or so of the trusses to basically make them look like old beams. Besides being a cool look, it will give us the sense of more ceiling height too.