Noises in Floor System
Noises in Floor System
(OP)
At one of the residential homes I designed, TJI floor joists were installed with top flange hangers welded to a steel beam (no nailer used). All components are in accordance with the manufacturers recommendations, but we still have nasty noises, like metal on metal (it is not because of shiners).
Any ideas about what causes this and how to fix it would be greatly appreciated.
Any ideas about what causes this and how to fix it would be greatly appreciated.






RE: Noises in Floor System
Also is possible to get a bit more of an idea of the type of noise, squeak, banging ect???
When in doubt, just take the next small step.
RE: Noises in Floor System
This process is exacerbated by hard floor finishes such as tile. Most building codes in the US limit the sound transmission in wall-to-wall and floor-to-ceiling conditions. The construction method you described does little to mitigate such sound transmission.
You will need to either insulate the sound or isolate the sound. Insulation methods are obvious...batt, sprayed, or foamed. Isolation is a little less obvious. Rubber washers between the hangers and the beam would be one method of isolation...not great, but workable and provides some sound transmission reduction. Another is to coat all the hangers with a resilient coating (rubberized, urethane, etc.).
Filling the cavity with insulation will help. Placing a sound isolation membrane on the floor above will help also.
RE: Noises in Floor System
RE: Noises in Floor System
Firstly, although I think I have heard the term, I can't remember. What is a "shiner"?
Are you certain that the noise is from the joist to beam connections? If so, the information requested above by rowingengineer would help us to speculate. What time of day are the noises noticed? At what frequency?
RE: Noises in Floor System
A "shiner" is when you have a nail showing above the plywood, that is slipping causing squeaking.
It got the term from reflecting or shining due to wear from traffic from protruding above the surface of the plywood sheathing.
This is not the Australian version of a black eye...
Confusing enough?
Mike McCann
MMC Engineering
RE: Noises in Floor System
RE: Noises in Floor System
That's why its a good idea to both nail and glue floor sheathing in place.
RE: Noises in Floor System
Mike McCann
MMC Engineering
RE: Noises in Floor System
rowingengineer: a TJI is a member looking like an I-beam, but made of recycled/engineered wood
The noises definitely occur at the connection between the TJIs and the steel beam, and they occur when somebody walks on the floor adjacent to the steel beam.
The building is still under construction, i.e. the framing is finished but still exposed, with no finishing work done so far. I.e., we can exclude any noise transfer from hardwood floors, tiles, etc.
The 2 main scenarios we are looking at right now are lackluster welding (which of course the manucfaturer denies) or the TJIs moving at the hanger due to inappropriate nailing, lack of adhesive, lack of web stiffeners, or any given combination of the above.
And of course our main problem is finding a way to fix it.
Thanks for your input.
RE: Noises in Floor System
Mike McCann
MMC Engineering
RE: Noises in Floor System
Have you looked closely at connections from the bottom side when someone walks over the connections?
A link to the manufacturer's recommendations which were followed would help.
RE: Noises in Floor System
This is one reason why I always use a nailer (3X) on the top of any steel beam when I use top mounted hangers. As Ron said, it is a sound transmission break. I always glue and screw, if possible.
Mike McCann
MMC Engineering
RE: Noises in Floor System
no, they did not intsall blockings to fill the hangers. The bottom of the hangers does not touch the steel beam, but the wood does. The system is shown in the Simpson catalog 2009 on page 69 (with lumber joists, where we used TJIs). We used LBV hangers
Mike:
sounds logical to me, we will try to interrupt the sound transmission somehow in the next couple of days.
And yes, sounds like a good idea not to use welded hangers anymore in the future and go with a nailer instead.
RE: Noises in Floor System
RE: Noises in Floor System
actually, there are TJIs on both sides of the steel beam, with equal spans, so rotation is not an issue. There is also a load bearing wall on top of the beam, supporting another floor, thus further restricting any rotation.
RE: Noises in Floor System
Is there a way, using power actuated fasteners, to anchor the wall/floor diaphragm to the beam by shooting through the wall plate into the steel beam flange? This might dampen the effect...some? Will not eliminate it though.
Mike McCann
MMC Engineering
RE: Noises in Floor System
RE: Noises in Floor System
RE: Noises in Floor System
The noises are gone.
Thanks for all your input
RE: Noises in Floor System