# Cable installation with Open-web floor trusses



## treznik (Nov 12, 2017)

In my previous construction business we often used web trusses for clear spans to provide a more open concept living area. I'm not sure what your concerns are though. It's nice to not have to drill holes as in standard wood joists. We also followed the practice of running main cable routes to minimize wire congestion. Keeping in mind that plumbing and HVAC also use use the openings; on perpendicular runs we ran wire on the top of the bottom plate closer to the walls as possible and on parallel runs ran stapled the wires to the side of the trusses just above the bottom plate. As for the ICI cans the mounting brackets are the same as with standard joints. Occasionally we added some framing depending on the best positioning for the can. Sorry if I haven't been much help but if not maybe provide a little more detail on your concerns. You wouldn't use cable stackers on standard joists and they maybe too cumbersome to use on these trusses.


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## just the cowboy (Sep 4, 2013)

For the open truss I would pick the small triangle at an end and use that mount wires half way up, Stay away from middle openings due to other trades will want/need these. Research and watch where you drill on any of the factory engineered beams and trusses, one wrong drill spot can cost you big time.

Cowboy


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## treznik (Nov 12, 2017)

just the cowboy said:


> For the open truss I would pick the small triangle at an end and use that mount wires half way up, Stay away from middle openings due to other trades will want/need these. Research and watch where you drill on any of the factory engineered beams and trusses, one wrong drill spot can cost you big time.
> 
> Cowboy


Keeping the wire runs to just above the bottom plates provides the most unobtrusive way considering plumbing and HVAC requirements.


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## johnnygreenham (Aug 25, 2020)

Thanks guys for the reply. I guess my concerting was that running wires through any of the triangles, especially long distances, I'm sure I will get sag which may end up leaving my cables lying close if not resting on the sheetrock ceilings. I'll have at least 1-1/2" of distance from underbelly of the trust where they pass through the triangle but in-between the gap I wasn't sure if it was bad form not to secure the cables at intervals. Is it just deemed ok to have them lying in the bottom of the 'V' unsecured? 

Thanks for the tip about running my main raceways to the side of the build. Running perpendicular along the trusts I'll just staple them to the triangular bracing and wait for the plumber/heating guys to curse me out when I block his path! Only kidding, I always have there backs and will keep to the bottom


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## treznik (Nov 12, 2017)

johnnygreenham said:


> Thanks guys for the reply. I guess my concerting was that running wires through any of the triangles, especially long distances, I'm sure I will get sag which may end up leaving my cables lying close if not resting on the sheetrock ceilings. I'll have at least 1-1/2" of distance from underbelly of the trust where they pass through the triangle but in-between the gap I wasn't sure if it was bad form not to secure the cables at intervals. Is it just deemed ok to have them lying in the bottom of the 'V' unsecured?
> 
> Thanks for the tip about running my main raceways to the side of the build. Running perpendicular along the trusts I'll just staple them to the triangular bracing and wait for the plumber/heating guys to curse me out when I block his path! Only kidding, I always have there backs and will keep to the bottom


Most of the trusses we saw had metal bonding plates so running at the bottom of the V was not possible without causing damage to the NM. We stapled them every second joist just to prevent sagging. The extra time this took was more than offset by not having to drill holes. With today's electric wire staplers (e.g. Dwalt DCN701D1) this is much easier.


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## Easy (Oct 18, 2017)

I usually wait on the plumber and sheet metal guys to do their thing before I rout my cables. Otherwise you might just talk to them ahead of time so that you wont get in the way of their work. I would also consult with the carpenter before I drill any holes in the trusses of floor joist. I agree with Cowboy about the problems you can run into when drilling holes. I figured it might be good to post these 2 photos just to see if it helps anything but really it would be best to talk with the framers before drilling them. It is also an issue with post in walls that hold up ridge beams.


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## canbug (Dec 31, 2015)

If your worried about sagging, maybe screw in a 2x4 along the home runs that you could staple to? Just a thought and only a couple of dollars or there may be some laying around the site.
I have working in the open truss but we ran everything in pipe so that doesn't count.

Tim.


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## johnnygreenham (Aug 25, 2020)

Roger on all the above. Thanks all. Meeting with the GC and head plumber/heating guys tomorrow for a pow wow on site. They a good bunch and I've worked with them before so it shouldn't get too ugly . Let the fun begin!


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