Trusses to support weight?

[Loresonde]

This is going to seem like a really weird idea but here goes...

We just finished up our garage, part of it is being used as a crossfit gym. We have gymnastic rings we want to get mounted to the finished vaulted ceiling about 2ft from the 13' peak. Trusses are 2x4s. Thinking about something mounted like this, tying 3 trusses together

2x10 mounted to the ceiling with (2) 4" lag screws per end
2x8 mounted to the 2x10 with (2) carriage bolts per end. 6" lag screws in the middle going through both boards into truss. The actual rings are mounted between the trusses through both the 2x8 and 2x10.

 

[rburke65]

And the question is......?

 

[wssix99]

You'd need an engineer or the truss manufacturer to confirm if they can take that point load.

If the trusses are 2x4's, the lag bolts alone (depending on their diameter) could be enough to dangerously weaken the truss.

 

[Loresonde]

Does it seem like it will be strong enough to support weight with swinging?
Should i tie 5 trusses to it instead of three?
Other ideas?
It'll be fine do it,...?

My concern would be about the vaulted trusses not being able to support the weight and bowing, trusses are 20'

 

[Loresonde]

You'd need an engineer or the truss manufacturer to confirm if they can take that point load.

If the trusses are 2x4's, the lag bolts alone (depending on their diameter) could be enough to dangerously weaken the truss.

1/4 or 5/16" ?

 

[shawhite]

Contact the truss manufacture and ask them

 

[laser3kw]

I see a typical single attachment point for each ring,such as a rope in an eye hook - correct?
no matter how many you tie together, the two closest to the point of attachment will see the greatest load.
Even if the the truss could hold up, the constant pounding of the attachment point would over time damage that area of the roof.
Myself, I would not do it.

 

[Loresonde]

I see a typical single attachment point for each ring,such as a rope in an eye hook - correct?
no matter how many you tie together, the two closest to the point of attachment will see the greatest load.
Even if the the truss could hold up, the constant pounding of the attachment point would over time damage that area of the roof.
Myself, I would not do it.

Attachment would be to both the 2x10 and 2x8, not directly into the truss, via 2 eye bolts.

 

[kd3pc]

not sure what you are using them for, just hanging, you may get away with it, but swinging from one to the other to the third and back will put added loads on the structure.

either size bolts through a 2x4 truss will weaken the overall integrity of the truss.

 

[bczygan]

Build it.

Then test it.

Hang double or triple the loads that it will experience (Sandbags).

To simulate shock loads, drop or swing these loads in the same way they will be used.

Do simultaneous shock loading if more than one person will use it at a time.

Rebuild or reinforce as needed.

That's how they design aircraft wings. You load it with sandbags until failure. You could do the same.

 

[wssix99]

Build it.

Then test it.

That's how Chernobyl happened.

That's how they design aircraft wings. You load it with sandbags until failure. You could do the same.

Wings are tested to confirm they are performing as designed. The problem here is that we don't know what the roof is designed for. It would probably **** for the OP of the roof collapsed during testing.

Does it seem like it will be strong enough to support weight with swinging?

Can you post a pic? You'll need the original truss engineer/company or an outside engineer (much more expensive) to confirm what it's designed to hold and what it can take. In most cases, these things are custom designed to your geographic location, codes, and house - so there is no way to look up the answer to this question.

I'd be really surprised if your roof can take this without having some kind of damage. (20' is a pretty good span.) A static load is one thing. (You could probably put a steel bar across multiple trusses to spread out that load.) Swinging is a totally different kind of thing. (I can say with some certainty that your trusses were not designed to support any moving loads at all. Tying trusses together may not solve this problem.)

Aside - My HVAC installer started to hang my new 600 lb. geothermal heat pump (attached at 4 points) from some very beefy 20' wood floor trusses. We called the truss company and were informed that the floor would collapse under the static load - never mind the vibrations. The unit is now sitting on an elevated pedestal.


Attaching stuff to trusses is a hard thing to do. Typically, they are engineered to have ceiling finishes screwed/nailed in to them. Putting bolt holes in can take out too much material, which is providing the strength to the system. This is illustrated by the reinforcing plates on the side that hold them together. Nothing goes through the material - it's jut all held together.

 

[Ironcrow]

I would not trust lag bolts for this. A porch swing maybe, but not the dynamic loads of gymnastic rings. I would spread the load with welded steel structure and bolt the ring hangers into steel.

 

[OccupantRJ]

I would go into attic and lay a 2x10 across about 5 or 6 trusses, then attach another to it underneath the ceiling, sandwiching the assembly to the lower members of the trusses. Add a few screws to prevent shifting. Additional collar ties could be added at a higher point to allow threaded rods to hang from them all the way through the lower assembly. If I was as scared of my trusses as some of you seem to be, I would move out. I have built 4 hoist rail systems hung from 4/12 and 5/12 pitch trusses in workshops over the years, one with 28 foot span. Some extra cross bracing and collar ties to tie trusses together and going up high to attach the load goes a long way as far as support capability.

 

[LB-1911]

I would go into attic and lay a 2x10 across about 5 or 6 trusses, then attach another to it underneath the ceiling, sandwiching the assembly to the lower members of the trusses. Add a few screws to prevent shifting.

Additional collar ties could be added at a higher point to allow threaded rods to hang from them all the way through the lower assembly.

If I was as scared of my trusses as some of you seem to be, I would move out.

I have built 4 hoist rail systems hung from 4/12 and 5/12 pitch trusses in workshops over the years, one with 28 foot span.

Some extra cross bracing and collar ties to tie trusses together and going up high to attach the load goes a long way as far as support capability.

You may want to refer to the original post

This is going to seem like a really weird idea but here goes...

We just finished up our garage, part of it is being used as a crossfit gym. We have gymnastic rings we want to get mounted to the finished vaulted ceiling about 2ft from the 13' peak. Trusses are 2x4s. Thinking about something mounted like this, tying 3 trusses together

2x10 mounted to the ceiling with (2) 4" lag screws per end
2x8 mounted to the 2x10 with (2) carriage bolts per end. 6" lag screws in the middle going through both boards into truss. The actual rings are mounted between the trusses through both the 2x8 and 2x10.

 

[laser3kw]

^^^^^^^^^^^^^
you caught that also?

 

[Loresonde]

That's how Chernobyl happened.




Wings are tested to confirm they are performing as designed. The problem here is that we don't know what the roof is designed for. It would probably **** for the OP of the roof collapsed during testing.




Can you post a pic? You'll need the original truss engineer/company or an outside engineer (much more expensive) to confirm what it's designed to hold and what it can take. In most cases, these things are custom designed to your geographic location, codes, and house - so there is no way to look up the answer to this question.

I'd be really surprised if your roof can take this without having some kind of damage. (20' is a pretty good span.) A static load is one thing. (You could probably put a steel bar across multiple trusses to spread out that load.) Swinging is a totally different kind of thing. (I can say with some certainty that your trusses were not designed to support any moving loads at all. Tying trusses together may not solve this problem.)

Aside - My HVAC installer started to hang my new 600 lb. geothermal heat pump (attached at 4 points) from some very beefy 20' wood floor trusses. We called the truss company and were informed that the floor would collapse under the static load - never mind the vibrations. The unit is now sitting on an elevated pedestal.


Attaching stuff to trusses is a hard thing to do. Typically, they are engineered to have ceiling finishes screwed/nailed in to them. Putting bolt holes in can take out too much material, which is providing the strength to the system. This is illustrated by the reinforcing plates on the side that hold them together. Nothing goes through the material - it's jut all held together.

This is all i've got, I'd have to search through our other pics to see if we have any better. Scissor trusses are under the gables at the top.

 

[Kevin54]

If you avoid the area in the bottom chord, where the 2x's are joined on the bottom chord, then like Occupant stated, take a 2x10 and span 4 or 5 trusses, you could probably get away with it. Is it acceptable....NO!!! Will it work....YES.

The only way that I know that it will work was that on my first garage a number of years back, I used my trusses to pull engines. I had 24' trusses that had the "W" web. I took (2) full size oak 2x8's that was 10' long. I sistered a 2x4 to the first and last truss in the 10' length so the oak 2x had a place to rest and was solid. The oak 2x8's were on each side of the web. I can't count how many big block engines we pulled using that setup. But there were 455 Buick engines, a few 454's, and mainly my nephews 440's that he was buying up for his drag racing days. Over the course of 5 or 6 years that we lived there, we were always pulling engines and there was never any pulling apart of the trusses. On a few occasions, the engines may have hung there for a couple of days. And just to add, a lot of them were pulled with the transmissions still attached.

It's was a little scary the first couple of times, but after a while, we never even thought of having any problems. And if you are still worried after sistering some boards along the trusses, if you are going to use it as a crossfit gym, if it is going to be set up as a gym and things not moved around to park a car in there on occasion, could you put a couple of post in to help support any added weight?

 

[Loresonde]

I would not trust lag bolts for this. A porch swing maybe, but not the dynamic loads of gymnastic rings. I would spread the load with welded steel structure and bolt the ring hangers into steel.

Free standing or attached to the ceiling somehow? Interested in hearing the ideas..i've got a tig and could fabricate something up.

 

[Loresonde]

If you avoid the area in the bottom chord, where the 2x's are joined on the bottom chord, then like Occupant stated, take a 2x10 and span 4 or 5 trusses, you could probably get away with it. Is it acceptable....NO!!! Will it work....YES.

The only way that I know that it will work was that on my first garage a number of years back, I used my trusses to pull engines. I had 24' trusses that had the "W" web. I took (2) full size oak 2x8's that was 10' long. I sistered a 2x4 to the first and last truss in the 10' length so the oak 2x had a place to rest and was solid. The oak 2x8's were on each side of the web. I can't count how many big block engines we pulled using that setup. But there were 455 Buick engines, a few 454's, and mainly my nephews 440's that he was buying up for his drag racing days. Over the course of 5 or 6 years that we lived there, we were always pulling engines and there was never any pulling apart of the trusses. On a few occasions, the engines may have hung there for a couple of days. And just to add, a lot of them were pulled with the transmissions still attached.

It's was a little scary the first couple of times, but after a while, we never even thought of having any problems. And if you are still worried after sistering some boards along the trusses, if you are going to use it as a crossfit gym, if it is going to be set up as a gym and things not moved around to park a car in there on occasion, could you put a couple of post in to help support any added weight?

I've thought about putting a brace of some sort from ceiling to floor near the mounting for the rings, problem is is limits use of the whole side of the area. Trying to find a solution that is up in the ceiling.


I could run a 2x10 across the 12' length on the drywall side perpendicular to the trusses using some 3.5" wood screws to tie all the trusses together and mount the actual rings to a separate 2x10 and 2x8 sistered together and lag screwed into 3 trusses...mounting the rings to the sistered boards not the trusses.

Thinking through some ideas, appreciate all the comments so far, dont want to put these up and get to doing muscle-ups and have a 40# board come crashing down on me or worse.

 

[bczygan]

I've thought about putting a brace of some sort from ceiling to floor near the mounting for the rings, problem is is limits use of the whole side of the area. Trying to find a solution that is up in the ceiling.


I could run a 2x10 across the 12' length on the drywall side perpendicular to the trusses using some 3.5" wood screws to tie all the trusses together and mount the actual rings to a separate 2x10 and 2x8 sistered together and lag screwed into 3 trusses...mounting the rings to the sistered boards not the trusses.

Thinking through some ideas, appreciate all the comments so far, dont want to put these up and get to doing muscle-ups and have a 40# board come crashing down on me or worse.

How about temporary braces on each side of where the rings are mounted?

Set them in place when using the rings and remove when finished.

Then you are effectively using just a short portion of the truss for support. This will make it much more adequate. I would still connect it to a number of other trusses in both directions, to account for lateral loads. And don't screw it together, bolt it.