Can my garage roof (truss system) hold a camper shell?

I used a series of rope and pulleys to lift the fiberglass top from my jeep.About 200 hundred pounds.The load was spread out over several trusses with two double 2x6 beams made to span the entire width of the garage and resting on the exterior walls,14 feet.They were installed via a small hole cut in one gable end of the building. No problems.I Know its slightly off topic, however the work shop where we store our alaskan popup camper we use two large laminated wood beams that span the entire width of the building. We use them to lift the camper on and off the truck via four one ton chain hoist, one at each jack bracket. No more wobbly camper jacks or swingout brackets for us.The point is with a little additional work bracing and supporting as you suggested you should be fine.It may be overkill but I believe in making things twice as strong as needed for safety. Ramp

The short answer is it depends. I don't think you will have any problems with hanging the shell from the ceiling. However, that assumption requires additional investigation. Trusses are designed to a certain capacity depending on the span, the dead load and the live load expected in the building. Dead load is all the items required to build the roof (sheathing, trusses drywall, mechanical systems conduit etc.)in other-wards all things installed at the time of construction. Live load are temporary loads like snow, people, boxes etc. it is a very specific number based on the planned use of the structure. This number is determined by the code used in your area. So any load that is placed on the trusses after construction that was not originally designed for will start eating into the live load. What I have seen happen is that people will start using the attic of their garage and think everything is OK becaouse the roof is not sagging. However, come winter and a large snowstorm and all of the sudden the garage roof is sitting on top of your car. Your camper could be the straw that broke the camel's back. Your post does not contain enough info to say that the roof can hold the shell. Only you can do that by evaluating the structure and how the garage attic and roof. So the closer the existing structure is to the as built condition the more likely it is that you will not have any problems. I am an Architect who worked as a code official for many years.

A lot of times people will put plywood up there and throw boxes etc for extra storage. When I spec a building and they plan to lift things like small engines they will sandwich 2 trusses together. 200 lbs is of no concern. Now its seems like humane nature to always want more. When you start adding more and you end up point loading 1000lbs or so you may want to rethink that. It would be easy to sister some framing and build up a truss or 2. If your 200lbs was of any concern we would see garages caving in all over the place.

My single door 2 car attached garage is 2x6 trusses spanning across the garage. Sheet rocked with rails & door opener. When constructed, a 2x4 was run in the attic fore & aft 90 degs to trusses. I attached another full length 2x4 with screws on top of the existing 2x4 and wrapped a chain around both, drilled a hole thru the sheetrock just big enough to drop a link thru, and shackled a small chain come-along to that.....I have been lifting my 8ft fibreglass Leer canopy off & on my truck for 5 years now without a quiver from the trusses.....

I design roofing systems for my projects, and you don't want to count on manufactured roof trusses to be able to carry any extra weight. I would add a pair of 2x10's parallel to the roof trusses that bear at the walls at each side. What I didn't see in your info was the span between walls. I can calculate what you would need to support your canopy if you can give me that information.

Reality Check wrote:

GMCPU53 wrote:
I worked for years in the retail and contractor home center business. The company I worked for also manufactured wood roof and floor trusses. These trusses were supplied for regular homes, commercial buildings, municipal buildings, large apartment complexes etc. Each truss is designed for an intended load with specified bracing points to make the truss system work as one unit. If a truss is not designed for a specific load to be hanging from it, then you are taking a real chance at a failure of the entire roof . When a roof truss has a load on it, ex: snow, the webs in those trusses push down against the bottom cord and then back up to the top to balance or absorb the load. Hanging something not planned for on the bottom chord could cause failure of the entire system because if the plates on one truss becomes comprised, it can affect all the trusses.

Joe

This is the sort of stuff that just kills me; everything GMCPU53 stated is technically correct. But the world isn't really black and white.

I think more often than not, folks don't read what the OP is really asking. I'm guilty of is; I missed the fact that the space was already sheet rocked.

The OP is asking about hanging a couple of hundred pounds off a truss system, spread out between four points. A system that can easily handle a 250 # man sitting in the rafters working on an HVAC or electrical system. He's not talking about lifting engines out of farm equipment.

Honestly, I think the 2x10's are overkill. They're just adding weight. One could use a 2x4 on edge and it would handle the partial weight easily.

Then again, I might need to re-think this and go ask my engineer if I can hang a garage door opener. I think the one I was looking at is 56#'s... about the same load the OP is asking about.

What "Reality Check" said! 200 lbs hanging from 4 Trusses as you described would be no problem. I would do it if I needed to.

I have my quite heavy fiberglass canopy from my longbed F350 hanging from my garage ceiling via pulley system similar to what you describe. I used 2 8 foot long 2x4's to support it. Been there for years. Ceiling is as straight and level as the day the house was built.

GMCPU53 wrote:
I worked for years in the retail and contractor home center business. The company I worked for also manufactured wood roof and floor trusses. These trusses were supplied for regular homes, commercial buildings, municipal buildings, large apartment complexes etc. Each truss is designed for an intended load with specified bracing points to make the truss system work as one unit. If a truss is not designed for a specific load to be hanging from it, then you are taking a real chance at a failure of the entire roof . When a roof truss has a load on it, ex: snow, the webs in those trusses push down against the bottom cord and then back up to the top to balance or absorb the load. Hanging something not planned for on the bottom chord could cause failure of the entire system because if the plates on one truss becomes comprised, it can affect all the trusses.

Joe

This is the sort of stuff that just kills me; everything GMCPU53 stated is technically correct. But the world isn't really black and white.

I think more often than not, folks don't read what the OP is really asking. I'm guilty of is; I missed the fact that the space was already sheet rocked.

The OP is asking about hanging a couple of hundred pounds off a truss system, spread out between four points. A system that can easily handle a 250 # man sitting in the rafters working on an HVAC or electrical system. He's not talking about lifting engines out of farm equipment.

Honestly, I think the 2x10's are overkill. They're just adding weight. One could use a 2x4 on edge and it would handle the partial weight easily.

Then again, I might need to re-think this and go ask my engineer if I can hang a garage door opener. I think the one I was looking at is 56#'s... about the same load the OP is asking about.

I worked for years in the retail and contractor home center business. The company I worked for also manufactured wood roof and floor trusses. These trusses were supplied for regular homes, commercial buildings, municipal buildings, large apartment complexes etc. Each truss is designed for an intended load with specified bracing points to make the truss system work as one unit. If a truss is not designed for a specific load to be hanging from it, then you are taking a real chance at a failure of the entire roof . When a roof truss has a load on it, ex: snow, the webs in those trusses push down against the bottom cord and then back up to the top to balance or absorb the load. Hanging something not planned for on the bottom chord could cause failure of the entire system because if the plates on one truss becomes comprised, it can affect all the trusses.

Joe

I've done it for years. No issues. If your roof system can't support an additional 200 pounds then you have some other issues to worry about besides your truck cap.