Garage 'ceiling height'

[QC Inspector]

My shop is framed with scissor trusses like that but it was designed that way and brought in as part of the truss package. You would be the first person I have ever heard of that wanted to convert to them in situ. An engineer would need to work out the sizes and fastening schedule as even an experienced carpenter would not likely know how. It would be a lot of work but you could do it without being noticed unlike raising the roof I suggested earlier. ;)

Pete

[Wood Grower]

Isn't something like this able to do the same job as a horizontal board? This is what I am thinking of doing building in place the remove the old system out after something like this is built. It seems with the right geometry something like this is fully capable of doing the same job as the horizontal board.

[cstephens2]

Well if it is possible then I am interested to figure this out. In theory I could build a new support beside old one and then take off each old one. I am not sure if my old books show this sort of thing or not. I guess I will have to study up on truss building. To me even if I could add new horizontal board but higher up than the wall top 2 or 3 extra feet would even be nice but having up to the top would be a dream I guess.

This isnt about truss building. Its about understanding the static and dynamic loads and how they transfer to your walls in your existing roof. .

[cstephens2]

The strength of the roof comes from its triangle shape, including the ceiling joists/rafter ties you are musing about removing. With those ceiling joists/rafter ties removed the weight of the roof will want to push the walls outwards. I highly doubt any inspector would approve what you are proposing, and I wouldnt want to chance a heavy snow load on that roof with the joists/rafter ties removed.

In the pic below, you see that the 'rafter tie/ceiling joist' is in *tension*, meaning that a stretching force is being applied to it. The strength of the rafter tie to resist the force of tension is what keeps the walls from being pushed out/bowed out. The more downward weight on the roof, like from a snow load, dramatically increases the tension force.

[Wood Grower]

This is a stick framed roof and you can't just remove all of the ceiling joists. They are what is keeping the ridge/roof in place. The joists could be removed if a beam was installed directly under the ridge, but this would involve a fair amount of work. Don't know the dimensions of the garage, but the beam may have to be substantial and supported properly at each end with posts, another beam over the door and possible upgrading of the foundation. The other option that has already been mentioned is to remove the roof and installed scissor trusses that would give you some vault. Yes, talk to the building official. There may be other issues not directly related to how it is constructed.

I could live with a beam but the support to the floor not so much. Unless can I make a timber frame inside beside walls to transfer the load to beside the walls instead of in the middle? That might be an option but also could be a pretty big pain......there are shelves built in to the sides there at least on the one side would probably be in the way but putting a timber frame in front of it and adding support to shelving might be an option I suppose. That would probably be way over the top option for a garage I don’t really want..... it is too small but I am trying to extent my stay in it a bit longer.....

[Wood Grower]

Any experienced carpenter should be able to open up the roof structure safely given enough wood to work with and maybe keeping one or two ties. The key here is experience, your questions don't inspire confidence in your knowledge to the point we should be encouraging you to DIY.
Rob

Well if it is possible then I am interested to figure this out. In theory I could build a new support beside old one and then take off each old one. I am not sure if my old books show this sort of thing or not. I guess I will have to study up on truss building. To me even if I could add new horizontal board but higher up than the wall top 2 or 3 extra feet would even be nice but having up to the top would be a dream I guess.

[Wood Grower]

I think that the roof could be jacked up and a couple three new courses of blocks added to get the needed height. That does hinge on whether the building is attached or free standing and being able to get matching siding.

This is a good idea but not possible.

[Wood Grower]

If collapsing is no concern, then disassemble it in an orderly fashion and rebuild it the way you want it that is done within building codes. Removing a pile of collapsed building is a daunting task. Is it a stand alone garage or part of a house. If it’s attached, that goes along way in determining your course of action. Sometimes, well actually all the time, collapsing takes down things that aren’t part of the plans. Like the concert blocks could be pushed outward. What is the actual height from floor to joists? 8’ is typical.

Detached and probably 7-8’. I didn’t measure but it too low. Probably I don’t need to touch part above overhead door because I open door and lost height again. But in reality could stay higher and be ok.

[iamtooler]

Any experienced carpenter should be able to open up the roof structure safely given enough wood to work with and maybe keeping one or two ties. The key here is experience, your questions don't inspire confidence in your knowledge to the point we should be encouraging you to DIY.
Rob

[bender]

Go gothic and install some flying buttresses on the side walls!

Seriously though, call up a structural engineer. They will tell you what can and can't be done.

[QC Inspector]

I think that the roof could be jacked up and a couple three new courses of blocks added to get the needed height. That does hinge on whether the building is attached or free standing and being able to get matching siding.

[Inspector Ron]

This is a stick framed roof and you can't just remove all of the ceiling joists. They are what is keeping the ridge/roof in place. The joists could be removed if a beam was installed directly under the ridge, but this would involve a fair amount of work. Don't know the dimensions of the garage, but the beam may have to be substantial and supported properly at each end with posts, another beam over the door and possible upgrading of the foundation. The other option that has already been mentioned is to remove the roof and installed scissor trusses that would give you some vault. Yes, talk to the building official. There may be other issues not directly related to how it is constructed.

[Mike in Waubaushene]

I kind of don’t care care if it collapses however there must be a way to rework the wood to have a vaulted ceiling and retain the strength? I don’t care if I need a forest to build it vaulted wood isn’t the concern. The concern is if it is possible to remove the horizontal wood and have the wood change angles to still support the overhead load.

If collapsing is no concern, then disassemble it in an orderly fashion and rebuild it the way you want it that is done within building codes. Removing a pile of collapsed building is a daunting task. Is it a stand alone garage or part of a house. If it’s attached, that goes along way in determining your course of action. Sometimes, well actually all the time, collapsing takes down things that aren’t part of the plans. Like the concert blocks could be pushed outward. What is the actual height from floor to joists? 8’ is typical.

[Wood Grower]

I would not want to be removing any of that roofing wood it it was mine, unless of course I didn't mind it collapsing, all of that wood is there for a reason.

I kind of don’t care care if it collapses however there must be a way to rework the wood to have a vaulted ceiling and retain the strength? I don’t care if I need a forest to build it vaulted wood isn’t the concern. The concern is if it is possible to remove the horizontal wood and have the wood change angles to still support the overhead load.

[bkrits]

I would not want to be removing any of that roofing wood it it was mine, unless of course I didn't mind it collapsing, all of that wood is there for a reason.