Ceiling joists

Hi everyone. This is my first day visiting this forum and this is also my first post. I've been planning to build a studio in a free standing wood framed garage. I've been to many diy sites to learn framing and such. I've also been to many sites to learn about acoustics, isolation, etc. So, my plan is to build a room within a room in the garage. It will be about 23'X24' so I'll need a strong ceiling joist to span that distance. I've been looking at manufactured i-joists. The issue I have--all the diy sites don't really explain how to securly mount them to the top plate of a wall frame--which is what my application requires. Any ideas on this? Thanks in advance.

Spanning 23' is quite a distance! :shock: So that would imply that you are only going to have one single room for your studio? Is that correct? Also, 23 x 24 is very close to square, which is not too good for modal issues, and if your ceiling is going to be the standard 8 feet, then you have an even worse situation, as the length would be a multiple of the height. So maybe you could adjust one of the walls a bit, to avoid that modal response problem. Brien is the guy who can tell you about how to attach your joists to your framing. I think he's around, so hopefully he sees your thread. - Stuart -

Thanks for your response soundman2020. Actually, I'm planning to build two more semi isolated rooms within that large space. A control room and drum room with slightly lower ceilings. Both rooms will be in sort of a semi circle. The garage has 10' side walls so, yes, the main inner room will have 8' ceiling.

The manufactured i-joists are supposed to be engineered for longer spans--or so I read. I know my plan is probably less than ideal, but I'm dealing with budget restraints a well.

If I interpret what you are saying correctly, you have an existing room and you are going to install Ibeams on...the...what are they going to be installed on? I would hope it would be a newly framed interior wall assembly, even though at this point we are only guessing :)

Actually, I'm planning to build two more semi isolated rooms within that large space.

Then you only need to span those rooms! You need one inner-leaf ceiling for each room, and since the garage already has its own roof, you don't need to span anything there. So your maximum span is the width of each room, not the width of the entire garage. In other words if your control room is 10 feet wide, then you need to span ten feet for that, and of the drum room nest to it is 8 feet wide, then the ceiling joists of that only need to span 8 feet. Etc. Each room has its own individual ceiling, and they do not touch each other. So no, you do not need engineered beams. Just the right size joist for each room, most likely 2x8, or some such, depending on the span, the load, the deflection, and the type of wood. It would help if you could post your SketchUp model of the entire studio, so we can check it over and see if there might be ways to improve it, or at least so we understand it better! :) - Stuart -