Joining wall to ceiling

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OpIvy
Posts: 11
Joined: Wed Oct 14, 2020 7:47 am
Location: North Qld, Australia

Joining wall to ceiling

Post by OpIvy »

This is another ‘studio in the garage build’….
There’s a smaller 3-walled part of the garage I’m planning on using and need to build a 3.5m wall to separate this room from the rest of the garage.
This wall will be double stud but my question is how should this wall meet the ceiling.
There’s no ceiling atm- only exposed joists with timber flooring on top for the upstairs living room. So I was going to use resilient clips/ hat channel, insulation and two layers of plasterboard. The ceiling will extend about 400mm further out from the new wall.

So when I build the wall, do I just build the framing up to just under finished ceiling height and then leave a small gap between the ceiling plasterboard and wall plasterboard, fill with backing rod and acoustic sealant?
Similarly, where this wall meets the other existing wall, which I will convert to staggered stud….. do I just leave a small gap at the corner to decouple it and then seal?
This bit is a little confusing because if I bolt the framing of the new wall to the concrete floor, how do I ensure it stays solid upright if it’s not directly fixing to the ceiling or other wall.
I hope this is clear……
Thanks for any advice.
Paulus87
Senior Member
Posts: 652
Joined: Sun Mar 02, 2014 8:42 am
Location: Wales, UK

Re: Joining wall to ceiling

Post by Paulus87 »

OpIvy wrote:This is another ‘studio in the garage build’….
There’s a smaller 3-walled part of the garage I’m planning on using and need to build a 3.5m wall to separate this room from the rest of the garage.
This wall will be double stud but my question is how should this wall meet the ceiling.
There’s no ceiling atm- only exposed joists with timber flooring on top for the upstairs living room. So I was going to use resilient clips/ hat channel, insulation and two layers of plasterboard. The ceiling will extend about 400mm further out from the new wall.

So when I build the wall, do I just build the framing up to just under finished ceiling height and then leave a small gap between the ceiling plasterboard and wall plasterboard, fill with backing rod and acoustic sealant?
Similarly, where this wall meets the other existing wall, which I will convert to staggered stud….. do I just leave a small gap at the corner to decouple it and then seal?
This bit is a little confusing because if I bolt the framing of the new wall to the concrete floor, how do I ensure it stays solid upright if it’s not directly fixing to the ceiling or other wall.
I hope this is clear……
Thanks for any advice.
Hi,

Please fill in the rest of your profile so we know where you're from, and then please draw up a plan of your space and what you're proposing.

Paul
Paul
OpIvy
Posts: 11
Joined: Wed Oct 14, 2020 7:47 am
Location: North Qld, Australia

Re: Joining wall to ceiling

Post by OpIvy »

No worries.
I've attached a rudimentary sketch of what I'm working with. There's not a lot of detail because I haven't made final decisions yet except for the ceiling, which I explained in above post.
The corners of the new wall (circled red) is where I'm confused. I'm trying to decouple from existing walls as much as possible but not sure how to fix the double stud wall to the rest of the structure.
That internal wall at the bottom will probably be a staggered stud wall due to space so it will be partially decoupled from the existing wall. So does that mean I should just screw the double stud wall straight into the outside of the staggered studs at the corner?
Needs to be held upright by something and the it can't be at the ceiling.
Paulus87
Senior Member
Posts: 652
Joined: Sun Mar 02, 2014 8:42 am
Location: Wales, UK

Re: Joining wall to ceiling

Post by Paulus87 »

OpIvy wrote:No worries.
I've attached a rudimentary sketch of what I'm working with. There's not a lot of detail because I haven't made final decisions yet except for the ceiling, which I explained in above post.
The corners of the new wall (circled red) is where I'm confused. I'm trying to decouple from existing walls as much as possible but not sure how to fix the double stud wall to the rest of the structure.
That internal wall at the bottom will probably be a staggered stud wall due to space so it will be partially decoupled from the existing wall. So does that mean I should just screw the double stud wall straight into the outside of the staggered studs at the corner?
Needs to be held upright by something and the it can't be at the ceiling.
Ok cool,

So stud wall next to the other room - does it have plasterboard on both sides of the studs?

If it does, then what you need to do is take the plasterboard off of that wall on the studio side.

Then the new wall that you build just make it a single stud wall, join it to the ceiling. Don't build a staggered stud wall.

Then seal the floor boards between the ceiling joists with non hardening caulk, and then cut pieces of plasterboard to fit between the joists push up tight against the bottom of the floor boards of the room above. Secure these plasterboard pieces in place using wooden cleats that screw into the joists.

Once you've done that and it's all sealed, then build a completely detached set of stud walls within the space, and a new ceiling which rests on the top of those new stud walls.

The amount of plasterboard/mass layers that you use along with the amount of space between the outer and inner walls will depend on how much isolation you need and what frequency you need to isolate down to.

Paul
Paul
OpIvy
Posts: 11
Joined: Wed Oct 14, 2020 7:47 am
Location: North Qld, Australia

Re: Joining wall to ceiling

Post by OpIvy »

Thanks for the info
If I understand correctly, by resting the ceiling on the new outer stud walls, I'd need to install new joists to attach the ceiling plasterboard to.....?
I'd be concerned about losing to much height in doing that, which is why I was going to use clips/ channel to hang the ceiling off the joists. At the moment the height is about 2.5m to bottom of joists.

Do you think it'd be possible to 'float' the ceiling just above the finished walls by a few mm then fill and caulk the gap?
Paulus87
Senior Member
Posts: 652
Joined: Sun Mar 02, 2014 8:42 am
Location: Wales, UK

Re: Joining wall to ceiling

Post by Paulus87 »

OpIvy wrote:Thanks for the info
If I understand correctly, by resting the ceiling on the new outer stud walls, I'd need to install new joists to attach the ceiling plasterboard to.....?
I'd be concerned about losing to much height in doing that, which is why I was going to use clips/ channel to hang the ceiling off the joists. At the moment the height is about 2.5m to bottom of joists.

Do you think it'd be possible to 'float' the ceiling just above the finished walls by a few mm then fill and caulk the gap?
The new joists fit in between the existing joists, so you won't lose much more height than you would if you used resilient channel and clips. You could use clips, but you won't get as good isolation as completely unattached new joists.

Paul
Paul
OpIvy
Posts: 11
Joined: Wed Oct 14, 2020 7:47 am
Location: North Qld, Australia

Re: Joining wall to ceiling

Post by OpIvy »

Fair enough.
I'm also keeping cost in mind so adding about 9 joists is going to be a significant expense.
I guess it's like everything....putting money into where it matters. I'm just not sure this is one of those given the level of isolation I need. I'm mainly just doing vocals and DI guitar with some relatively quiet mixing

I'll have to give this some more thought....
Paulus87
Senior Member
Posts: 652
Joined: Sun Mar 02, 2014 8:42 am
Location: Wales, UK

Re: Joining wall to ceiling

Post by Paulus87 »

OpIvy wrote:Fair enough.
I'm also keeping cost in mind so adding about 9 joists is going to be a significant expense.
I guess it's like everything....putting money into where it matters. I'm just not sure this is one of those given the level of isolation I need. I'm mainly just doing vocals and DI guitar with some relatively quiet mixing

I'll have to give this some more thought....
If you only need a small level of isolation (below 50dB of transmission loss) then there is no need to build a room within a room.

Leave your block walls as they are just seal up all the cracks and gaps with a non hardening caulk.

For your stud walls apply at least two layers of 5/8" drywall (15mm plasterboard) to both faces either side of the studs. Fill the cavity with low density, cheap fluffy insulation.

For your ceiling, seal up all the gaps and cracks in the floor boards with a non hardening caulk, fill with insulation and then apply two layers of 5/8 drywall (15mm plasterboard) to the joists.

Doing all of that should provide you with enough isolation airborne sounds for your needs. You will still have impact noise from the room above and adjoining rooms, but this may be a workable compromise which will save you thousands.

Paul
Paul
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