John Sayers' Recording Studio Design Forum Archive

Guys,

On my final layer of plasterboard on the control room side I have left a small gap for a backer rod along the wall and ceiling seems and my plan was to caulk over the top of this to seal the wall.

The problem is this will look pretty ugly compared to the normal nice straight line joint a plasterer will get with mud and tape where two wall or a wall and ceiling joins.

These seams will be very visible in the control room and I don't want them to look roughly done or have to put a timber moulding over top as the rest of the room does not have one. What do I tell the plaster to do?. Should he tape and mud over the caulk and backer rod to get a nice professional finish? Won't this defeat the purpose of the backer rod and caulk anyway? Maybe I should use a backer rod and then plaster? or should I forget the backer rod and caulk on this last layer and just fill the gap with plaster and tape as you normally would?.

These seams/joins will be a very visible part in the studio and I am not sure what to tell the plasterer to do?

Help??

JohnG

How about this? I´m planning to use it on my studio....

Hi There
The other three wall ceiling joins in the room do not have a moulding over top of them and I was keen to have the same finish along this wall / ceiling join.
There must be a way.
Anyone??
JohnG

How many layers now on your ceiling and wall, and how many caulk beads between ceiling and wall? Steve

Hi Steve,

The Control room wall I have just built is two layers of 5/8th.

The first layer of 5/8th is sealed with only caulk, no backer rod.

The wall at each end and the ceiling it joins is one layer of 1/2.

I am talking about sealing the second and final layer of 5/8th and I have left a small gap right around the wall to do this. The bottom is no problem because a moulding will cover the seam but the walls and ceiling join will be visible. I could always put up a moulding but I prefer a clean straight join as it will match up with the rest of the room.

Thanks

JohnG

If your first layer's caulk had backer rod so it wasn't a 3-point caulk joint, I wouldn't hesitate to suggest using backer rod and then just a standard inside corner mold with a light mud over; but without backer rod you will stand a good chance of having your inner caulk joint fail from movement. This would leave you with NO airtight joint, since sooner or later your mudded inside corner will ALSO crack (almost guaranteed)

How big an area is left at the joint (if you place a framing square up against the ceiling and wall, how big a crack is at the corner, behind the point of the square?) Steve

Steve,
I thought I would take some snaps for you.
(1) shows the corner where the wall, ceiling and new layer all join
(2) shows the new layer over the existing caulked layer
(3) unrelated - but how do I seal this hole where the multicore comes though the wall!!
I am thinking I may just caulk these new seams and run a small moulding over top and around the rest of the room. Maybe the best option?
ps ignore the bad screw sinking!!
JG

(1) shows the corner where the wall, ceiling and new layer all join
(2) shows the new layer over the existing caulked layer
(3) unrelated - but how do I seal this hole where the multicore comes though the wall!!
I am thinking I may just caulk these new seams and run a small moulding over top and around the rest of the room. Maybe the best option?

I agree; backer rod and caulk (no 3-point joints), and you can either finish with a moulding or with a flexible inside corner mold and LIGHT mud over, if you really don't want a moulding there.

The hole; what's on the other side of that gypsum - doesn't seem to be any insulation I can see... steve

Steve! I realize that the store send my 5/8" backer rod instead of 3/8" (for my 5/8" gypsum panels...)
Can i use the 5/8 backer or should i go for the 3/8?
Thanks!

Hi Steve,,
There is another layer of wallboard (the holes are not perfectlly lined up) and then there is insulation in the stud cavity (high density fibreglass). Its actually dark in colour that's why it looks like it's not there.
I have the same problem on the live room side going into the wall box further up and along the wall.
Thanks
JohnG

Julian, this would be better off in your thread for continuity; unless your gaps around the wall edges are REALLY LARGE, I doubt if the 5/8" stuff will fit and still leave room for a thick enough bead of caulk; you'll probably have to return it for the right stuff...

John, what about the OTHER half of the wall - is there(a) another hole lined up with it, or (b) do the wires go thru a stud or two before popping out the other side? (b is the correct answer ) Steve

My bad, steve, they sent me 3/8" backerod.
BTW, i´ll keep posting on "my" (or should i say "your";)) thread.
Thanks!

Hi Steve,

Answer is B

The cable goes through the control room wall at the bottom along the airgap in the insulation for about 3feet through a stud then up the wall about two feet and then through the live room wall. Similar hole on live room side as you see in the photo - basically holes are not lined up.
JohnG

OK, one more (wish I'd asked all of these at once, sorry) - is this a single or double framed wall, with or without RC, and if double framed how far apart are the frames?