I've just taken down a dilapidated saggy lath and plaster ceiling in
the sitting room of my victorian terrace. For all its faults it was
pretty good at soundproofing between the sitting room and the bedroom
above it. I'm getting worried that putting up a single layer of
plasterboard and skimming it will give virually no soundproofing.

So, I've been looking at this:
http://www.customaudiodesigns.co.uk/...toceilings.htm
As you can see it's basically a system in which the plasterboard is
screwed not directly to the joists but to "resilient bars" which
insulate it from the existing structure. There would also be some
acoustic quilt and acoustic membrane thrown in for good measure, plus
two layers of plasterboard.

But now I'm thinking that maybe I'm getting this out of proportion.
Does this look over the top for soundproofing within a house? Any
simpler ideas?

Martin Pentreath wrote:
I've just taken down a dilapidated saggy lath and plaster ceiling in
the sitting room of my victorian terrace. For all its faults it was
pretty good at soundproofing between the sitting room and the bedroom
above it. I'm getting worried that putting up a single layer of
plasterboard and skimming it will give virually no soundproofing.

Well, use two or three layers then! Don't forget to rake out at
the top of the wall to allow the PB to push into a "slot" all
around the room:


[] [] [] [] -joists
####========================= -plasterboard
####@
wall- ####@
####@ - lime render
####@

Two layers of plasterboard is good especially if you liberally paste the first layer with PVA to bond the second to it - it effectively becomes one giant thick sheet of plasterboard which is more noise/vibration resistant due to its mass. Other than that, I think you'd be better off looking at thicker carpets/underlay upstairs or maybe take up floorboards & fill the void with loose insulation material. Isolating the ceiling from the joists as you suggest might at best only reduce impact noise (eg. footsteps) rather than airborne noise (eg. TV) so I would say would not be worth the effort.

Martin Pentreath wrote:
I've just taken down a dilapidated saggy lath and plaster ceiling in
the sitting room of my victorian terrace. For all its faults it was
pretty good at soundproofing between the sitting room and the bedroom
above it. I'm getting worried that putting up a single layer of
plasterboard and skimming it will give virually no soundproofing.

So, I've been looking at this:
http://www.customaudiodesigns.co.uk/...toceilings.htm
As you can see it's basically a system in which the plasterboard is
screwed not directly to the joists but to "resilient bars" which
insulate it from the existing structure. There would also be some
acoustic quilt and acoustic membrane thrown in for good measure, plus
two layers of plasterboard.

But now I'm thinking that maybe I'm getting this out of proportion.
Does this look over the top for soundproofing within a house? Any
simpler ideas?


2 rather obvious simpler ideas:

1. Push the L&P back up using a wood prop + wood sheet, pour diluted
pva glue on top to stick it back to joists, and when done skim the
ceiling. This should last very well.

2. Fit laths, and plaster with lime. You can do all that yourself with
no skill if you let the plasterer do the final skimcoat. Much faster
and easier than wood laths are reed matting, metal EML, or wired bamboo
fencing.

People dont seem to think before they take these things down.


NT

wrote:
Martin Pentreath wrote:
I've just taken down a dilapidated saggy lath and plaster ceiling in
the sitting room of my victorian terrace.

2 rather obvious simpler ideas:

1. Push the L&P back up using a wood prop + wood sheet

Erm, difficult.

In article .com,
"Martin Pentreath" says...
I've just taken down a dilapidated saggy lath and plaster ceiling in
the sitting room of my victorian terrace. For all its faults it was
pretty good at soundproofing between the sitting room and the bedroom
above it. I'm getting worried that putting up a single layer of
plasterboard and skimming it will give virually no soundproofing.

If the old ceiling was adequate then this should give good results
without expensive materials or complicated contruction:
two layers of 12mm plasterboard overlapping so the joints don't
coincide, an inch or two of dry sand on top of that, then fill to
floor level with rockwool. Stuff any gaps with rockwool or fill with
flexible mastic.

In article , Rob Morley
writes
In article .com,
"Martin Pentreath" says...
I've just taken down a dilapidated saggy lath and plaster ceiling in
the sitting room of my victorian terrace. For all its faults it was
pretty good at soundproofing between the sitting room and the bedroom
above it. I'm getting worried that putting up a single layer of
plasterboard and skimming it will give virually no soundproofing.

If the old ceiling was adequate then this should give good results
without expensive materials or complicated contruction:
two layers of 12mm plasterboard overlapping so the joints don't
coincide, an inch or two of dry sand on top of that, then fill to
floor level with rockwool. Stuff any gaps with rockwool or fill with
flexible mastic.

Even just 2 layers of overlapped 12mm pb should be pretty effective.
--
Tim Mitchell

Chris Bacon wrote:
wrote:
Martin Pentreath wrote:
I've just taken down a dilapidated saggy lath and plaster ceiling in
the sitting room of my victorian terrace.

2 rather obvious simpler ideas:

1. Push the L&P back up using a wood prop + wood sheet

Erm, difficult.

standard practice for repairing failing L&P

NT

wrote:
Chris Bacon wrote:
wrote:
Martin Pentreath wrote:
I've just taken down a dilapidated saggy lath and plaster
ceiling in the sitting room of my victorian terrace.

2 rather obvious simpler ideas:

1. Push the L&P back up using a wood prop + wood sheet

Erm, difficult.

standard practice for repairing failing L&P

I think he means that it's in rubble bags out the back now.....

bigcat wrote:
Chris Bacon wrote:
bigcat wrote:
Martin Pentreath wrote:
I've just taken down a dilapidated saggy lath and plaster ceiling in
the sitting room of my victorian terrace.

2 rather obvious simpler ideas:

1. Push the L&P back up using a wood prop + wood sheet

Erm, difficult.

standard practice for repairing failing L&P

Erm, read Mr. Pentreath's first sentence....

"Martin Pentreath" wrote in message
oups.com...
I've just taken down a dilapidated saggy lath and plaster ceiling in
the sitting room of my victorian terrace. For all its faults it was
pretty good at soundproofing between the sitting room and the bedroom
above it. I'm getting worried that putting up a single layer of
plasterboard and skimming it will give virually no soundproofing.

So, I've been looking at this:
http://www.customaudiodesigns.co.uk/...toceilings.htm
As you can see it's basically a system in which the plasterboard is
screwed not directly to the joists but to "resilient bars" which
insulate it from the existing structure. There would also be some
acoustic quilt and acoustic membrane thrown in for good measure, plus
two layers of plasterboard.

But now I'm thinking that maybe I'm getting this out of proportion.
Does this look over the top for soundproofing within a house? Any
simpler ideas?

It depends how noisy you plan to be. I would have thought that a single
layer of 12mm plasterboard would be adequate for most houses. However, you
can always add a second layer of 12mm plasterboard (with staggered joints)
if you find you need to increase the soundproofing once that is up.

Colin Bignell

It's true, I didn't think first, and the ceiling is now in the skip!
Even with hindsight, I think that trying to save it may have been
complicated - it was cracked and uneven and covered in nasty
woodchip-type paper and I've had my fill of trying to get that stuff
off the hallway and stairs. It also had some not-very-special old
cornicing which was falling off in places and would have been hard to
repair and may have looked odd anyway with a skim coat on the rest of
the ceiling.

Anyway, no use crying over skipped ceilings. I think I may just go for
two layers of plasterboard with some acoustic mineral wool to be on the
safe side.

In message .com,
Martin Pentreath writes
It's true, I didn't think first, and the ceiling is now in the skip!
Even with hindsight, I think that trying to save it may have been
complicated - it was cracked and uneven and covered in nasty
woodchip-type paper and I've had my fill of trying to get that stuff
off the hallway and stairs. It also had some not-very-special old
cornicing which was falling off in places and would have been hard to
repair and may have looked odd anyway with a skim coat on the rest of
the ceiling.

Anyway, no use crying over skipped ceilings. I think I may just go for
two layers of plasterboard with some acoustic mineral wool to be on the
safe side.


I find that a wooden frame to fit the 2 layers of plasterboard creates a
space which dissipates the sound - a bit like double glazing where the
bigger the gap between the glass, the better the soundproofing. Then,
upstairs, a layer of hardboard, Cloud 9 Cumulus underlay, and carpet,
makes for pretty good proofing.

--
Richard Faulkner

In message , Richard Faulkner
writes
In message .com,
Martin Pentreath writes
It's true, I didn't think first, and the ceiling is now in the skip!
Even with hindsight, I think that trying to save it may have been
complicated - it was cracked and uneven and covered in nasty
woodchip-type paper and I've had my fill of trying to get that stuff
off the hallway and stairs. It also had some not-very-special old
cornicing which was falling off in places and would have been hard to
repair and may have looked odd anyway with a skim coat on the rest of
the ceiling.

Anyway, no use crying over skipped ceilings. I think I may just go for
two layers of plasterboard with some acoustic mineral wool to be on the
safe side.


I find that a wooden frame to fit the 2 layers of plasterboard creates
a space which dissipates the sound - a bit like double glazing where
the bigger the gap between the glass, the better the soundproofing.
Then, upstairs, a layer of hardboard, Cloud 9 Cumulus underlay, and
carpet, makes for pretty good proofing.


Or you could fit something like Reduc Strata on the floor above, before
fitting the carpet. Add this to the plasterboard, and you would be well
in excess of building regs requirements, (not that you have to comply
with them).

--
Richard Faulkner

On 10 Jun 2005 04:27:51 -0700, clueless wrote:



2. Fit laths, and plaster with lime. You can do all that yourself with
no skill if you let the plasterer do the final skimcoat.

LOL
Floating a ceiling to be flat is about a skillfull and dificult job as
you get! Datums, screeds, manipulating a straight edge above your head
whilst perched ontop of some kind of scaffolding.

Steve Walker wrote:
wrote:
Chris Bacon wrote:
wrote:
Martin Pentreath wrote:

1. Push the L&P back up using a wood prop + wood sheet

Erm, difficult.

standard practice for repairing failing L&P

I think he means that it's in rubble bags out the back now.....

ah got ya General vs specific.

NT