Shelving partition wall with large opening (acoustics / noise)

[MortarThePoint]

I'm planning some shelves for our family room on the 'wall' shared with the dining room. It's currently just open so the shelves would form the wall. They go either side of the chimney that has a large (approx. 900mm x 900mm) opening through to the dining room where the double sided stove fits. This opening represents a significant acoustic weakness. I could have a removable panel on one side or other of the stove opening for when there might be a rowdy dinner whilst kids watch a film for example, but it will always be a weak spot. That leaves me wondering if there is any point in having a significant partition at the back of the shelves. I could go for just 15mm plasterboard and 3mm hardboard as the the shelves are likely self supporting, though I think I would rather replace the 3mm hardboard with 12mm plywood or equivalent. That saves quite a lot of depth vs using 48mm or 70mm studwork (MF or timber).

 

Partition options (thickness) that come to mind are:

• Option A (18mm): hardboard and plasterboard [102mm]
• Option B (27mm): 12mm plywood and plasterboard [93mm]
• Option C (52mm): 12mm plywood, 25mm battens with 25mm APR insulation, and plasterboard [68mm]
• Option D (75mm): 12mm plywood, 48mm MF studs with 25mm APR insulation, and plasterboard [45mm]
• Option E (97mm): 12mm plywood, 70mm MF studs with 50mm APR insulation, and plasterboard [23mm]

 

Option E is equivalent to most of my other partitions which are 70mm MF with 15mm plasterboard either side. A thicker partition pushes the front of the shelves closer to the front to the chimney and I think they would look best recessed a bit (amount shown in [blue] based on 250mm shelf depth).

 

The black rectangle is a 55" TV which would weigh about 30kg and I think I would have studs within the shelf depth to cope with that load if hanging out on an articulating TV mount.

 

I am planning to use 33mm PSE softwood timber to make the shelves, either 250mm or 225mm deep. I don't imagine us hanging anything significant on the dining room side of the wall.

 

 

[Bozza]

How about doing a slimline stud partition eg option c then incorporating a system like this link below so you have a slimline wall but maximising the acoustic benefits.    I’m thinking just using boarding - options a or b - would act a bit like a drum ?  

 

https://sounddeadeninguk.co.uk/products/silent-cloud-1-2m-x1-2m-x-27mm-stud-walls-soundproofing-panel?variant=42620285780141&currency=GBP&utm_medium=product_sync&utm_source=google&utm_content=sag_organic&utm_campaign=sag_organic&cq_src=google_ads&cq_cmp=21032152032&cq_term=&cq_plac=&cq_net=g&cq_plt=gp&gad_source=1&gclid=EAIaIQobChMI5oWTrv65hAMVl5NQBh0DWgCGEAQYAiABEgIFGPD_BwE

[MortarThePoint]

1 hour ago, Bozza said:

incorporating a system like this link below

That would make the wall partition very good, but the big stove hole would still leak a lot of noise.

 

1 hour ago, Bozza said:

I’m thinking just using boarding - options a or b - would act a bit like a drum ?

That would be a worry. Hopefully the mass of plasterboard would help. I would hope that even if it acted a bit like a drum, it would be better than just nothing being there.

Edited February 20 by MortarThePoint

[Bozza]

For the double fireplace opening problem ….here’s a creative solution.   Large piece of what appears to be wall art / canvas on the chimney breast, however it’s actually constructed from an acoustically filled frame finished on the back in same colour as the wall.    Hinged at the bottom so it flips down and covers and seals the gap.  Could even replicate the art in the actual chimney beast, so you don’t have a big gap.  
 

or not hinged but made in a way with a lip that hides a rubber seal, so it can literally friction for / plug the fireplace gap with it. 
 

You could have one either side to create an airtight gap, because obviously the fireplace couldn’t be used if covered with certain materials.  
 

if you have tvs there could use same idea just hang the wall art/acoustic panel on another wall when not used.

 

do I win a prize ?

 

 

 

 

 

[MortarThePoint]

Some good thoughts