SOUND ON SOUND

[Eddy Deegan]

Hi all,

For reasons involving space, acoustics and the increasing need for a decent home office I've recently converted my loft into a decent sized domestic environment. I live in a typical semi-detached property built in the late '50s and the project involved squaring the walls at the gable and the rear of the property.

At this point the main building modifications are complete but I opted to do the insulation, internal plasterboarding and flooring myself. To give an idea of the space thus far, here is the view towards the party wall (the OSB boards on the right are covering the window apertures as there will be a delay of some weeks before they are ready) ...



... and here is the view looking the other way from that wall:



The picture above shows where the stairs come up. There will be a stud wall box over the stairs (at a height of about 80cm from the floor) and there will be a floor-to-ceiling enclosure to allow for a door to be fitted at the top of the stairs such that when it's opened it faces the party wall at the other end.

The supporting stud wall to the right of the stairs denotes a storage area under the eaves which I will be enclosing fully with an access door into it just to the left of the velux windows.

Much as it would be an interesting project to make this as robustly commercial grade in terms of music studio use as I can, my objectives are somewhat more domestic.

My main considerations are:

• The space is to be used for music and a home office
• The view out of the windows is important
• I create mainly electronic music but would like to do a bit of acoustic stuff now and again
• Accurate mixing is more important than accurate acoustic recording
• Soundproofing is much less of a priority than acoustic treatment (I don't work at high volumes)
• Notwithstanding the above I want to minimise downward noise from activity in the space to the bedrooms below
• Acoustic treatment is something I'll focus on more later - for now I'm mainly thinking about the structure

I've got enough Rockwool RW3 in house up there to insulate the space between the floor joists. The skin on the floor is 22mm flooring-grade tongue and groove chipboard, currently sitting there unfixed. I think it would be wise to install some form of isolation on the joists beneath the board and considered neoprene (which is an option) but also found Green Glue Joist Tape which looks an interesting option. Any thoughts on that?

The joists are pretty robust. They are at 300mm (or so) centres and consist of pairs of 2x4 timbers. I've not got a decent pic of them yet but here're a couple of the room while it was being constructed which give an idea:





There is also going to be a storage area under the eaves along the length of the room, with a couple of access points as shown here:



Due to building regs I'm limited in the options for insulation on the outer walls and ceiling (it has to be breathable and allow internal airflow across the top of the building) and will be installing various thicknesses of celotex in the ceiling, skeiling and walls which has good thermal properties but will be of little-to-no acoustic value. The plans also require an internal skin of alumaflex. However, there will be thick acoustic plasterboard on all the walls as well as the ceiling (the exact specs escape me right now but it was 20mm or thereabouts - I'll confirm later).

Electrician is coming next week (covid permitting) to install the lightning and spec up (and possibly start to install) about 30 power sockets. Also getting a new consumer board downstairs. He's already routed a bunch of cable with extra thick core up to the new space in preperation. I've spoken to him about the need to minimise the risk of ground loops and he's made some positive noises about that; we're going to discuss further when he gets here.

The main windows are floor-to-ceiling. Each is 2.1m wide and 1.8m high with a safety bar 80cm up. They are double glazed but the inner side consists of 6.8mm thick laminated glass with a transparent acoustic layer somewhere in the middle (my window supplier already knows my requirements well and did the rest of the house earlier this year!)

That's where I'm at right now. I'm basically trying to get the space usable and make sensible construction decisions with a view to adding acoustic treatment later.

Any advice on things I can be thinking about/talking to contractors about in the meantime to help achieve that goal are welcome!

[blinddrew]

Where is the desk going and which way is it pointing?

[Folderol]

Electrician is coming next week (covid permitting) to install the lightning and spec up (and possibly start to install) about 30 power sockets. Also getting a new consumer board downstairs. He's already routed a bunch of cable with extra thick core up to the new space in preperation. I've spoken to him about the need to minimise the risk of ground loops and he's made some positive noises about that; we're going to discuss further when he gets here

I would suggest a small local consumer unit actually in the loft itself (by the entrance maybe), and then star wiring to sockets, not ring.

I'm not sure what the regs are for lighting these days. For some time it has been recommended that access routes have their own lighting circuit, not connected to any individual landing. Each landing should in any case have its own circuit. That way if a lamp or fitting takes out a breaker you still have some light at every level.

[blinddrew]

Just listening to the latest government announcement, not sure the electrician will be coming next week if it's after thursday! :(

[Eddy Deegan]

Where is the desk going and which way is it pointing?

Nothing set in concrete at this point but my feeling both from an acoustic and logistical point of view is that the preferable arrangement is to have the desk and monitors at the party wall end (the one with the brick wall) facing down the length of the room.

[Eddy Deegan]

Just listening to the latest government announcement, not sure the electrician will be coming next week if it's after thursday! :(

Yes, we were looking at that too. My hope is that it falls under construction services, but we'll see. The electrician is a really nice chap and maintained a respectful distance from us at all times - he's no fool.

I would suggest a small local consumer unit actually in the loft itself (by the entrance maybe), and then star wiring to sockets, not ring.

I'm not sure what the regs are for lighting these days. For some time it has been recommended that access routes have their own lighting circuit, not connected to any individual landing. Each landing should in any case have its own circuit. That way if a lamp or fitting takes out a breaker you still have some light at every level.

All of the above has been touched on in conversations, but the meat of the chat is yet to come. He's spec'd up a consumer unit to replace the existing one we have (the latter is safe but not modern) and it will have dedicated circuits for both lightning and sockets in the studio.

Not directly related but in the meantime as well as running cables up there in preperation, I also got him to completely rewire the lighting circuits in all the upstairs rooms, plus we now have interconnected mains-powered (with per-sensor local battery backup) fire alarms in every room in the house.

[zenguitar]

Well done with the progress so far.

Andy :beamup:

[Eddy Deegan]

Thanks Andy - it's definitely been a project and there's a way to go yet but I'm finding it rewarding as much as challenging and can't wait to get everything up and running in there :thumbup:

[Eddy Deegan]

I'll post a proper plan diagram soon (need to measure and draw it out sensibly) but the two pressing questions in my head right now are:

1) The best isolation material to put between the flooring and the joists (Green Glue Joist Tape, Neoprene... ?)

2) Is it worth mounting the acoustic plasterboard on resilience bars given I'm not concerned about soundproofing, only achieving half decent internal acoustics after (potentially extensive) later treatment post-construction? If so, would the installation of those bars extend to both ceiling and walls?

I will be putting a layer of isolation between the floor and the plasterboard on the walls. I know it's less than ideal in terms of room geometry and the expanses of glass involved but I would like to make the best decisions I can under the circumstances at this point.

More questions will will follow I'm sure!

[zenguitar]

2) Is it worth mounting the acoustic plasterboard on resilience bars given I'm not concerned about soundproofing

It's definitely worth thinking about this a little more.

Right now you may not be concerned about soundproofing, but it might be something you might need to consider in the future.

As you are in a semi-detached building you have a party wall. You may well have a good relationship with your neighbours, but if they sell up you have no say in who will become your new neighbours.

Low power guitar amps can still get loud. And synths can produce a lots of bass energy.

And once you have the space, you might discover that your projects evolve and would benefit from recording slightly louder sources.

So whether or not you decide to go ahead with resilience bars, it would definitely be worth finding out how much it would cost. That way you can compare the marginal extra cost of fitting them now with the cost of retro fitting them in the future, and the opportunity cost of limiting your future options because you don't have them.

Andy :beamup:

[James Perrett]

One thought - you can buy carpet underlay made from recycled car tyres. I cut it into strips and used it to isolate everything in my studio from the outside structure.

One thing I wish I had done was to pack the cavity under the floor with Rockwool so that the floor doesn't resonate.

[Luke W]

Looks like a brilliant project Eddy, looking forward to seeing it progress. It's been quite a long time since I've been involved with this stage of building so I'll leave the construction questions to those more qualified to answer! The building regs regarding the insulation/airflow sound vaguely familiar from when the room that is now my studio was built. Sounds like you're going the right way for the best compromise though.

[Fishnish]

Looks good!
I notice you have some Velux type windows , (I saw you said you'd upped the spec for the other glazing - not sure if that applies to thes also?), but wonder what your plans are re taming any potential outside noise coming in via this route - I've got Veluxes myself in the studio room and have found they can be awfully noisy when the rain and wind blatters down on to them - much more so than vertically mounted glazing. Even when working with headphones on, on tasks that don't require open mics, the noise of the rain can be enough to make it impossible to work at times. Admittedly I do live on a storm lashed rock some way out into the Altlantic so geography plays a part in my particular experience.

My initial soloution was to fit external roller shutters so the rain doesn't hit the glass in the first place. They're remotely operated so if it starts to rain I can shut them without having to get up. This works well, but for truly inclement weather and as a second line of defence I butchered an old memory foam matress, cut inserts that fitted tightly into the window recesses and backed them with sturdy cardboard which was painted to match the walls. These are "locked" in place when needed with some dowels and cup hooks. Works pretty well and helps tame reflections off the glass too :)

When not in use they just sit in a corner under a rug. The dog likes to doze on them and keep an eye on proceedings, like a kind of big hairy cheese loving corner bass trap.

[Martin Walker]

Where is the desk going and which way is it pointing?

Nothing set in concrete at this point but my feeling both from an acoustic and logistical point of view is that the preferable arrangement is to have the desk and monitors at the party wall end (the one with the brick wall) facing down the length of the room.

That sounds like a good decision to me Eddy - as well as being preferable in most situations to fire down the long dimension of a room, pointing your monitors away from your neighbours is probably also a sensible choice ;)


Martin

[Eddy Deegan]

2) Is it worth mounting the acoustic plasterboard on resilience bars given I'm not concerned about soundproofing

It's definitely worth thinking about this a little more.

Right now you may not be concerned about soundproofing, but it might be something you might need to consider in the future.

Having thought it through a bit, I agree Andy. I've contacted the builders and made some alterations to the outstanding material orders I have with them.

I've also pushed back on the insulation they wanted me to use, as having checked I am sceptical that I have to use it, so once that's confirmed as an option I'll get another 60 or so square metres of RW3 and install that in the walls, ceiling and skeiling instead of the lightweight thermal foam stuff they were pushing me to use.

Meanwhile I've looked a bit into resilience bars and think I'll go for that as well. I'll have to do a proper cost-up tomorrow (and absorb the cost of the wooden batons I was going to use, as I've already got them here, but I'll chalk that up to experience!) with a view to using them for every surface other than the floor, which I think I'll sit on the Green Glue joist strips as they are very thin and headroom is a consideration.

One thought - you can buy carpet underlay made from recycled car tyres. I cut it into strips and used it to isolate everything in my studio from the outside structure.

One thing I wish I had done was to pack the cavity under the floor with Rockwool so that the floor doesn't resonate.

I saw these underlay tiles James... I may well use them as an underlay between the 22mm floor boarding and the laminate flooring I plan to install. Much as carpet is better acoustically I simply can't live with it so the plan is laminate flooring, but largely covered with a big rug at the business end of the room.