Upstairs studio in a wooden house

[askomiko]

Hello!

Ok, so here's a project that isn't halfway built before the first post! I'm slowly starting to plan and research for a man cave studio on the unbuilt upper floor of my house. (I promise I'll try to be more careful than the other finnish guy some time ago.) I'm not in a hurry, I'm happy if I'm finished a year from now. Anyways, the house is made of wood like most houses around here are. Bad for isolation, but on the other hand, the basses go through the walls and might not create as bad acoustical problems. My main goal would be to have the first good sounding room for mixing in my life. No crazy nulls and peaks like I've always had so far in untreated small rooms. The second goal is of course not to leak so much sound that the wife gets a nervous breakdown. It will not be used for drums, nor 100db mixing at midnight. I'd say 95db(A) at the mixing spot for the short loudest moments, but 80-ish for normal use. Maybe a 40db reduction could be a high, ambitious goal with wood house and upper floor setup?

My budget is 20 000e for the whole project. I'm not a builder myself, so I will employ someone to build the important parts: the insulation, walls, electrics, roof, HVAC (the current idea is to add the air input and output into the current heat recovery ventilator system of the house, and add a heat pump for heating/cooling). I'm afraid the 20 000e is not enough for all this.

The space has only a wooden floor at the moment, so it's almost a blank canvas. However, there are some limitations.

1. Brick chimney. This is not going anywhere.

2. There are no inside stairs at the moment. I'm almost thinking it could stay like this, the current entrance is from the short end, from outside stairs. In reality, I guess proper indoor stairs will be built so that I don't have to run outside the house to get there. The stairs are a big limitation, since the layout of the first floor of the house drastically limits the possibilities for their placement. I haven't consulted with builders yet if it would be be possible to arrange things so that it's less intrusive, but I believe the stairwell will appear in a stupid spot in the middle of the floor, which eats a lot of usable space. The stairwell will need a door, so it will also need walls around it. Entrance from the side, through a (non-existent at the moment) wall would be greatly preferred. This will be the first problem that needs solving with builders.

The space itself is (L) 10.4m x (W) 3.45m x (H) (no inner roof yet, maybe 2,70m). It will have a straight roof despite being on the attic. I don't mind using quite a lot of the depth for deep front and back wall bass traps, hangers etc.

sketch2.JPG

(I spent three hours with the sketchup and that's the best I could do, it's a true horror experience at the moment, I hope I get better quick! My mouse hand already hurts )

If I don't build the stairs, the whole space would be available. I was playing around with the amroc mode calculator and noticed that lengths of 4.0 - 4.7m would put the room ratios in the Bolt area. So that's a first, basic idea for the room length.

Here's a picture from the entrance door at the moment. The small window at the back wall will be removed, as will the weird box around the chimney. The air ducts at the back wall are a mystery for me, they'll require some attention.

3.jpg

Ok, so here are some things I'm pondering:
Option 1: Let a constructor build a normal room with the usual insulation in the usual spots. I'd have a normal room with reqular vapor barriers in the correct spot, nearest the inside wall board. I live in Finland, where the winters are cold. I've read from several places that setting up huge bass traps against a regular outside wall is a no-go: a bale of rockwool against an outside wall acts as a thermal insulation on a wrong side of the vapor barrier, and moisture starts to accumulate behind the trap. Solution: leave a 10cm air gap. This eats some space, but it's not a disaster, and I'd have a normal room available too. Potentially the cheaper way.

Option 2: Be smart with the build, since there's nothing done yet. Have detailed plans with all the acoustic treatment included in them. Have a pro designer figure out the correct placement for the vapor barrier in this scenario. In this scenario, the plans would need to be detailed that the builders can follow them and have good sounding and safe "no mold disaster in two years" results.

#3: The difficulty of isolating sound in a wood house upper floor. This is a potential drawback, but not a show stopping disaster. I could be doing music almost happily in a bedroom downstairs with no special isolation, but since I have the space available, this project would be a huge upgrade in taming the room resonances, and hopefully isolation-wise too! What kind of figures can be reasonably achieved?

Gyproc, Isover and hammer, here I come!

[Gregwor]

I'd say 95db(A) at the mixing spot for the short loudest moments, but 80-ish for normal use.

Your measurements should be in C weighting:

A vs C Weighted SPL.png

Maybe a 40db reduction could be a high, ambitious goal with wood house and upper floor setup?

Maybe is a good word to use.

My budget is 20 000e for the whole project. I'm not a builder myself, so I will employ someone to build the important parts: the insulation, walls, electrics, roof, HVAC

That's a great budget if you were doing more yourself. I'm not sure what labour costs in your area, but that could eat into a lot of it. You may want to consider trying to take on more yourself. Framing, for example, is not difficult as long as you follow proper building construction. You should have all of that figured out by the time you have a completed SketchUp design

(the current idea is to add the air input and output into the current heat recovery ventilator system of the house, and add a heat pump for heating/cooling). I'm afraid the 20 000e is not enough for all this.

You'll have to figure out (once you get your layout sorted) whether or not your existing HRV can handle the required CFM and static pressure of your studio. Good idea about the heat pump. That will probably be the easiest and cheapest solution.

If I don't build the stairs, the whole space would be available. I was playing around with the amroc mode calculator and noticed that lengths of 4.0 - 4.7m would put the room ratios in the Bolt area. So that's a first, basic idea for the room length.

It's good to be within the Bolt area, but as long as you pass the 3 tests on Bob Gold's Room Mode Calc site, you're probably in decent shape (no pun intended). Remember though, depending on your room construction, your ceiling height could drop drastically and then all of those room dimensions go down the toilet. You have to figure out what type of construction you can use. Also, check out listening room specs such as ITU-R BS.1116-3 or EBU Tech 3276. You need to try and have your room at least 20 m2.

The air ducts at the back wall are a mystery for me, they'll require some attention.

If you're using the end of your space, then yes, you'll for sure have to figure that out.

Option 1: Let a constructor build a normal room with the usual insulation in the usual spots. I'd have a normal room with reqular vapor barriers in the correct spot, nearest the inside wall board. I live in Finland, where the winters are cold. I've read from several places that setting up huge bass traps against a regular outside wall is a no-go: a bale of rockwool against an outside wall acts as a thermal insulation on a wrong side of the vapor barrier, and moisture starts to accumulate behind the trap. Solution: leave a 10cm air gap. This eats some space, but it's not a disaster, and I'd have a normal room available too. Potentially the cheaper way.

Cheaper, maybe a bit. If you do go with a "normal" room, you will probably opt to use RSIC clips and hat. Those are actually quite expensive. The vapour barrier concern may be an issue, but regardless, you're going to have a ton of insulation on the inside of your drywall. And in a true MSM design, both the outer leaf and inner leaf are hermetically sealed. So air flow behind any insulation isn't really going to be a "thing". Personally, I would just use normal building methods and put treatment insulation up as needed.

Option 2: Be smart with the build, since there's nothing done yet. Have detailed plans with all the acoustic treatment included in them. Have a pro designer figure out the correct placement for the vapor barrier in this scenario. In this scenario, the plans would need to be detailed that the builders can follow them and have good sounding and safe "no mold disaster in two years" results.

Less time. More money. Awesome results. If you're already concerned about money though, this might not be an option for you. Granted, a design for a smallish control room wouldn't cost too much.

#3: The difficulty of isolating sound in a wood house upper floor. This is a potential drawback, but not a show stopping disaster. I could be doing music almost happily in a bedroom downstairs with no special isolation, but since I have the space available, this project would be a huge upgrade in taming the room resonances, and hopefully isolation-wise too!

The first thing you need to do is find out how much weight (live and dead loads) your joists can handle. Figure out how much weight you will place on the floor depending on whether you build a room in a room or go the clip and hat route. Also, you would have to dampen the cavities under the existing floor and beef up the floor with more weight (such as 2 layers of 3/4" TnG OSB with Green Glue in between. Also, take into consideration how much weight is currently placed on the joists (mechanical and drywall below)

What kind of figures can be reasonably achieved?

Until you figure out what sort of room you can build, it's impossible to give you any figures.

Greg

[askomiko]

A few more hours of Sketuchup tendonitis resulted in somewhat successful import of the house layout picture. This arrangement would leave the room length at around 5m.