Building a house with studio in basement

[Joachim]

Hello,

I have been following this forum for a while now, and it's really great to have so much info about building a recording studio.

We are building a house, and I already received some plans from our architect. There's also room for a studio in the basement.

Purpose and objectives:

A homestudio for non professional use, but with good acoustic isolation and sound characteristics. It should be possible for a band to play without disturbing my family. I play in a blues band, but it's possible that the studio will also be used for rock or even heavier stuff.

Location:

The studio will be in the basement (concrete construction) under the garage and washing room. There's a distance of approx. 11 meters (36.09 feet) to the next neighbour.

Dimensions:

See the pic below: the yellow part is for the studio (never mind the wall between the big and the small part and the door in the small part, which shouldn't be there). So there's an area of 5.9m (19.36 feet) x 4.6m (15.09 feet) and an area of 2.40m (7.87 feet) x 3.35m (10.99 feet).

A height has not been specified until now.



Questions:

I know I still have lots of reading to do, but I'm concerned that I'll make wrong decisions that will make future steps to soundproof the room a lot harder. So I would really appreciate any advice and/or help with following issues:

1. Is it OK if I let my architect build a concrete basement, just like he would do in an ordinary house without studio plans? Or are there specific steps to bear in mind for soundproofing the room?

2. Will I need 'a room in a room' construction with a floating floor?

3. What would be the best height for the basement?

4. What is the best solution for soundproofing the studio? I am willing to spend what's necessary (as long as it's reasonable): I want the living areas to be as free from noise as possible.

5. Design tips are also highly appreciated. I was thinking that the small part above might become a drum booth.

6. How about ventilation?

Many many thanks in advance.

[sharward]

Welcome to the forum, Joachim!

I don't have much to contribute here, except a few thoughts about height. Understand that nobody on this forum has ever complained about having space that is too tall -- in fact, it is usually quite the opposite, especially when considering how much floating a "room within a room" costs in terms of headroom, sometimes to the point of being illegal. So, as a rough idea, since you're building from scratch anyway, go with a 3.5 meter ceiling height in your basement if you can, and perhaps 4 if you can manage it. That may be more than you'll need, but I doubt you'll ever complain that your ceilings are "too high" in your finished space!

Except for the stair climbing, of course... But that's what hydraulic elevators are for!

Hey, you can dream a little!

[Joachim]

Thanks for your reply sharward.

A minimum height of 3 meters shouldn't be a problem and was also what I had in mind. I'll talk to our architect about it.

On the other hand I'm not sure if I really need the floating floor. Maybe a sheetrock ceiling will provide enough isolation, considering the fact it's a basement studio?

[knightfly]

1. Is it OK if I let my architect build a concrete basement, just like he would do in an ordinary house without studio plans? Or are there specific steps to bear in mind for soundproofing the room?

As long as you use solid concrete for basement walls (not hollow blocks) the other consideration is to make your upper floor joists (the ones that will be your studio ceiling joists) larger so they will support a dead load of at least 20 PSF (100 kG/m^2) - that will allow you to put more mass on the upper floor and still support at least two layers of 15mm gypsum under the joists for your studio ceiling. Where you're doing this from the beginning, it will be easier to add the needed mass for good isolation. I would suggest at least one extra layer of 19mm MDF as an addition to your subfloor for the living space, with all layers glued to joists in addition to nails/screws.

The studio ceiling will give better isolation by using separate frames to support the ceiling panels; these can be done after the fact.

If you want really good isolation, tell your architect you want the basement floor strong enough to support an extra 270 kG/m^2, so you can float a 100mm concrete floor and build your walls/ceiling floated - concrete transmits sound pretty well, so it's possible that the sound from your studio would travel along the concrete floor, up the concrete walls, into the upper level framing, and re-radiate into nearly any room in the house. Building a proper floated room will pretty much eliminate that problem.

2. Will I need 'a room in a room' construction with a floating floor?

See above.

3. What would be the best height for the basement?

12 meters Seriously, 3 meters would be minimum and 4 would be better.

4. What is the best solution for soundproofing the studio? I am willing to spend what's necessary (as long as it's reasonable): I want the living areas to be as free from noise as possible.

Solid concrete outer walls, insulated 300mm air space, double 15mm gypsum inner leaves, similar construction for ceiling, floated concrete floor. Double air lock solid core doors with drop seals.

5. Design tips are also highly appreciated. I was thinking that the small part above might become a drum booth.

Above what? Are you referring to the smaller of the two light-colored rooms?

6. How about ventilation?

This is part of why you need more ceiling height; you can tie into the normal house air conditioning (if it exists) but you will need to use lined ducts, the ducts need to be at least TWICE the cross-sectional area that would normally be used, and each duct needs to run separately from the air handler to each room and have at least two 90 degree bends from start to finish.

The bends attenuate sound transmission; the larger cross-section gives as much air flow with slower velocity; air noise is approximately = to the 4th power of the velocity, so lowering the velocity will make a big difference in air noise.

Hope that helps... Steve

[Joachim]

Thank you so much! I'm seeing our architect thursday, and I will discuss your suggestions with him.

5. Design tips are also highly appreciated. I was thinking that the small part above might become a drum booth.

Above what? Are you referring to the smaller of the two light-colored rooms?

Yes I am. Sorry if this wasn't clear.

[knightfly]

That should be large enough for a drum booth; you will probably want to build at least one slot resonator for it, most likely tuned to around 300 hZ and taking up most of one of the short walls... Steve