John Sayers' Recording Studio Design Forum Archive

Hello everyone!

My name is Peter Tielemann. I live in Bocholt, Germany.

I want to build a room to practice/rehearse for me and my band. We play heavy rock music and produce soundlevels of about 100-110 db. I wish to get the room as soundproof as possible. Further more i want to be able to make recordings in a sufficient quality. In the years to come, i plan to integrate the live-room into a (small) full studio environment with control-room and vocal booth.

Budget:
5000-6000€ (only live-room)

Facility:
Basement of a free standing single-family home. The next neighbour resides 7m away on the north side of my house. Above the basement lie two floors with the same dimensions. The outer walls and the floor of the basement are made of reinforced concrete (35cm thick). The floor currently has another „floated“ floor on top (4,5cm polystyrene + 8cm concrete). The inner walls are made of lime-sand bricks in various depths. The 11,5cm thick masonry has no static use for the building and could be removed. The ceiling also consists of 16cm steel-reinforced concrete.
Dimensions of the room:

5,05m L 3,60m W 2,375m H (with current floating floor: 2,25m)

I did some basic soundmeter measurements with a pa-monitor playing a rock song with a peak of 95 dB. I got an average sounddamping of 40 dB in the adjacent rooms and outside oft he building. The highest dB values were measured directly above the room with a peak of 57 dB. So, the room above the ceiling (where the sleeping-room of my family are located) seems to be the weakest point in isolation. In the storage room adjacent to the planned live room sewer ducts go through the ceiling into a bathroom above.

My thoughts until now:
After reading some books (incl. Rod Gervais) and threads in this forum i decided to build a room in a room. I guess that the already installed „floating“ floor won’t do me any good in sound-insulation, because it is not designed for this purpose. So i developed the idea to pour it out completely and build my room directly on the underlying concrete slap. This will gain me another 12,5cm roomheight.

1. Is this appropiate?

With leaving the existing walls intact and using the room ratio formula of Louden (1:1.5:2.1) i could build a room which fits quite well into the existing structure without wasting to much space.

2. Should i go with the rectangular room, or is it worth to flay some walls (this would bring much more construction effort to realise)?

Cheers!

Peter

The sketchup plan of my basement (filesize is too large to upload directly onto the forum-server):
http://narrenbrut.de/onewebmedia/Keller ... ustand.skp

To illustrate my second question, here are some drawings:

Hi there Peter, and Welcome!

The floor currently has another „floated“ floor on top (4,5cm polystyrene + 8cm concrete).

Was that done acoustically, and properly floated? Or was that just for thermal isolation purposes?

So i developed the idea to pour it out completely and build my room directly on the underlying concrete slap. This will gain me another 12,5cm roomheight.
1. Is this appropiate?

If you don't need it, and it isn't doing anything useful, then yes, definitely, take it out. That extra height will be good for the room, acoustically.

To illustrate my second question, here are some drawings:

This is going to be a live room / rehearsal room, so it needs to be as big as possible. You don't need to splay the walls if that would make the room smaller: there are better ways of dealing with flutter echo and other acoustic issues. On the other hand, if splaying a wall will increase the volume of the room, then yes, it would be a great idea to do that!

Also, get rid of the angled "sound lock" area: that is wasting space, and you will get a very good "sound lock" effect from just using a pair of doors back-to-back, one door in the inner leaf, one in the outer leaf.

The sewer pipe: design your walls so that the sewer pip runs inside the cavity between the two leaves. Wrap it in insulation, then wrap MLV around that, and seal that with duct tape. I had a similar problem with a sewer pipe above a home theater a few years back, and this solution worked very well.


- Stuart -

Hi Stuart, thanx for your fast reply!

The floating floor was constructed for thermal isolation purpose only. Actually, the greater room on the left of the planned live-room (where i want to construct the control room later on) has an floor heating system implemented inside. So i can remove it only in the live-room area.

Based on your reply, i made another drawing:

The soundlock could be used as a vocal booth in this design. But how do i calculate room modes in the live-area? Or should i neglect them?

Peter