Basic studio design and construction questions

Hi all- I'm currently looking at homes in the SE/NE neighborhoods of Portland, OR and as I look I'm evaluating the basements for potential studio build outs. I have a few basic questions based on what I'm seeing in many of the homes I'm seeing... It looks like most have thick concrete basements, so I'm hoping this will go a long way towards sound leakage to the outside world. The celings in almost all of these basements have been rather low, a little over 6-7 feet in most cases. Is this workable? What if there's low ducting the hangs down into the head space? What exactly is the function of the raised floor that I'm seeing in all of the studio designs? Does a raised floor play a more important role in the room the drums would be in or the amps (ie: could part of the studio be on raised floors while other parts weren't?) If anyone has any PDX specific thoughts I'd love to hear those as well. I apologize if these are elementary questions; I checked out the FAQ but didn't see any info on these topics. Thanks for the help. Lee

Lee - you just listed all the problems inherent in the typical US basement. the low ceiling height is the major problem. The raised floors you refer to are the floating floors that isolate each room but in your typical basement it's near impossible because of the limited ceiling height. Mind you IMO floated floors in a basement studio is overkill. Floated floors are more typically used to isolate one floor from the other - i.e. if you were to build on the second floor of an office block and didn't want your sound to get through to the other tenants. Floating floors also helps room to room isolation by stopping the flanking effect of the sound travelling through the floor from one room to another. In reality you rarely notice this effect and if you doo it's typically in the low frequencies only. why not look for a house with a good sized yard that you can build a new purpose built building for your studio rather than trying to get around all the problems associated with a basement design. I hope this helps cheers john

John- Thanks so much for the prompt and thorough response. Good points and info... I'm not sure what zoning here looks like in regards to building on a seperate building in the backyard. Perhaps some other PDX residents can chime in and let me know if they've experienced this before. My first thoughts on the matter though are that lots aren't generally lareg enough to allow for a ton of construction in the rear of the home and the small external garages I've seen thus far have been pretty small on the whole. Even with the low ceilings, I could still do the work though, yes? The advantage is that the house will be entirely mine and so I won't be bothering anyone upstairs. I just want to seal things up so I don't bother the neighbors. The studio will also not be a full on "client-based studio" for 24x7 outside usage. I'd like to do the majority of my own or my friends tracking there and then do extra tracking elsewhere if dictated by need... Thanks again for all of the feedback. I really appreciate it.

I'd assume you would need a special permit to build a freestanding studio - a house with a double garage is another option. Otherwise go with the basement idea - other factors to look out for are the damn posts the usually run the length of the basement and those pesky HVAC ducts that normally hinder designs in basement studios. :) cheers john

John Sayers wrote:

Mind you IMO floated floors in a basement studio is overkill... Floating floors also helps room to room isolation by stopping the flanking effect of the sound travelling through the floor from one room to another. In reality you rarely notice this effect and if you doo it's typically in the low frequencies only... cheers john

John- I've often asked myself the same question - sound is not traveling through the concrete slab on grade - why go to the extremes of a well floated floor? Is it correct to say that most "project studios" will be perfectly fine with the minimal flanking noise of a slab on grade basement situation? Is there another reason acoustically to float it? If so, is there an easier/cheaper way to deal with the acoustical issue than a full floated floor with rockwool and neoprene? Is the idea which Giles threw out (TryPLY rubber Roll Roofing with plywd and then Pergo a viable option? (sorry if I'm misquoting you, Giles) Thanks for all of your insight- John

I've been doing some more reading on all of this and wonder if the low freq. noise from drums or bass would carry out of the studio through the structure if the floor isn't floated. If I buy in Portland I'll be fairly close to my neighbors and would like to avoid any issues of noise if at all possible. What I'm hoping will work thus far is Mass-air/insulation/Mass walls for the most part and perhaps some resiliant sound isolation clips (I see them mentioned extremely regularly, so I'm guessing they're a good way to go). Thanks again for all of the help. I've been working towards a proper studio for 10 years now. I can't wait to get started...

But my question remains the same - how can sound travel to adjacent spaces via a concrete slab on grade? There is no diaphragm to carry the vibrations... What am I missing?

I don't know if I know the answer to your question, but my impression is that the structure (any surface in contact with the source of the vibration) itself absorbs and transmits these frequencies through the cement. Any surface in contact with the origionator of the sound (drum or bass amp), simply acts as a path for the vibration to travel, hence the need to float and isolate the vibrations or the low freq. can escape and leak into other spaces. Otherwise they'll travel through any surface that's in direct contact with them. This is all totally new to me though, so I may be off... (let's make that pretty likely). Does this make sense in reference to your question? I'm not sure about your reference to a "concrete slab on grade." I'm guessing you know more about all of this than I do:) I'm a newbie to construction all around...

John- Any comments on the floated floor vs slab question? Thanks alot! jpmanis