Three quick floating floor questions?

JohnGardner · Post by **JohnGardner** » Fri May 20, 2005 6:49 am

Hi all:

(1) stupid question - Is glue the best way to attach rubber pucks to the 2x4?

(2)Do the floating floor 2x4 beams need to be connected togeather or should I just line them up on the floor one by one. (see attached floor plan drawing with placement of 2x4 beams in red). I was just going to cut them to length, glue on pucks and lay them on the floor 600mm apart(eight across the 4.8m room) , fill the gaps with insulation and then nail the new 20mm flooring on top.

(3) Could someone please mark on the drawing or comment on, puck spacing. The room will weigh 2900pounds including gear etc. I am using 60durometer 25mm (1") pucks. The new floor is floated on existing wooden floor with support beams running the same way as my new "red" boards. These original beams are 1.2m apart.

Thanks

JohnG

the dreamer · Post by **the dreamer** » Fri May 20, 2005 3:51 pm

stupid question - Is glue the best way to attach rubber pucks to the 2x4?

In my opinion it will be the easiest way.

I assume that you are using EPDM/Neoprene.
I was recently advised by Eric Desart, that when you use EPDM/Neoprene the decoupling works on deformation (sides bulging out under load). The rule of the thumb is to aim on 10-15% deflection under load.
From this you can conclude the spacing. Take a puck of the desired size and load it until the desired deflection %age. From this you can calculate the beam and puck spacing.
Are you going to make a wooden(lightweight) floor? Than be aware of the "more" load areas...Walls...Desk, etc. You will need narrower spacing there to not bottom the pucks out and destroy the decoupling.

Also be aware of the Dead load/live load ratio! The heavier floor, the better!
Maybe reading this can clear this up:
http://forum.studiotips.com/viewtopic.php?t=1586
Also interesting:
http://forum.studiotips.com/viewtopic.php?t=1653

Florian

JohnGardner · Post by **JohnGardner** » Sat May 21, 2005 8:01 am

Thanks but that looks like rocket science to me!!.
Is there anyone who can do a rough calculation for me on puck numbers and spacing?. I'm a simple soul and those links and formulas are just over my head to be honest!!.
Thanks
JohnG

Dan Fitzpatrick · Post by **Dan Fitzpatrick** » Sat May 21, 2005 8:44 am

this page contains some EPDM compression data (arranged and paid for by sharward, one of our fellow forum-ites), although it is half the thickness you are using.

You may be able to figure out some answers by studying that. At least it will be better than doing it by guessing!

your material will compress more easily i assume because it is thicker, but i'm not sure ... good luck

Dan

Post by **sharward** » Sat May 21, 2005 9:06 am

Damn, Dan -- you win AGAIN!

Dan Fitzpatrick · Post by **Dan Fitzpatrick** » Sat May 21, 2005 9:17 am

BWAHAHAHAHAHAHAH!

JohnGardner · Post by **JohnGardner** » Sat May 21, 2005 10:37 am

So based on those tests I only need 10 pucks for the whole room at 300pounds per puck.
This won't work as I need more to create an even level over the room.
Is there such a thing as two many - If I just space them out at 24" on each of the eight members thats about 28-32 pucks.
Does that sound OK or is it a total over kill. Maybe 32" spacing?
JG

Dan Fitzpatrick · Post by **Dan Fitzpatrick** » Sat May 21, 2005 2:18 pm

hi john,

yes you can have too many. if you imagine using springs from a big diesel truck on a mini cooper, it wouldn't work too well, the springs would be essentially rigid so they wouldn't work ... you might as well not bother.

same the other way, if you use too few it's like using volkswagen springs on a railroad car. not going to work as the springs would "bottom out," or be squeezed to their maximum amount. again, a waste of effort.

i think the reason you are running into this problem may be that your room is too lightweight. you might want to step back and do more research before you continue.

there's a lot to know about floating floors, which i'm just learning myself. did you know for example that under certain circumstances having a floating floor can INCREASE low frequency transmission thru your floor?

in any case, good luck with your project!

dan

Post by **sharward** » Sat May 21, 2005 2:56 pm

Dan Fitzpatrick wrote:. . . you might want to step back and do more research before you continue.

there's a lot to know about floating floors, which i'm just learning myself. . .

Yeah -- even the guy who had those EPDM tests done and made the pretty graphs (er, uh, me

) has had to put the brakes on his own project, again!

But seriously... We're here to help, John. But Dan's right -- there's so much to learn, about floating floors and everything else. If you put an entire room on a floating floor, you can't afford to do it incorrectly, so sit back, get all caffeinated, and prepare to strain your eyes in the education/edification process here to the point of needing a new eyeglass prescription.

When you get stuck, post, and I'm sure you'll get some advice to unstick you. And when that happens, a whole lot of learning happens, and you're not the only one getting the education.

--Keith

JohnGardner · Post by **JohnGardner** » Sun May 22, 2005 7:35 am

Heres what I have come up with.

(1)The room is not light weight, it's just a small room - basically a drum booth.

(2) If I decrease the puck thickness and add more pucks the end result should be the same.

I need about 10 pucks at 3000 pounds at 25mm so I will need about 20-25 at 12.5mm for the same result.

Sounds simple - what do you all think!!

JohnG

Dan Fitzpatrick · Post by **Dan Fitzpatrick** » Sun May 22, 2005 10:42 am

Hi John,

YOur room looks to be bigger than the one i'm planning, yet mine will weigh 2 or 3 times what yours weighs. maybe you are not floating walls and ceiling??

as far as everything i've read, you want to keep your 1" thickness on the EPDM. thinner means stiffer which means higher frequency which is usually bad. also if you have little weight you want softer springs.

you haven't mentioned the square inch area of the surface of your EPDM pucks, maybe you can reduce that ...the area in contact with the room i mean.

with all due respect and certainly i'm not expert, it sounds to me like you're "winging it." i want to give you advice here but i don't want you to think i'm endorsing your plan (not that my endorsement is worth much anyways).

you may make things worse than if you didn't float, you have to be careful how you do it.

gotta run to dinner wife's calling