Started this thread earlier today but with the snafu I will repost.

I am looking for input regarding the choice of 1/2" or 5/8" drywall. I do not have the budget to go two layers and GG and all of the other things one "should" do to isolate/insulate a HT.

Is there enough difference between 1/2" and 5/8" in that using 5/8" drywall will give me better insulation/isolation properties over 1/2"

Thanks in advance and to those who posted before the data loss thank you for your input and information.

dazed

5/8th has 25% more mass than 1/2. I believe the price difference is small, labor is basically equal. I'd say 5/8ths + insulation + sealing is your most cost effective solution.

Agreed

I replied with another question which is:

I just put up 3 layers of 1/2" in my room with GG between both layers. Originally I was going to do 2 layers and save what little space I already have. Then I decided I wanted more density after the first 2 were up and added a third with more GG.

The question for the experts is how dumb am I? Or will this actually be pretty effective compared to say 5/8 + 1/2 (aside from the extra 3/8" and 6 hours of labor). Basically am I getting some good value by having multiple GG layers?

Really more people should follow your example. Multiple layers of damping material is better than a single layer even if it's the same total amount of damping material just split into two layers.

So you have more mass and it's more thoroughly damped. End result? You'll have more isolation especially in the lower frequencies. This assumes that your room isn't horribly limited by flanking (like a hollow core, unsealed French door).

So not dumb at all. Quite the opposite :)

The 5/8" drywall will also give you a better end product from a visual standpoint as well. The 5/8" board is more rigid and won't flex to show imperfections in the framing as much as 1/2".

That's exactly right, which is why if you are using two dissimilar thicknesses of drywall you should install the thicker layer first.

5/8th has 25% more mass than 1/2. I believe the price difference is small, labor is basically equal. I'd say 5/8ths + insulation + sealing is your most cost effective solution.

Thanks the most cost effective solution is what I am looking for. I have been doing a lot of reading here and realize that there are much better and effective ways of isolating/insulating a HT but I am looking for the most economical.

dazed

I have a question as well.

When installing the low voltage boxes and the electrical boxes how far out do you set them?

If you are using 1/2 drywall do you set them to be 1/2 inch out from the stud? 5/8 for 5/8 drywall etc. etc.

That would make sense but there may be a trick I am not aware of.

Regards,

RTROSE

You got it right RTROSE. You'll see that the outlet boxes actually have indents at the common drywall depths (1/2" & 5/8"). Just line them up to your studs and nail them in place.

You got it right RTROSE. You'll see that the outlet boxes actually have indents at the common drywall depths (1/2" & 5/8"). Just line them up to your studs and nail them in place.


Well I figured it was pretty much bullet proof then again I have not worked with electrical for new construction so I am on a steep learning curve. Thanks!!

Regards,

RTROSE

That's exactly right, which is why if you are using two dissimilar thicknesses of drywall you should install the thicker layer first.Hey, haven't been in here for a long time.
Good to see people are still into it.
If I had it to do over again, I would have used 3 layers of 1/2" on the ceiling rather than 5/8 and 1/2.
Ted, do you think that this would've made a noticeable difference while still using 5/8 and 1/2 on the 4 walls?

We thought about it at the time, but with all of the pre-drywalling work that had to done, combined with the actual pain of hanging to 2 ceiling layers, pre-tubed GG, cutting for can lights, etc.,etc.,etc., the thought of hanging one more layer was so vile that we didn't do it.
In hindsight, these things fade away, thank God.:D

Hey Milt! How great to hear from you after these years.

No getting around it, I'm afraid. 3 layers is better than two.

#1 More mass, obviously, but that's a biggie

#2 The opportunity to use 2 skinny layers of damping rather than 1 thick layer means a more thoroughly damped mass.

This is especially beneficial on ceilings, since that's the big surface that's directly shared with the rest of the house. Throw everything you have on the ceiling.

Your walls may not have seen such a benefit, however. Technically 3 layers is certainly better, but not as good a return on investment as the ceiling.

Hi Ted.
Yeah, I still hang around here. I never have posted my build pics.
There were so many good ones at the time I was doing mine Chinadog, Ruben, Ronnie, ebr, etal., I never got around to it.
I also built an equipment rack with the "X" compound you guys so graciously provided. I really should post that too. That rack is a monstah.

In hindsight, I do wish I had put up 3 ceiling layers as that is the only area that has any discernable leakage to the upstairs. But it is still pretty good as it's only loud LFE that makes it through but that's always the rub isn't it, containing the low stuff.;)
I still have a few tubes of GG left that I need to find an application for.
I plan on replacing the carpet in the living room with hardwood and will have to find a way to put those tubes to good use.

Sorry for the Off Topic but I sometimes miss the build chat.