Hi /diy/, ESL from south america and I was wondering if you could help me.My house has a shitty, badly built, barely insulated wooden guest house in the backyard, and I want to insulate it thermically and acoustically. The interior walls are mostly made of hardboard, with plywood in a few places. Frames are made of timber and filled with polystyrene for insulation.I am thinking of replacing the polystyrene with rock wool, and the hardboard and plywood with drywall in the exterior-facing walls, mostly because it's cheap and google says drywall is a better acoustic insulator. However, judging by the videos I've watched on yt, drywall seems difficult to work with: I'd have to use plaster for finishes, I'm not really skilled and I don't care about looks. Meanwhile, I could just nail the plywood to the frames and call it a day.I was also thinking of adding metallic studs in a few places, but while these are cheaper than structural timber, they also seem to be pretty complicated to with with, because of their thermal expansion. I'd also have to insulate them with some plastic tape, which in the end makes them more expensive than timber.Questions:- is it true that drywall is better acoustic insulator? Do I really need to use plaster with it? What if I just slap the plywood on top of the drywall to avoid having to use plaster?- do metallic studs need to be insulated acoustically? Beyond the plastic tape, do I need to use plastic nails or something to avoid the noise? How the fuck do you attach the drywalls to metallic studs?(continues)
>>2973088(cont.)The house has had termites for many years (though not the terribly destructive type you guys have in the US), so I also plan on wetting all the wooden surfaces (timber, plywood, hardboard, maybe even the paper in the drywall) with a mix of borates, with the added benefit of making everything fire-proof (see https://forestryforum.com/board/index.php?topic=92568.0, https://sawmillcreek.org/threads/home-made-bora-care-timbor.233066/ and https://www.youtube.com/watch?v=heCV7zlvhi8 if you want o know how this stuff is made).Can you suggest some alternative materials that cover all the bases (thermal+acoustic insulation, fire-proof, not vulnerable to termites, and relatively cheap)?My plan is as follows:- undo some of the internal hardboard/plywood siding,- apply borates mix to all surfaces, as well as to the siding that was just removed,- let it dry for a couple of days,- slap a few small pieces of drywall,- add the rock wool batts,- slap the drywall boards,- maybe add the plywood on top.Is this a good plan? Am I missing something?
Please /diy/
Good plan for dealing with termites. Yes it is true that drywall is a good noise insulator, the best way to reduce exterior noise getting into the building is air sealing, so taping and drywall compound on the seams between hung drywall will help a lot, otherwise caulk or foam all holes and gaps will help too. I don't know about metal stud acoustics but can screw drywall to metal studs with fine thread drywall screws afiak
>>2973593I won't use plaster compound, I'm too lazy for that shit. I'll try caulk or foam. Which one do you recommend for finishes? Should I get both?Also, how do you deal with corners, like, between walls, or in windows? Should I just use foam and wooden corners everywhere?
Didn't read. Look for air gaps then fill them. Windows and doors obviously are the biggest culprits. Double pane windows makes a big difference if you can upgrade those. Heavy curtain at the windows helps absorb sound.
>>2973088Your guest house is gonna look like shit if you ply all the interior walls. But yeah you can cover drywall with whatever you want if you really don't care about looks. Be very careful if you have a bathroom, it needs moisture resistant drywall boards and obviously the wood shit has to be sealed.>replace EPS with rockwoolThis is not going to add a lot of insulation, but rockwool is fireproof (though EPS also has fire resistant variants). Focus on insulating the roof, give it a very thick insulation layer, like 30cm minimum, and replace the windows if you only have single-pane stuff. Look for air leaks.>cheaper/better material than rockwoolNot really, EPS has its advantages, but for your scenario there isn't really anything cheaper if you don't go into recycling garbage.
>>2973088Fiberglass or rockwool is a good sound insulator. They're almost identical at sound dampening The 5/8" fire rated drywall is the best sound insulator for the moneyThe weight is what stops soundYou could also or alternatively side the outside with cement siding and make sure all the gaps in the structure are filled with caulking or whatever
