Also - I just want to say - plaster dust - EEEEWWWWW!!!!! Thanks everyone.
Insulation
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Yankeegirl
- Settling in
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- Joined: Mon Aug 24, 2015 1:02 pm
- Location: Adirondack Mountains New York
Insulation
Need some advice please. We are currently doing demo in the living room - when we are ready to insulate I need to know what r value to use for bat insulation. Do I need a vapor barrier? I'm super tired lol and have no patience right now to google info. Any advice is truly appreciated.
Also - I just want to say - plaster dust - EEEEWWWWW!!!!! Thanks everyone.
Also - I just want to say - plaster dust - EEEEWWWWW!!!!! Thanks everyone.
Re: Insulation
There are plenty of target values for insulation.The first question though is what size is the framing? 2x4, 2x6, something different?
I just did a reno in a room in our 1907 cottage, the framing was actual 2x4, so I was dealing with 4" depth which basically limits you to insulation for framing (modern) that is 3 1/2 inches deep and at that point R13 is about the best you can get.
I strapped the walls to gain another 3/4 of an inch and used an R21 insulation that is only 5 1/2" deep....the same as the traditional R19 that is made for 2x6 framing.
There are also other things you can do to increase the R value, but I don't know if you want to get into layering different types of insulation...
As to vapor barrier, if you use kraft faced insulation, do NOT add a plastic vapor barrier and do your best to seal all seams, etc to make the insulation air tight. IF you choose to use unfaced batts, then you can skin the wall prior to finish (sheetrock?) with plastic sheeting or similar.
I just did a reno in a room in our 1907 cottage, the framing was actual 2x4, so I was dealing with 4" depth which basically limits you to insulation for framing (modern) that is 3 1/2 inches deep and at that point R13 is about the best you can get.
I strapped the walls to gain another 3/4 of an inch and used an R21 insulation that is only 5 1/2" deep....the same as the traditional R19 that is made for 2x6 framing.
There are also other things you can do to increase the R value, but I don't know if you want to get into layering different types of insulation...
As to vapor barrier, if you use kraft faced insulation, do NOT add a plastic vapor barrier and do your best to seal all seams, etc to make the insulation air tight. IF you choose to use unfaced batts, then you can skin the wall prior to finish (sheetrock?) with plastic sheeting or similar.
Etta says "WOOF"
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Yankeegirl
- Settling in
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- Joined: Mon Aug 24, 2015 1:02 pm
- Location: Adirondack Mountains New York
Re: Insulation
Thanks Skip!! I'm not sure how deep the space is but I will measure. On an outside wall does the paper side face out or in? I'm heading off to bed soon so that I'm ready for round 2 tomorrow. Thanks again!!
Re: Insulation
Paper faces in, generally the batts are sized for the stud bay (15 or 23 inches for 16 or 14 on center) and have paper 'flanges" that are stapled to the studs. This not only keeps them in place, but helps seal the cavity. Make sure you fill the bay but don't overly compress the insulation or it loses some of it's insulation properties. It needs the air in it to work. Also, I like to make the batt about 2" longer than the space in the bay to make sure I get a good seal at top and bottom. If you need to add material due to a larger stud bay (say 20" and you have 15" insulation) try to make it about 1" wider than needed to compress the joint between pieces and tape it if you can. Hope all that makes sense!
Etta says "WOOF"
Re: Insulation
I stopped buying faced stuff as my studs were everything but the correct spacing. You can remove the facing if you choose to go the plastic route
Mick...
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phil
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- Location: Near Vancouver BC
Re: Insulation
im using Polyisocyanurate: Rated at R6-6.5 per inch in my living room walls right now, you can read my thread for the details. Its a bit more time consuming as Im also cutting each panel to fit and installing with spray foam.
here's an article comparing the different foam insulations
http://www.ecohome.net/guide/polyisocya ... -learn-use
In most of my walls I've used roxul. Its cheap and its a pretty good noise barrier. It's nicer to install than the pink fiberglass stuff, less itchy.
I'm not fond of the fiberglass bats but they are still used a lot.
what R value you "need" is a loaded question that no one can answer accurately but considerations are your humidity, temperature range, and don't forget to compare the acoustical properties if you are trying to block sound as well as keep the heat in.
in my case I have lots of cars so I am also experimenting with green glue and special sound proof drywall so you can consider those options if you care about sound blocking. cost is another factor.
so without knowing more I'd pick roxul but your mileage may vary. you can cut it with an old handsaw and yes it should squeeze a bit to have a bit of compression in the fit. what I sometimes do is staple fishing line across the studs as I install it , just to keep it from falling out. especially if you need to join pieces as described earlier. the roxul has a "harder edge" which is marked this gives that edge a bit more stiffness to aid in compressing the batt without breaking it up. you'll see notes on the package.
there are pros and cons to the vapor barrier. Its there to keep the humidity from cooking and the shower etc, out of your insulation , if installed incorrectly or in buildings with wet walls that dont' have lots of overhang there is some concern of trapping water with the plastic and many buildings around me have been subject to walls that are wet and moldy inside due to the overuse of plastic so it's controversial. If your house has drywall most likely it also has some roof overhang. if the walls don't usually get rained on its a big help. don't install plastic against the shiplap side, just the drywall side if you use it.
some of the Polyisocyanurate Im using now has foil on both sides so you don't' need a vapor barrier as well. some of what I have has a paper backing on both sides. You;d have to check what's available. the roxul is fast if you want to get it buttoned up.
myself I' wouldn't use fiberglass, because it's itchy and I think the roxul is comparable in price and R value and it's a better sound blocker. it's heavier than the fiberglass.
I just opened my walls too so I know about plaster dust. the thing to be most wary of is the dust from old drywll filler , it often contains asbestos. i had a real run around to get rid of my old drywall and ceiling tiles and plaster and had to get testing done before I could dump it. Just because it's plaster doesn't necessarily mean it doesn't have the old filler with asbestos but anyway, wear a mask at least. 100 year old mouse and spider poo probably isn't the best stuff for you either.
the canned spray foam is good to have onhand. Maybe dont' use it for wiring unless you are sure it won't hur the wire insulation but if you have holes from old knob and tube and things like that its quick and easy and those holes can spend a lot of heat. you could put putty made for electrical wiring holes in the holes that your romex runs through.
and before you close up, do you want any more wiring? how about network or cable? or wires to windows for security? no better time to run the wires in even if it's just to a coil in the basement to be finished up later.
new codes call for plastc boots over electrical and I used sheets of putty that are like plasticene , that's again for sound. If you dont' use the boots just be aware that it's common to get little drafts around the outlets, they are small but these things add up.
if you can see hairline cracks of light , those are areas of concern, even just a thin crack can do a lot so try to close up any you can find. I bet you can find a few big knot holes etc. try not to seal the outer wall too well though, If water does find it's way in you don't want to create a terrarium in there.
Phil
here's an article comparing the different foam insulations
http://www.ecohome.net/guide/polyisocya ... -learn-use
In most of my walls I've used roxul. Its cheap and its a pretty good noise barrier. It's nicer to install than the pink fiberglass stuff, less itchy.
I'm not fond of the fiberglass bats but they are still used a lot.
what R value you "need" is a loaded question that no one can answer accurately but considerations are your humidity, temperature range, and don't forget to compare the acoustical properties if you are trying to block sound as well as keep the heat in.
in my case I have lots of cars so I am also experimenting with green glue and special sound proof drywall so you can consider those options if you care about sound blocking. cost is another factor.
so without knowing more I'd pick roxul but your mileage may vary. you can cut it with an old handsaw and yes it should squeeze a bit to have a bit of compression in the fit. what I sometimes do is staple fishing line across the studs as I install it , just to keep it from falling out. especially if you need to join pieces as described earlier. the roxul has a "harder edge" which is marked this gives that edge a bit more stiffness to aid in compressing the batt without breaking it up. you'll see notes on the package.
there are pros and cons to the vapor barrier. Its there to keep the humidity from cooking and the shower etc, out of your insulation , if installed incorrectly or in buildings with wet walls that dont' have lots of overhang there is some concern of trapping water with the plastic and many buildings around me have been subject to walls that are wet and moldy inside due to the overuse of plastic so it's controversial. If your house has drywall most likely it also has some roof overhang. if the walls don't usually get rained on its a big help. don't install plastic against the shiplap side, just the drywall side if you use it.
some of the Polyisocyanurate Im using now has foil on both sides so you don't' need a vapor barrier as well. some of what I have has a paper backing on both sides. You;d have to check what's available. the roxul is fast if you want to get it buttoned up.
myself I' wouldn't use fiberglass, because it's itchy and I think the roxul is comparable in price and R value and it's a better sound blocker. it's heavier than the fiberglass.
I just opened my walls too so I know about plaster dust. the thing to be most wary of is the dust from old drywll filler , it often contains asbestos. i had a real run around to get rid of my old drywall and ceiling tiles and plaster and had to get testing done before I could dump it. Just because it's plaster doesn't necessarily mean it doesn't have the old filler with asbestos but anyway, wear a mask at least. 100 year old mouse and spider poo probably isn't the best stuff for you either.
the canned spray foam is good to have onhand. Maybe dont' use it for wiring unless you are sure it won't hur the wire insulation but if you have holes from old knob and tube and things like that its quick and easy and those holes can spend a lot of heat. you could put putty made for electrical wiring holes in the holes that your romex runs through.
and before you close up, do you want any more wiring? how about network or cable? or wires to windows for security? no better time to run the wires in even if it's just to a coil in the basement to be finished up later.
new codes call for plastc boots over electrical and I used sheets of putty that are like plasticene , that's again for sound. If you dont' use the boots just be aware that it's common to get little drafts around the outlets, they are small but these things add up.
if you can see hairline cracks of light , those are areas of concern, even just a thin crack can do a lot so try to close up any you can find. I bet you can find a few big knot holes etc. try not to seal the outer wall too well though, If water does find it's way in you don't want to create a terrarium in there.
Phil