How To Insulate Rim Joists With Batt Insulation

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Shannon from www.house-improvements.com shows you how to insulate rim joist ends in a basement using fiberglass batt insulation.
If you have questions about your home improvement projects, stop by the forum on our website, where Shannon will answer your questions in detail for free.
Website: www.house-improvements.com
Forums: www.house-improvements.com/for...
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Video © 2016 SKS Media. Videos produced by SKS Media (House-Improvements.com) are provided for informational purposes only. The information contained in the videos is intended to give general guidance to simplify DIY (do it yourself) projects. Because tools, products, materials, equipment, techniques, building codes and local regulations are constantly changing, SKS Media cannot and does not assume any responsibility or liability for the accuracy of the information contained therein. Further, SKS Media will not accept any claim for liability related to, but not limited to, omissions, errors, injury, damage or the outcome of any project. It is the responsibility of the viewer to ensure compliance with all applicable laws, rules, codes and regulations for a project. The viewer must always take proper safety precautions and exercise caution when taking on any project. If there are any questions or doubt in regards to the element of a project, please consult with a licensed professional. SKS Media conducts all matters in accordance with the laws of Saskatchewan, Canada.

[@tracyacres7937]

Going to insulate my garage, and also need to fill gaps at floor joists in my basement where wasps got in and built a huge nest. I stumbled on your videos, and find them really helpful..especially for our Canadian temperatures. You are easy to listen to, to the point, and cover it all off. Your camera person is good and steady too! Thanks and great job!

[@LevRex420]

He's from Alberta, so the content is very Canadian weather focused, it's great.

[@johntheriault7520]

Very friendly to listen to and to follow your very methodical and clear directions. Thanks

[@jimlum9127]

Thanks for the how to demo. This is great for me to upgrade my basement. Good clear explanation without too much personality insert. Professional down to earth.

[@Zamicol]

I love your videos. Thank you for all your hard work. You're a great teacher.

[@donaldwalker3801]

Great video, thanks for the excellent info given in a clear concise manner that can be understood, I am a fan! Thank you!

[@ikust007]

Cannot tell you how much you helped me. Thank you !

[@felipeborrero4020]

you make it look so easy. Even if I don't do it myself I can now tell someone what to do. I've learned so much from your videos. thanks I know how much work it is to produce, edit and upload. so just wanted to let you know I'm watching.

[@HouseImprovements]

Thanks ,we try our best !

[@jamescardinal4439]

This guy does not make this look easy trust ne

[@joelthomas4294]

Thanks was wondering how to do this in my basement, I have a lot of insulation left from ceiling project and will be doing this early fall. 🤙

[@FrizzellCorey]

Thanks for this and the rest of your videos. Very concise, informative and helpful! 👍🏼

[@ozielvillarreal9653]

Great video! I just happen to be planning on doing similar insulation on my garage. Your tips are very good. Thanks

[@chrisdraper1976]

Great videos. Straight to the point. Real conditions

[@smirkinatu5512]

Thank you for recording and posting this valuable educational video.

[@mbrown2886]

Thank You for Showing How to Insultate Rim Joist areas in the Basement

[@SuperFunny65]

Really clean job. Thanks for posting.

[@markhamgarden3592]

THAT WAS REALLY HELPFUL

[@petemiller519]

Thanks for the video. I think I am going to look into the spray foam kit. I did this on my last house, but it had TJI's which made it even more complicated. I hate that black stuff...good idea to have a rag with paint thinner near by. Cheers from BC

[@notrut]

Great tips video, Thanks ... (and no screaming guitar music!) Keith, in NE England.

[@lizamillenium1288]

Thx for all your videos.bur great at teaching. Really really appreciate you. Thanks again

[@Diva2670]

Love your videos. I am a single, mom homeowner and your videos are the perfect learning platform for me!

[@HouseImprovements]

+Nita2670 glad to hear that

[@tywheeler7131]

well there super chief, this is a quality instructional video.

[@frankhagar4651]

Good work like always

[@brucepilcher87]

Thanks just what I was looking for!

[@bdawg8907]

I used that method to seal rim joists. After 15 years so so we noticed some cold spots in an upstairs bedroom and then in a corner of a basement room. Removed some suspended ceiling tiles downstairs and found that the acoustical sealant hardened over time and the plastic pulled away letting air get through ever so slightly,pulled back the plastic and insulation and found about an inch of ice on the rim joists , what a mess. Ended up pulling ceiling tiles around the entire perimeter and found more spots where the plastic separated. Ended up pulling down all the plastic and removing the insulation… cleaned out mold spots and dried the rim joists then shot it all with spray foam instead. Spray foam is way more expensive but far quicker and less mess. If I were doing it from scratch I’d probably do a combination of spray foam and rigid foam to cut the costs a bit but give an excellent seal.

[@macsausage87]

Thanks for the video!

[@aboveallholidaylighting9305]

Thanks Shannon.

[@AdrianJayeOnline]

nice vid, not sure why 3 dislikes... I dont know some people are crazy really nice neat work, all your vid are cool , you rock dude

[@fatcapital88]

great video... super helpful... thank you!

[@duncanwilliams4837]

Great video, thanks so much👍

[@bosse641]

Good job.

[@toddrussell7616]

Thank you!

[@plantagominor722]

Sure, but can we talk about how soothing this guy's voice is?

[@chrisparsons3141]

If I was homeless I'd still watch.

[@ChiralSpirals]

I enjoyed it.

[@songofthemist7443]

thank you, very helpful

[@HouseImprovements]

glad to help

[@chuckgoodman3828]

I chalked and used foam board and foam insulation on my rim joist areas. I’m very pleased with the results.

[@peterbergeris6510]

Did you use 6 poly over your rim install? Is it necessary?

[@canuckfixit7722]

@@peterbergeris6510 No, don't lay poly over XPS. Doing so will trap moisture if given the chance. XPS doesn't need that because it is non- permeable.

[@peterbergeris6510]

Didn't Home improvement video use 6 poly over rigid insulation in rim joists because it was an inside wall?

[@peterbergeris6510]

Sorry, he used batt insulation n not rigid.

[@lmcgbaj]

BTW, fantastic reviews. Very good.

[@HouseImprovements]

Thanks.

[@geojor]

good work, thank you ...

[@HouseImprovements]

Thanks

[@abrahamghannam2137]

Thanks👍

[@coreyhondzinski8097]

Hmmm, I was told by an inspector and a contractor to pull the pink fiberglass insulation out of my basement box sills and use closed cell foam insulation. It doesn't prevent water vapor from condensing and accumulating, causing damage over time. Go with rigid pink foam or spray foam (I picked the pink stuff)

[@peterbergeris6510]

Roxul is water proof and will not burn.

[@ravrupana8136]

Can you also post a video doing insulation and drywall into the garage please i have plan to do my garage , your all the videos are very useful sir...

[@Klimovitsky]

great video.

[@HouseImprovements]

thanks

[@Chris_at_Home]

Great video. I’m just finishing a small duplex with an owner until in Alaska. I built boule stud 2x4 walls with a 2x8 top plate. The exterior walls have R40 closed cell foam. . I did the ceilings with R38 on top of R21 between the ceiling joists. I live on a south facing hill and have daylight basements wrapped in 4” of foam. Last winter was one of the coldest here with a week of -30s. We only burned about 500 gallons of oil heating 3000 sqft.

[@RandyD1972]

Thanks for making this video. This is another project that I'll have to add to my list when refinishing the basement of my 1961 bungalow. #itneverends Looks like a lot of work and I hope to find a video of your rigid foam technique before I commit to which method I'll use.

[@HouseImprovements]

kzbin.infovideos?view_as=public

[@brettbarager9101]

Everything you say makes perfect sense. Personally I would never attempt this cause I already know I would get more adhesive on me than where it is supposed to go! Lol

[@350munrohome]

Love your work, must be cold where you are, most houses out my way have no insulation at all.

[@DIYBuilds]

+350munro Ahh the good old insulated Canadian basement

[@HouseImprovements]

+350munro Canada, eh. Temp can dip down to -40 -ish in winter on extreme days.

[@paulmoffat9306]

Mineral Spirits is the solvent to remove acoustic sealant.

[@nobimeatalknobimeatalk1944]

cool one man

[@AdrianJayeOnline]

damn nice stapler !

[@Heffbomb]

Wow that looks like a pain in the butt. Worth it to spring for foam board.

[@northboundinsulation7355]

Acoustic sealant not required. It is definitely a bonus but you can use the red/blue sheathing tape instead. Quick pro tip. The black acoustic sealant comes off the skin with a little margerine.

[@poetnk]

tuck tape often comes loose over time as it dries, or it might be difficult to stick it to a dusty basement joist - as with any adhesive tape. Caulk will always be pliable and will always create that "air tight" seal, even with time - this is also why he staples it. You can staple tuck tape, but then you're creating tiny holes for air to get through with each staple. Staple caulk and it's self-sealing.

[@skiprope536]

I think you need to drive a few more staples in that bay.

[@susanprice6264]

Hi Shannon, I have an unfinished basement in a house built in the 1930's. This video clearly shows how to add insulation between the joists but how would I insulate the area along the walls that run perpendicular to the joists? How would I secure batts and vapour barrier? I want to insulate where concrete and joists meet on all 4 walls. Thanks

[@HouseImprovements]

please use my forum for your question. www.house-improvements.com/forums/

[@ericgoudysr.2746]

Good

[@cz3chmonkey]

Nice camera and work. How can you tell if the person that built the basement didn't seal the poly very well? Liquid water on drywall?

[@mikhailjoukov3910]

Hey Shannon! Love your videos. I am renovating my basement suite and ended up doing something similar with rim joist spaces and this video just came up on my feed. I used accousti-seal all around the seams of the rim joist to air seal, then stuffed it with rockwool. Do you think that is sufficient? By the way, anyone that gets accousti-seal or that roof tar on them, try using lysol or baby wipes. I find that they work very well to get that stuff off quick.

[@HouseImprovements]

That will be better air sealed then without the acoustical but would not pass code on its own.

[@willg4802]

Wow, his eyes!

[@RichNSmoothified]

freaky

[@henryhenry5897]

If there is only one space in a house that should get sprayfoam and not fiberglass, rimjoist would be it. Nice vid you defently do it right I just see fiberglass fail on a daily bases and especially in rim joist.

[@ianholmquist8492]

I run a sprayfoam rig in Vermont. Treating the basement sill with closed-cell foam is definitely the the most cost effective thermal boundary upgrade one can do to a home. Just make sure there is enough air for all combustion appliances.

[@gasmanrm]

ive never seen this method used,would certainly be time consuming.most new subdivisions just staple in place without sealant,perhaps use red sheathing tape on bottom. good video as usual

[@HouseImprovements]

stapled in place would never pass code. At least not here

[@consumersgasman8376]

thats all they do in York Region

[@ICarriere21]

@@HouseImprovements been insulating 6 years in all of SW ontario and literally I'd quit if I had to do this. a few staples and that's it

[@odellpineda9149]

do you have a video on how to level basement ceiling?

[@vitaliy3434]

helpfull!

[@cobrakai2872]

I did this in my old house. Was planning to do in my new house but the inspector said I needed to cover with drywall. Poly or kraft faced insul is flammable. I need to do something since I'm getting condensation on the top of the exposed concrete, under the fiberglass insulation

[@HouseImprovements]

Thats a new one to me, poly is not generally worried about left exposed in rim joist spaces? Ask about using rigid foam sealed with canned foam and ten covered with Roxul insulation (it is fire resistant)

[@cobrakai2872]

@@HouseImprovements I used 1" foamboard then sealed with spray foam. Brought batt insulation out to the plan of the drywall. In the winter when I removed the batt to inspect, there was moisture and frost on the joists and concrete sill. Since I live here now, I may just do what you show with some minor mods since drywall is up and painted. Instead of poly, I have this plastic that will breath vapor when the RH >60%. Will feel better about not locking in vapor if any is present. Thanks for reply.

[@rogerwhiting9310]

I think your inspector doesnt know what he is doing

[@blehssed]

Under the Ontario building code you need to have foamed plastics covered in most applications, usually plywood or drywall.

[@HouseImprovements]

Yes in many places you do need to have it protected from fire. Fire rated ceiling or drywall ceiling would do it for most places

[@blehssed]

@@HouseImprovements I've used your videos as a great learning tool! Appreciate your response.

[@rwirth3680]

How does this affect the floor above it? It appears that the floor above would be on the cold side of the insulation

[@mtdewchallenger]

Excellent work ... tedious job. Is there instruction on filling the long one behind you that is already poly-ed in ?

[@HouseImprovements]

Those can be different from home to home. Many times there is no space to actually get in-between the last two to do anything or just enough to get your hand in to place batt insulation. You just have to do the best you can.

[@johnandrews7922]

Great video. If i am using a frothpack to air seal the rim joists do i still need to put polly up.

[@HouseImprovements]

If it is a closed cell foam and at least 2" thick you should not need a separate air/vapour barrier.

[@andrewmartin9440]

Thanks Shannon. Been watching a lot of your videos. Where are you out of?

[@HouseImprovements]

+Andrew Martin Canada, eh!

[@londononcan]

hi Shannon i found mold in the insulation at one wall in the basement, at the sill plate/Rim Joists area. the patio door is just above this wall, and the wood deck is at the outside of this wall just leveled with the Rim Joists. what is your explanation and advise?

[@HouseImprovements]

please use my forum. www.house-improvements.com/forums/

[@canuckfixit7722]

I did this technique vary carefully and as Shannon said, you get that black sealant all over the place. Unfortunately, in the four "test" bays I did this, I got lots of condensation on the inside of the plastic in the hottest/humidest part of the summer, despite my best effort to seal the bay up thoroughly. Tearing it all out now and going with XPS sealed with foam around the gaps.

[@kw6713a]

What's your climate if you don't mind me asking? I'm seeing Canadians do vapor barrier facing the interior (as showing in video) and southerners do vapor barrier facing the exterior (usually foam board or spray). I guess the issue would be where the warmest air generally will be. I live in wny and most months the basement will be warmer than the exterior. NYS seems to advise 2 inches spray foam, of course, that's the most expensive way to do this.

[@canuckfixit7722]

@@kw6713a Not too different from western NY. Cold winters with hot and humid summers. Vapor barriers in the basement on the "warm in winter" side typically cause all sorts of condensation on the inside of the 6 mil plastic during the hottest and humid weather of July and August. Only dries out in the fall. The new procedure is to NOT install any vapour barrier on the warm side and DO install Typar next to the foundation. Or, just infill the cavities with spray foam.

[@kw6713a]

@@canuckfixit7722 thanks man, that's very helpful to know. What do you think of 3" XPS board inside the cavity, spray foamed around the edges as a substitute for the spray foam kit? Then a drywall piece for fire retardant. Seems less costly though more time consuming.

[@canuckfixit7722]

@@kw6713a Correct! That's exactly what I did: To match the R20 in my main walls, I used two pieces of 1.5in XPS (extruded, not expanded). Each piece cut a little smaller than the cavity, inserted , centered with a temporary brace then foamed around the edges. Let that one cure, then trimmed off excess foam and repeated for the next piece. No adhesive needed. To hold the drywall covers in place, I cut 0.5 x 0.5 in pieces of wood placed vertically on each side then brad-nailed them in. If done right, the drywall will be flush with the sill plate or proud of the sill plate in which case cut it wider and screw to the side of the sill plate. This does take time and the thick XPS sheets can get expensive.

[@kw6713a]

@@canuckfixit7722 thanks a lot, that makes a ton of sense and a load off my mind. All doable and should be within budget. One minor question, does the drywall have to be flush up to the foam board or should it be flush to the edge of the sill plate?

[@NoRoads2AllRoads]

hi +HouseImprovements ... if we have insulated with 2 or 3 inch XPS, do we still need the poly? I am under impression we dont...

[@cyberpunkspike]

don't

[@twlandes]

I watched a how-to vid showing foam board being glued into the rim joist space first and it was cut undersized so that spray foam could be sprayed in around the edges for added stability. After that they installed paper-backed insulation into the space to finish it up. The vid maker said to do this because fiberglass insulation in direct contact with the wood surface could become wet due to condensation which can cause mildew and later wood rot. Your thoughts on this?

[@HouseImprovements]

If you are in an area with a air/vapour barrier requirement and you didi not use it or install it properly then that could happen, yes.

[@christopherpavlicas]

Use rigid foam cut 1/4in short height and width and secure with foamboard adhesive and then use spray foam to fill the 1/4in gap all the way around. If you want additional R-Value, you can simply add some unfaced batt insulation to fill the remaining space in the rim joist. You will not have any mildue/moisture issues with the batt insulation if you do it this way.

[@beebob1279]

What about basement moisture? My home has cinder block up into that space. Suggestions? Thanks

[@Tzarsio]

based on what I've seen around, same techniques but your foundation have to be sealed from the outside

[@Shawn855]

Previous owners had fiberglass inside the rim joist, and spray foam behind it acting as a vapour barrer. It trapped the moisture, making the insulation damp, csusing the wood around it to rot. Im now replacing my sill plate, joists, sub floor, and sheathing. Should only use closed cell spray foam in rim joist area. Nothing else.

[@iowaman83]

Can you please put a link to what caulk you used?

[@reddog418]

Save time. Use Rockwool. It will create a similar air barrier. Also FYI building science has determined that latex primer has the same vapor resistance as plastic. Except vapor is nothing compared to air movement.

[@HouseImprovements]

Yes really restricting the air movement is as important.

[@peterbergeris6510]

I bought rock wool for 2x6 r23. I only had to cut once. I don't think I need 6 poly to cover since it's a comfort batt.

[@Chris_at_Home]

If you don’t put in a vapor barrier you will get condensation in you insulation and make it worthless. I live in Alaska and I have been in peoples basements where to batt insulation is damp. I cut closed cell rigid foam board about 1/2” smaller than the opening and then foam the gap using one of those $50 foam guns the cans screw too.

[@peterbergeris6510]

@@Chris_at_Home roxul is water proof. If water gets on it , it will not even reach the middle of the batt. This old house with Tom Silva put 1x3s horizontal n vertical against rigid insulation. He told homeowner he could install rock n didn't mention barrier. In warmer states no barrier needed. But zones 4,5 and above it's required.

[@simonewentzel64]

Hey Shannon, I know this video is older but I need your advice. I live in Calgary, and have frost on my basement walls as well as damp walls behind the fiberglass. I had a basement expert come today, they said my rim joists are not insulated which leaks cold air into the basement and that's why my walls are wet and when the frost thaws it drips on my floor. She recommended that I get them to spray foam the rim joists and go 2 feet down in order to ensure that I have a proper seal. This will reduce cold air from coming in and causing the frost. She also said my humidity levels are too high (45%) and that, combined with the rim joists not being insulated, is causing my issues. Would you agree?

[@HouseImprovements]

There could be a number of factors ,including that one. We could discuss it more if you post this question on my forum. www.house-improvements.com/forums/

[@sweetcarefulheart]

The method you like, will you not be covering with VCL/vapour barrier?

[@HouseImprovements]

In my area it is allowed to be left that way if its well sealed.

[@marc7491]

We live in the mid-Atlantic states. Can we use just foam board cut to size and seal it around the edges with spray foam?

[@drsg9124]

yes

[@MrTooTechnical]

this method can work. but the foam method (in contact with the rim) is better. thanks

[@HouseImprovements]

+dave daved I would agree.

[@jameshindle740]

Could you use a piece of 1/2" or 1" foam board rather than the poly, to vapor seal the batt insulated space. I'm sure you have a video on this, but I just couldn't find it. 😊

[@HouseImprovements]

Most places will allow 2" foam to do that if its sealed. kzbin.info/aero/PLh0KqGKtX4oWcBaAyNet_W9UL0nfPS16F

[@TeslaBoy123]

In my home town plastic in basement walls are not allowed bcz basement concrete wall need ventilation around exterior walls

[@christiangeorge358]

What type of poly barrier do you sue? Regular 6mil? And how would you insulate the long gap under a gas fireplace above?

[@HouseImprovements]

It is not regular 6mil poly it is specially labeled for use as a air/vapour barrier. Please use our forum for other questions.www.house-improvements.com/forums/

[@chrisbain5748]

OK great vido but at the end you are talking about an unfinished basement can I ask what do you put in front of the rock salt as you covered the 2 inch hard foam board.

[@HouseImprovements]

The Roxul can be used in front of the foam to create a fire barrier between the interior of the home and the foam when the foam is not cover with a drywall finish.

[@lyndseythomas3063]

The Roxul would still require a vapour barrier on top of it, correct?

[@avenged06x]

Holy staples! lol

[@percyfaith11]

Acoustical sealant is very expensive too. $19.99 USD per tube at Amazon as of June, 2022.

[@HouseImprovements]

Its not expensive in stores here. Maybe $6 Canadian

[@percyfaith11]

@@HouseImprovements I'd better look around. Maybe drug companies are marketing it here.

[@mariomatejka]

What do you think about stuffing the cavity with an insulation that has been put in plastic bags (waste basket or shopping bag). No acoustical sealant needed.

[@MrTooTechnical]

+Mario Matejka funny. No, dont do that. that wont work.

[@HouseImprovements]

+Mario Matejka That will not work at all. The poly is to create a air/vapour barrier between the exterior and interior of the home.

[@celticstoneworks.construct4570]

curious to know how many tubes of sealent you use for them squares.

[@HouseImprovements]

Not exactly sure but I would guesstimate that you would use one tube for 20-30 of those joist spaces.

[@manuelsantiago6512]

No vapor barrier.. This will collect moisture.. Foam insulation directly to concrete then frame..

[@JohnMiller-oz7gv]

I've been in pest control for 30 years and have been in tens of 1000s of buildings, in every square inch of them. That's not an exaggeration. I would never do this unless I lived in a harsh winter environment.

[@HouseImprovements]

Required to be insulated and air/vapour barrier covered in many northern areas like Canada.

[@lmcgbaj]

Instead of the black acoustical caulking, can I use silicon?

[@HouseImprovements]

No

[@hectorneira8487]

Isn’t it easier to let you walk poly go 10 inches over the upper plate ? And just cut it to fit the space there ?

[@drtomasdds]

Hello all. Can anyone tell me if I can find Accoustical caulk at our local big box stores in the US? Can't seem to find it on websites. Thank you.

[@rozmyslrozmysl8881]

The author of the video is from Canada, they sell PL Acousti-Seal there in HomeDepot etc. Looks like they don't carry it in the US. www.homedepot.ca/en/home/p.pl-acousti-seal-vapour-barrier--sound-reduction-adhesive-300ml.1000409509.html

[@AngelRivera-gm7bx]

Can we do this with foam insulation? Thanks

[@crispychicken2743]

It's a better way . This is over kill. Locking in water , rot and bugs behind the insulation and plastic .

[@cliffBMRC]

I put roxul r19 against rim boards . Is it ok to put rigid 2 inch foam board over that sealed on edges as alternative. Great video. Thanks. Ds

[@HouseImprovements]

Go for it!

[@peterbergeris6510]

You can buy roxul for 2x6 r23 and cut once.

[@peterinbrat]

Why not use Celotex and Good Stuff?

[@tonyrollin402]

Hi Shannon i am getting ready to do my basement so I have a question so my basement walls are block wall so is it on to put up 6 mil Polly frame then insolate then a another layer of six meal poly over that then drywall ?

[@HouseImprovements]

Depending where you live and the codes there . In my area , yes. You need a moisture barrier ,insulation and a vapour barrier. Here is my playlists for basements.kzbin.info/aero/PLh0KqGKtX4oWcBaAyNet_W9UL0nfPS16F

[@contact3210]

A home inspection report recommended stapling R19 batting insulation into rim joists. As it was, there was no rigid foam secured against the wood. Is this acceptable? (I already stapled the batting insulation in place, against the wood, as the inspection recommended.)

[@HouseImprovements]

That is still ok.

[@kw6713a]

I suspect this matters by climate? Down south they seem to put the vapor barrier snug against the board (usually xps with sealing around).

[@pa.fishpreacher6166]

I have a few hot water pipes from the furnace running up thru those cavities, they are too hot to touch, if the insulation touches those is that okay?

[@HouseImprovements]

Check with your local HVAc shop but I would say if you used Roxul insulation in those spaces you should be ok.

[@Brando-_-440]

If we're not just gonna spray foam it professionally, I prefer using just a couple inches of rigid foam at the bottom where the concrete meets the wood sealed in with caulk and not covering that whole area. Seal all those cracks with caulk and then fill that shit in with batts. I have tested this with thermo and it does just as good and saves money cause you use way less rigid foam (30 bux for a 4x8 2in r10 is high as hell in my book). And I like caulk better than that messy Great Stuff any day.

[@HouseImprovements]

And i actually prefer the rigid myself so I do not have to deal with the poly. Your way is fine as long as the caulk you use sticks and stays stuck for years

[@simonsanderstein1241]

u r creating a serious, major problem with condensation and rot, by using this method

[@bodhisattva4eva]

@@simonsanderstein1241 the batt and poly method here? How so?

[@HighGear7445]

I used XPS but then covered it with mineral wool batts (ROXUL) for a fire barrier. Foam needs to be covered but fiberglass melts almost immediately and gives you no time to escape before toxic fumes overcome you.

[@ianscianablo8507]

Hi. I'm in upstate NY. Got an old house with stone foundation. Huge millipede infestation and drafty house. How best to insulate my basement ceiling? Hard to do with wires/cables all over. Got the oil burner down there too. Wouldn't the upstairs be warmer if the basement ceiling was insulated? How best to do this? Thank you!

[@realruggeddiy]

Can you post a link to a picture. One of us are from Plattsburgh NY. Ever hear of it?

[@davesilvia9711]

Stop your drafts

[@kw6713a]

Late to this party but I have a similar southern tier house. Isolating basement from climate control seems out of bounds given electrical, plumbing and HVAC units that are down there. Should try to keep it at 50 degrees to avoid freezing all that stuff, so it's not recommended to insulate the 1st floor from the basement in that case. Insulating the rim joist is proving complicated, though air sealing seems the most important thing to do.

[@tonyrollin402]

Hi