# Basement build - starting with better rim joist insulation **URL:** \ **Category:** NYSpeed Off Topic\ **Created:** [September 8, 2014, 11:24am UTC](https://forums.speedlife.net/t/basement-build-starting-with-better-rim-joist-insulation/270524 "2014-09-08T11:24:26Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![neonglh](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/neonglh/32/4951_2.png) [@neonglh](https://forums.speedlife.net/u/neonglh)\ **Post date:** [September 8, 2014, 11:24am UTC](https://forums.speedlife.net/t/basement-build-starting-with-better-rim-joist-insulation/270524/1 "2014-09-08T11:24:26Z")
I have approximatly 1,100 sq. ft. of unfinished basement. I am lucky that it is both dry and radon free. I use the majority of it for laundry and storage, and then the rest of it is my workout room. I am planning out finishing the walls over the next year or so, but I started with a basic, and smart project, insulating the rim joists. When I bought the house all of the rim joists had R-13 fiberglass insulation stuffed in, which is better than nothing, but not really ideal anymore. Here is what I am working with: A shot of the workout room wall ![https://farm4.staticflickr.com/3864/14611891212_22e1e35232_b.jpg](https://farm4.staticflickr.com/3864/14611891212_22e1e35232_b.jpg) The old insulation ![https://farm4.staticflickr.com/3875/14425811748_fb56ff84b7_b.jpg](https://farm4.staticflickr.com/3875/14425811748_fb56ff84b7_b.jpg) Insulation removed ![https://farm4.staticflickr.com/3910/14632417163_cda192a456_b.jpg](https://farm4.staticflickr.com/3910/14632417163_cda192a456_b.jpg) Look at the dark stains on the fiberglass, that is all from airflow coming through the rim joists into the house ![https://farm3.staticflickr.com/2909/14425812038_f1461cc1b6_b.jpg](https://farm3.staticflickr.com/2909/14425812038_f1461cc1b6_b.jpg) I cleaned up each opening, cut the 9.5 x 14.5 pieces of R-10, 2" thick rigid foam out for each one, and then used Great Stuff spray form to seal around the edges. The final result is an air-tight seal that will keep any outside air from entering the basement walls via the rim joists. I can now put in fiberglass insulation over these openings once I finish the walls. I will likely do R-13, but R-19 is another option. ![https://farm4.staticflickr.com/3887/15181162285_4036c4685a_b.jpg](https://farm4.staticflickr.com/3887/15181162285_4036c4685a_b.jpg) I did one wall so far, so 5 walls to go. My future plans are 2" rigid foam on the exterior walls, followed up by a traditional 2x4 stud wall to run electrical and drywall. It will make the space approximately 6" smaller on each wall, but it should be a much cozier space. :tup: ---
**Author:** ![ubengineering](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/ubengineering/32/5171_2.png) [@ubengineering](https://forums.speedlife.net/u/ubengineering)\ **Post date:** [September 8, 2014, 11:36am UTC](https://forums.speedlife.net/t/basement-build-starting-with-better-rim-joist-insulation/270524/2 "2014-09-08T11:36:14Z")
Looks good, def use this as an example/inspiration. ---
**Author:** ![jimmyfloyd](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/jimmyfloyd/32/3077_2.png) [@jimmyfloyd](https://forums.speedlife.net/u/jimmyfloyd)\ **Post date:** [September 16, 2014, 1:37pm UTC](https://forums.speedlife.net/t/basement-build-starting-with-better-rim-joist-insulation/270524/3 "2014-09-16T13:37:38Z")
Are you going to place the rigid foam on the wall, leave a gap, or use a vapor barrier? Good stuff so far. I removed the R13 from my basement this summer, and haven’t replaced it yet. Did you use anything but the spray foam to hold the foam board in? ---
**Author:** ![tpgsr](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/tpgsr/32/7374_2.png) [@tpgsr](https://forums.speedlife.net/u/tpgsr)\ **Post date:** [September 16, 2014, 5:36pm UTC](https://forums.speedlife.net/t/basement-build-starting-with-better-rim-joist-insulation/270524/4 "2014-09-16T17:36:20Z")
I have a very large basement project upcoming. And a kitchen, and two bathrooms, and… I will make a thread for it. ANYHOW, What is he ceiling height in your basement? ---
**Author:** ![rugsr](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/rugsr/32/7474_2.png) [@rugsr](https://forums.speedlife.net/u/rugsr)\ **Post date:** [September 16, 2014, 8:10pm UTC](https://forums.speedlife.net/t/basement-build-starting-with-better-rim-joist-insulation/270524/5 "2014-09-16T20:10:49Z")
Completing a basement project right now…i should make a thread GL ---
**Author:** ![JDMSIR](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/jdmsir/32/7376_2.png) [@JDMSIR](https://forums.speedlife.net/u/JDMSIR)\ **Post date:** [September 17, 2014, 4:25am UTC](https://forums.speedlife.net/t/basement-build-starting-with-better-rim-joist-insulation/270524/6 "2014-09-17T04:25:03Z")
Doing my rim joist as well, I am buying a 2 part spray foam that covers 600 linear feet. Air tight, easier then cutting foam. Did you look into that at all? ---
**Author:** ![neonglh](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/neonglh/32/4951_2.png) [@neonglh](https://forums.speedlife.net/u/neonglh)\ **Post date:** [September 17, 2014, 7:00am UTC](https://forums.speedlife.net/t/basement-build-starting-with-better-rim-joist-insulation/270524/7 "2014-09-17T07:00:56Z")
> [@jimmyfloyd](#): > > Are you going to place the rigid foam on the wall, leave a gap, or use a vapor barrier? > > Good stuff so far. I removed the R13 from my basement this summer, and haven’t replaced it yet. Did you use anything but the spray foam to hold the foam board in? I only used the spray foam to hold in the board. I cut them to size within 1/8", so most of them I had to pound in to get into the space. The foam definitely tightened up the few that went in loose though. They are all solid and sturdy now. I am going to put 2" rigid foam on the wall as well. I am not using a vapor barrier or leaving a gap. I am using this 2x4 wall method, sans the extra fiberglass insulation between the studs: > **[How to Finish a Basement Wall](https://www.familyhandyman.com/project/how-to-finish-a-foundation-wall/)** > > For a fraction of the cost of an addition, you can convert basement space to living space. We'll show you how to finish a basement wall. > [@tpgsr](#): > > ANYHOW, What is he ceiling height in your basement? I can’t think of the measurement at the moment. It is less than 8’, but more than 7’. I can do jumping jacks down there when I work out, but I have to be careful to not hit my fingers. > [@JDMSIR](#): > > Doing my rim joist as well, I am buying a 2 part spray foam that covers 600 linear feet. Air tight, easier then cutting foam. Did you look into that at all? I did, but this will do the same job, at way cheaper. I can do my entire basement for around $100 with this method. It is a ton of work cutting out all of the slightly different sizes though, and there are a few openings that have wiring, ducting, etc…, so if you have the money to spend, the spray foam is probably a way better option. ---
**Author:** ![LUKE\_L](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/luke_l/32/7462_2.png) [@LUKE\_L](https://forums.speedlife.net/u/LUKE_L)\ **Post date:** [September 17, 2014, 7:43am UTC](https://forums.speedlife.net/t/basement-build-starting-with-better-rim-joist-insulation/270524/8 "2014-09-17T07:43:37Z")
Looks great so far!!! ---
**Author:** ![juicedz4](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/juicedz4/32/5051_2.png) [@juicedz4](https://forums.speedlife.net/u/juicedz4)\ **Post date:** [September 17, 2014, 12:46pm UTC](https://forums.speedlife.net/t/basement-build-starting-with-better-rim-joist-insulation/270524/9 "2014-09-17T12:46:34Z")
Cool shelf bro. Dan