Green Building Tips for a School Bus RV Conversion Project

Hello all!

I am currently ripping out the interior of a school bus that I am converting to an RV to live and travel in. I am familiar with green building techniques for homes in various climate zones with standard wood framing, but am unfamiliar with the techniques for a Steel-frame, sheet-metal-enclosed building envelope. Seeking Help! 

The first step will be to seal all penetrations, windows and any seams or leaks with all-weather silicone caulk and sealant. Once the shell is sealed, I'm not sure how to deal with insulation, air and vapor barriers because I'm not sure if condensation will be an issue with the sheet metal exterior.

So, I am reaching out to you all for some insight/ideas for the following components. Keep in mind, I will have a small pellet stove for off-grid space heating that should keep the interior dry, and will have a small AC unit + fan that is run off of deep-cycle batteries with solar.

Best Practices Recommendations?

Insulation:

-Denim batt insulation or Eco spray foam: Which would you prefer? What are potential issues with moisture from the steel frame and sheet metal walls?

Air/Vapor barrier: Is this necessary in this type of enclosure? I will mostly be living in a heating-dominant climate, so the vapor barrier I'm familiar with is on the inside of the enclosure, in front of the insulation. Does this still work? 

I don't want moisture to get trapped behind the insulation against the sheet metal of the bus and cause any issues there, so I am seeking advice if any one has some insight, I would be truly grateful.

Thank you!

Jenna

Tags: RV, air, barrier, best, building, bus, comfort, conversion, green, insulation, More…metal, practices, seal, sheet, siding, studs, thermal, vapor, waterproofing

Views: 177

Reply to This

Replies to This Discussion

RV's always use foam due to they want to keep as much space as possible inside though generally they are sheets. With that a properly installed CC spray foam gives you the most bang for your buck & helps ensure your don't have moisture issues on the metal skin (make sure you talk to manufacturer reps - especially on prep / prime) & eliminates need of vapor barrier as it & the metal skin is one

I agree with Sean that closed cell spray foam is the way to go. Closed cell gives you R6 to R7 per inch, compared to about half that for open cell and fibrous insulation. Also, open cell is vapor permeable and you need at least 3 inches get an effective air barrier (maybe even more, can't find my reference).

Thanks for the advice! I was hoping to get away from the foam option to be more eco-friendly with the build, I have just about 600 square feet of wall, floor and ceiling area needing coverage, other options are so pricey!

Thermacork= $3,900

Roxul= $2,500 + rigid floor insulation

Spray foam= $800

Denim batts= $800 + need vapor barrier or some way of keeping condensation from building up + rigid floor insulation

Loose wool insulation= $560 +need vapor barrier or some way of keeping condensation from building up + rigid floor insulation

I hate having to use foam on this project, but it would definitely be cheap + easy. 

Any suggestions on how to make the wall assembly work with loose wool using netting or denim batts?

Thanks again!

RSS

Forum

Thoughts on EVs? Love em or hate em?

Started by Kyle Baker in General Forum. Last reply by David Butler 4 minutes ago. 3 Replies

Capillary break retrofit

Started by Paul Raymer in Best Practices. Last reply by Paul Raymer on Thursday. 3 Replies

Help with OpenStudio/EnergyPlus

Started by Kerry Haglund in General Forum. Last reply by Kerry Haglund on Thursday. 1 Reply

Insulating Chilled/Cold Water Lines

Started by Sean Wiens in HVAC. Last reply by Sean Wiens Jan 20. 10 Replies

What's the Most Profitable HVAC Job for Your Company?

Started by Wayne Melancon in HVAC. Last reply by bebelyn accessdoors Jan 16. 5 Replies

Looking for a Rater in Sacramento Area

Started by Brian A McFadden in BPI. Last reply by Building Performance Institute Jan 14. 1 Reply

Hydronic System Critique

Started by Sean Wiens in HVAC. Last reply by Sean Wiens Jan 14. 8 Replies

Latest Activity

David Butler replied to Kyle Baker's discussion Thoughts on EVs? Love em or hate em?
"@Kyle, I spotted an error in the article. You wrote: > Washington DC: <$0.10 per kWh…"
4 minutes ago
Sean Wiens replied to Kyle Baker's discussion Thoughts on EVs? Love em or hate em?
"If you are concerned about environmental footprint, then they make no sense in the USA at all…"
1 hour ago
Building Performance Institute liked Diane Chojnowski's group News & Announcements
2 hours ago
Building Performance Institute liked Diane Chojnowski's discussion Nominations open for Linda Wigington Leadership Award
2 hours ago
Building Performance Institute liked Diane Chojnowski's discussion Volunteer for HPC19
2 hours ago
Building Performance Institute liked Diane Chojnowski's discussion Building Performance Association December Newsletter
2 hours ago
Building Performance Institute liked Diane Chojnowski's discussion BPI Winter 2019 Performance Matters Newsletter
2 hours ago
Building Performance Institute liked Wayne Melancon's discussion What's the Most Profitable HVAC Job for Your Company?
2 hours ago
Building Performance Institute liked Building Performance Journal's blog post Dust-Control Strategies for Energy Upgrades
2 hours ago
Building Performance Institute liked Macie Melendez's blog post Re-introducing Myself as the Building Performance Journal’s Managing Editor
2 hours ago
Steve Kramer replied to Kyle Baker's discussion Thoughts on EVs? Love em or hate em?
"I think hydrogen fuel cell technology is where the future of clean and abundant energy is."
3 hours ago
Kyle Baker posted a discussion

Thoughts on EVs? Love em or hate em?

EVs are a bit of a controversial topic. Their environmental benefits post-assembly and…See More
3 hours ago

© 2020   Created by Building Performance Association   Powered by

Badges  |  Report an Issue  |  Terms of Service