Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×


Reply
 
Thread Tools Display Modes
 
Old 09-03-2020, 04:22 AM   #1
Mini-Skoolie
 
Join Date: Jun 2020
Location: Baltimore, MD
Posts: 36
Engine: MBE926210
Rated Cap: 31
Subfloor inquires

So I've been watching a few videos about subfloor installation; people often use insulation in-between 2*4s on the base. Looking in the comments, people who do construction keep saying that's not the way to go; I'm getting the implication that laying insulation and glueing the plywood subfloor to it is the way to go. Any guidance I can receive from you all? I'm not quite at that step yet, but I'm close and I just want to know the right way to do it. Also, recommended this of insulation and subfloor would be appreciated. Thanks!

Choc Lesnar is offline   Reply With Quote
Old 09-03-2020, 06:34 AM   #2
Bus Geek
 
musigenesis's Avatar
 
Join Date: Jan 2019
Location: Philadelphia
Posts: 6,992
Year: 2003
Coachwork: International
Chassis: CE 300
Engine: DT466e
Rated Cap: 65C-43A
From a thermodynamics perspective, you can't do better than a "floating" floor, which is just XPS foam board (or other kind of foam like EPS or polyiso, but these generally have a lower PSI rating) glued to the steel floor and a layer of thick plywood glued on top. Wood has a thermal conductivity about 5 times greater than XPS, so you want your floor (and walls and ceiling, for that matter) to be as much foam and as little wood as possible, and a floating floor is as good as it gets since it's all foam.

XPS is probably the best for this at a typical 20 PSI, but other types of foam can approach or exceed this value - you just want to make sure you're using a material with good compression resistance. And you need solid plywood on top to spread out the load (aka reduce the pressure), since a 100-pound ballerina on pointe would be far too much for the foam to support on its own.
__________________
Rusty 87 build thread
musigenesis is offline   Reply With Quote
Old 09-03-2020, 08:12 AM   #3
Mini-Skoolie
 
Join Date: Jun 2020
Location: Baltimore, MD
Posts: 36
Engine: MBE926210
Rated Cap: 31
Quote:
Originally Posted by musigenesis View Post
From a thermodynamics perspective, you can't do better than a "floating" floor, which is just XPS foam board (or other kind of foam like EPS or polyiso, but these generally have a lower PSI rating) glued to the steel floor and a layer of thick plywood glued on top. Wood has a thermal conductivity about 5 times greater than XPS, so you want your floor (and walls and ceiling, for that matter) to be as much foam and as little wood as possible, and a floating floor is as good as it gets since it's all foam.

XPS is probably the best for this at a typical 20 PSI, but other types of foam can approach or exceed this value - you just want to make sure you're using a material with good compression resistance. And you need solid plywood on top to spread out the load (aka reduce the pressure), since a 100-pound ballerina on pointe would be far too much for the foam to support on its own.
Is there any specific type of plywood you would recommend?
Choc Lesnar is offline   Reply With Quote
Old 09-03-2020, 08:29 AM   #4
Bus Geek
 
musigenesis's Avatar
 
Join Date: Jan 2019
Location: Philadelphia
Posts: 6,992
Year: 2003
Coachwork: International
Chassis: CE 300
Engine: DT466e
Rated Cap: 65C-43A
Quote:
Originally Posted by Choc Lesnar View Post
Is there any specific type of plywood you would recommend?
Something like this: https://www.homedepot.com/p/23-32-in...5189/100003769. T&G is very good for a floating floor since it keeps the edges flush, which is important when you don't have any joists to screw the edges into.

I would avoid OSB since it doesn't handle getting wet as well as plywood does (neither is waterproof but plywood goes back to normal after it dries out, while OSB is permanently damaged even after it dries out). It's a lot cheaper per sheet but you only end up saving like a $150 or so for a whole floor, which is a drop in the bus bucket IMO.

I would also avoid cheap plywood from Craigslist from a guy who acquires crates used to transport juice concentrate from South America and disassembles them. If you think that's oddly specific advice, you're right.
__________________
Rusty 87 build thread
musigenesis is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Featured Campgrounds

Reviews provided by

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 02:24 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2024, vBulletin Solutions, Inc.