Reply
 
Thread Tools Display Modes
 
Old 02-12-2019, 01:06 AM   #1
Mini-Skoolie
 
Join Date: Nov 2015
Location: Colorado
Posts: 10
Year: 2003
Coachwork: Thomas
Chassis: Saf-T-Linerģ HDX
Engine: ER3126E275
Question Sub-floor fastening

I just pulled all the wood flooring out of my bus, it is down to the bare steel. No rust at all thank goodness! welded closed all the bolt holes and put two coats of rustoleum down. Now getting ready to put in a sub floor of 1x2's 16 inches on center so I can insulate under the new wood floor. The question is what would be the best way of fastening the 1x2's to the steel floor?
772ark is offline   Reply With Quote
Old 04-07-2019, 08:14 PM   #2
Mini-Skoolie
 
Join Date: Feb 2019
Location: Central Washington
Posts: 18
Year: 1988
Coachwork: Thomas
This was a good question did you ever get it answered?
__________________
Our build: Odman Odyssey (previously dream catcher)
https://www.skoolie.net/forums/f11/faith-and-taylors-dream-chaser-26401.html
whiterose764 is offline   Reply With Quote
Old 04-08-2019, 02:50 PM   #3
Skoolie
 
Join Date: Jul 2016
Location: Western Oregon
Posts: 180
Year: 1995
Coachwork: Blue-Bird
Chassis: TC RE 3408
Engine: 5.9 Cummins 12V Mechanical
Rated Cap: Blue-Bird says 72 pass.
I think it's a good question too. But obviously it's not a popular question. I've found numerous posts on this forum about floating floors, but I'm not comfortable with that concept.

I want my floor as well-secured as possible. Just sitting there, held in place only by gravity does not fit into my definition of well-secured.
gs1949 is online now   Reply With Quote
Old 04-08-2019, 03:18 PM   #4
Bus Crazy
 
Sleddgracer's Avatar
 
Join Date: Nov 2018
Location: south east BC, close to the Canadian/US border
Posts: 1,723
Chassis: still looking for my bus
Quote:
Originally Posted by gs1949 View Post
I think it's a good question too. But obviously it's not a popular question. I've found numerous posts on this forum about floating floors, but I'm not comfortable with that concept.

I want my floor as well-secured as possible. Just sitting there, held in place only by gravity does not fit into my definition of well-secured.
I'm planning on gluing my foam board to the floor, and gluing tongue and groove plywood flooring to the foam board- the floor won't be moving anywhere and it will do a better job of insulating the floor without the framing
Sleddgracer is offline   Reply With Quote
Old 04-08-2019, 03:31 PM   #5
Bus Nut
 
Join Date: Apr 2010
Location: Lebanon, IN
Posts: 250
Year: 1998
Chassis: TC 2000 bluebird
Engine: 5.9 cummins
Rated Cap: 66
There are screws designed for this. They are made to deive through wood, then self tap into steel. Get the countersunk head version and it goes real fast. They can even drive right into the ribs below the floor. Just make sure you look at what is underneath first.
miltruckman is offline   Reply With Quote
Old 04-08-2019, 04:06 PM   #6
Bus Geek
 
Join Date: May 2016
Location: Eastern WA
Posts: 4,590
Year: 2002
Coachwork: Bluebird
Chassis: All American RE (A3RE)
Engine: Cummins ISC (8.3)
Rated Cap: 72
Quote:
Originally Posted by miltruckman View Post
There are screws designed for this. They are made to deive through wood, then self tap into steel. Get the countersunk head version and it goes real fast. They can even drive right into the ribs below the floor. Just make sure you look at what is underneath first.
Do you have any additional details on these? Maybe a web link?
PNW_Steve is online now   Reply With Quote
Old 04-08-2019, 05:11 PM   #7
Skoolie
 
Join Date: Jul 2016
Location: Western Oregon
Posts: 180
Year: 1995
Coachwork: Blue-Bird
Chassis: TC RE 3408
Engine: 5.9 Cummins 12V Mechanical
Rated Cap: Blue-Bird says 72 pass.
Without furring strips every couple of feet or so I would be worried the foam would collapse. Perhaps not too quickly, but eventually I think you would end up with a low spot in the middle. I think 2X2s every 18-24 inches screwed through the steel floor into the support structure, would prevent the floor from sagging. Then the plywood could be screwed to the 2X2s with plenty of screws that are too short to penetrate through the 2X2. So there would be no direct thermal bridging, just some places where wood was the only insulation, which I could live with..

I realize that there is foam that is denser and more resistant to compression than the standard foam, but I would still want the plywood to be supported by 2X2s at least every 2 feet. Overkill perhaps, but I have several extremely large friends and I am not small myself. I would really hate to have a floor that sagged in the middle.
gs1949 is online now   Reply With Quote
Old 04-08-2019, 05:29 PM   #8
Bus Crazy
 
Sleddgracer's Avatar
 
Join Date: Nov 2018
Location: south east BC, close to the Canadian/US border
Posts: 1,723
Chassis: still looking for my bus
Quote:
Originally Posted by gs1949 View Post
Without furring strips every couple of feet or so I would be worried the foam would collapse. Perhaps not too quickly, but eventually I think you would end up with a low spot in the middle. I think 2X2s every 18-24 inches screwed through the steel floor into the support structure, would prevent the floor from sagging. Then the plywood could be screwed to the 2X2s with plenty of screws that are too short to penetrate through the 2X2. So there would be no direct thermal bridging, just some places where wood was the only insulation, which I could live with..

I realize that there is foam that is denser and more resistant to compression than the standard foam, but I would still want the plywood to be supported by 2X2s at least every 2 feet. Overkill perhaps, but I have several extremely large friends and I am not small myself. I would really hate to have a floor that sagged in the middle.
there was someone that posted on this subject before - they had the numbers calculated of how much pressure would be exerted on the foam through 5/8ths plywood - I don't remember the exact figures, but they were huge - the plywood spreads the pressure out very well - using rough figures, a 300# person standing on one foot would exert about 7.5 lbs per square inch - standing on 2 square feet of 5/8 plywood would reduce that down to about 1.5 pounds per square inch or less
Sleddgracer is offline   Reply With Quote
Old 04-08-2019, 05:45 PM   #9
Bus Geek
 
o1marc's Avatar
 
Join Date: Dec 2017
Location: Dawsonville, Ga.
Posts: 6,871
Year: 1999
Coachwork: Genesis
Chassis: International
Engine: DT466/3060
Rated Cap: 77
Quote:
Originally Posted by gs1949 View Post
Without furring strips every couple of feet or so I would be worried the foam would collapse. Perhaps not too quickly, but eventually I think you would end up with a low spot in the middle. I think 2X2s every 18-24 inches screwed through the steel floor into the support structure, would prevent the floor from sagging. Then the plywood could be screwed to the 2X2s with plenty of screws that are too short to penetrate through the 2X2. So there would be no direct thermal bridging, just some places where wood was the only insulation, which I could live with..

I realize that there is foam that is denser and more resistant to compression than the standard foam, but I would still want the plywood to be supported by 2X2s at least every 2 feet. Overkill perhaps, but I have several extremely large friends and I am not small myself. I would really hate to have a floor that sagged in the middle.
I'm using standard Owens Corning Formular 250 rigid pink foam in 1" thickness. It has a compression strength of 25psi. That's 3600psf. Plywood has a compression strength of between 4k and 6k/psi. So after plywood is laid you have a compression strength of 4025-6025psi (approx. 750000psf). What is it you will have on that floor that would make you think you will compress the foam enough to sag over a 2' square?
o1marc is offline   Reply With Quote
Old 04-08-2019, 08:26 PM   #10
Skoolie
 
Join Date: Jun 2015
Location: Asheville, NC
Posts: 168
Year: 1999
Coachwork: American Cargo 14'L x 7'8"W x 7'H Box
Chassis: Ford E350 Cutaway
Engine: 7.3L Powerstroke
Rated Cap: 11500 lbs
Quote:
Originally Posted by PNW_Steve View Post
Do you have any additional details on these? Maybe a web link?
I got these self drilling and tapping screws at the local Fastenal store to attach new deck boards to my 10k lbs flatbed trailer. Going to use the same type screws for the floor of my box van conversion.
alpine44 is offline   Reply With Quote
Reply

Tags
fastening, sub floor

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 05:45 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2019, vBulletin Solutions, Inc.