Good Sam Club Open Roads Forum: Adhesive for Aluminum roof to plywood?
Open Roads Forum Already a member? Login here.   If not, Register Today!  |  Help

Newest  |  Active  |  Popular  |  RVing FAQ Forum Rules  |  Forum Posting Help and Support  |  Contact  

Search:   Advanced Search

Search only in Travel Trailers

Open Roads Forum  >  Travel Trailers  >  Small TT's

 > Adhesive for Aluminum roof to plywood?

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 3  
Next
Aubrey0418

Bradenton

New Member

Joined: 12/27/2019

View Profile


Offline
Posted: 01/04/20 08:10am Link  |  Quote  |  Print  |  Notify Moderator

My husband and I are rebuilding a camper and are about to get to our roof install. We are doing a seamless aluminum roof which will be going over plywood. We want to avoid using any type of screws as much as possible to install this roof.
What type of adhesive would you recommend using for aluminum to plywood? Also it's a 16ft camper so we will have to find a way to apply adequate even pressure throughout while laying the roof down..any suggestions on that?

ItsyRV

Desert SW

Senior Member

Joined: 10/02/2018

View Profile



Good Sam RV Club Member


Posted: 01/04/20 08:52am Link  |  Quote  |  Print  |  Notify Moderator

On my roof, (aluminum to wood & metal framing) they used 3M's Scotch Weld urethane adhesive. It was applied using the bead and roll method. The roof section was also 8' X 16'.


1994 Itasca SunDancer 21RB - Chevy G-30 chassis.


theoldwizard1

SE MI

Senior Member

Joined: 09/07/2010

View Profile


Offline
Posted: 01/04/20 12:00pm Link  |  Quote  |  Print  |  Notify Moderator

Two big issues when trying to glue metal to wood.

• Preparation. The aluminum should be "scratched" a bit (ScotchBrite) and wiped down with acetone. Light sanding on the wood and a tack cloth.
• Expansion rates of the two materials. Aluminum expands a LOT when heated (sun exposure). Wood only expands a little when it is warmed. BAD COMBINATION ! No adhesive can survive that for long periods !!

Aubrey0418 wrote:

Also it's a 16ft camper so we will have to find a way to apply adequate even pressure throughout while laying the roof down..any suggestions on that?

Lots of cinder blocks or other heavy weights.

Aubrey0418

Bradenton

New Member

Joined: 12/27/2019

View Profile


Offline
Posted: 01/04/20 12:02pm Link  |  Quote  |  Print  |  Notify Moderator

theoldwizard1 wrote:

Two big issues when trying to glue metal to wood.

• Preparation. The aluminum should be "scratched" a bit (ScotchBrite) and wiped down with acetone. Light sanding on the wood and a tack cloth.
• Expansion rates of the two materials. Aluminum expands a LOT when heated (sun exposure). Wood only expands a little when it is warmed. BAD COMBINATION ! No adhesive can survive that for long periods !!

Aubrey0418 wrote:

Also it's a 16ft camper so we will have to find a way to apply adequate even pressure throughout while laying the roof down..any suggestions on that?

Lots of cinder blocks or other heavy weights.


So are you saying we'll have no choice but to screw it down?

theoldwizard1

SE MI

Senior Member

Joined: 09/07/2010

View Profile


Offline
Posted: 01/04/20 12:07pm Link  |  Quote  |  Print  |  Notify Moderator

theoldwizard1 wrote:

Two big issues when trying to glue metal to wood.

• Preparation. The aluminum should be "scratched" a bit (ScotchBrite) and wiped down with acetone. Light sanding on the wood and a tack cloth.
• Expansion rates of the two materials. Aluminum expands a LOT when heated (sun exposure). Wood only expands a little when it is warmed. BAD COMBINATION ! No adhesive can survive that for long periods !!

Aubrey0418 wrote:

Also it's a 16ft camper so we will have to find a way to apply adequate even pressure throughout while laying the roof down..any suggestions on that?

Lots of cinder blocks or other heavy weights.


Best solution Hex self tapping stainless sheet metal screw w/sealing washer These will hold in plywood.

Shop for similar WITHOUT the rubber washer and you can buy those cheap.

* This post was edited 01/04/20 12:14pm by theoldwizard1 *

theoldwizard1

SE MI

Senior Member

Joined: 09/07/2010

View Profile


Offline
Posted: 01/04/20 12:52pm Link  |  Quote  |  Print  |  Notify Moderator

Aubrey0418 wrote:

So are you saying we'll have no choice but to screw it down?

ItsyRV wrote:

On my roof, (aluminum to wood & metal framing) they used 3M's Scotch Weld urethane adhesive. It was applied using the bead and roll method.

ItsyRV used an urethane adhesive which DOES have more flexibility than most adhesives. I assume by "bead and roll", he meant that a bead of the adhesive was applied to the wood (like where the rafters would be) instead of the entire surface (like a contact cement), the aluminum is then laid down and rolled.

I am no expert, but I think I would add the screws over the line of the adhesive. "Belts and braces !"

badsix

north bend or.

Senior Member

Joined: 03/11/2017

View Profile


Offline
Posted: 01/04/20 01:22pm Link  |  Quote  |  Print  |  Notify Moderator

why not use the EPDM rubber roofing material used on most RVs. its probably not much more than aluminum in cost and probably easier to install. use Dicor self leveling sealer for any penetrations and you'll be good to go. I sure wouldn't want an aluminum roof with screws of any kind in it if I was looking for long life. Google RecPro, Dicor EPDM roofing
Jay D.

Gdetrailer

PA

Senior Member

Joined: 01/05/2007

View Profile



Posted: 01/04/20 02:38pm Link  |  Quote  |  Print  |  Notify Moderator

badsix wrote:

why not use the EPDM rubber roofing material used on most RVs. its probably not much more than aluminum in cost and probably easier to install. use Dicor self leveling sealer for any penetrations and you'll be good to go. I sure wouldn't want an aluminum roof with screws of any kind in it if I was looking for long life. Google RecPro, Dicor EPDM roofing
Jay D.


Because "EPDM" and any other flexible non metallic roof solution is a short lived 10yr-15yr fix.

Aluminum can often go 30yr-50yrs without being replaced which makes aluminum far cheaper but yet far superior overall. RV industry moved to using EPDM, vinyl roofing because it is cheaper than aluminum roofing, requires less skill and less labor to install which = MORE PROFITS. It was not because it was better than aluminum!

As far as the OPs question, aluminum roofing does not need glued down, it is secured via screws around the entire perimeter, the middle floats. In fact it needs to float to allow for expansion and contraction with temperature changes.

The only places that will need screws is vents to hold the vents in place.

The perimeter screws are hidden via the trim pieces at the top of the walls.

The aluminum roofing is folded down over the side walls, then the top side wall trim is installed, a bead of butyl caulking is what is used to water proof between the roofing, walls and trim.

NRALIFR

Truck Camping Out West

Senior Member

Joined: 11/27/2005

View Profile



Posted: 01/04/20 03:51pm Link  |  Quote  |  Print  |  Notify Moderator

The aluminum sheet on the roof of my TC isn’t glued to the wood at all. IIRC there is a layer of felt or closed cell foam between the aluminum and the wood, but it’s held down by the perimeter trim and screws. I don’t think I’d try to full-spread glue it.

I would also pass on the EPDM, TPO, or any other flexible membrane roofing. Nothing beats aluminum.

In other words, what he said ^ [emoticon]

[emoticon][emoticon]


2001 Lance 1121 on a 2016 F450


Lwiddis

Near Annett’s Mono Village, Bridgeport, CA

Senior Member

Joined: 08/12/2016

View Profile



Good Sam RV Club Member

Offline
Posted: 01/04/20 04:38pm Link  |  Quote  |  Print  |  Notify Moderator

No issue with adhesive, should be used, but screws are also necessary IMO.


Winnebago 2101DS TT & 2020 Chevy Silverado 1500 LTZ Z71, 300 watts solar-parallel & MPPT, Trojan T-125s. TALL pole for flags. Prefer USFS, COE, BLM, NPS, TVA, USF&WS, state & county camps. Bicyclist! 14 year Army vet - 11B40 then 11A - (MOS 1542 & 1560)


Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 3  
Next

Open Roads Forum  >  Travel Trailers  >  Small TT's

 > Adhesive for Aluminum roof to plywood?
Search:   Advanced Search

Search only in Travel Trailers


New posts No new posts
Closed, new posts Closed, no new posts
Moved, new posts Moved, no new posts

Adjust text size:




© 2020 CWI, Inc. © 2020 Good Sam Enterprises, LLC. All Rights Reserved.