2006 Rockwood Premier 2317G - Full Rebuild

Dunner

Member
Mar 27, 2022
19
Canada
Happy Wednesday Everyone!

So im planning out how I will rebuild a new roof structure. I figured it's be wise to look at how the old roof was built, in order to gain some wisdom. The interior of the old roof was skinned with a thin aluminum sheet/foil - so I removed that to have a better looks at what kind of cross members were used. Here's what i found: Sweet Nothing....

IMG_0214.jpg

...Well nothing but for a couple lateral members which I would assume support the optional AC unit.....

So from what I can see, the folks down at Forest River are counting on the adhesive bond between the foam sandwiched between the aluminum inner skin and the fiberglass outer skin. I was quite surprised! (shocked, even!)

Needless to say I want to rebuild this a bit stronger. Of coarse, I want to be mindful of weight. The original roof was just over 1" thick (1" foam board and wood framing, with the skins glued on either side. Maybe 1-1/8" total thickness). To save on ripping wood down, I want to rebuild the roof to be 1.5" thick. I just hope the extra inch of thickness doesn't interfere with the mattresses when I go to lower the roof back onto the camper walls.

I'm hoping the wiser and more learned members of this forum might have some advise for me at this stage.

Should I be framing cross members every 16"? 24"?.

Am I asking for trouble by making this new roof thicker and heavier?

Does anyone know of a readily available "foam safe" contact cement?

I'd be glad for some tips at this stage!
 
Sep 28, 2018
17
In watching this rebuild, (very impressive by the way) I can't help but be amazed that these things sell for $15-20K new. What are the profit margins really like?
 

stierheim

Member
Apr 22, 2013
63
Should I be framing cross members every 16"? 24"?.

Am I asking for trouble by making this new roof thicker and heavier?

Does anyone know of a readily available "foam safe" contact cement?

I'd be glad for some tips at this stage!
You probably don't need any more framing than is already there (which is to support the AC unit). Once the foam is glued to the roof, it becomes very stiff. A person can stand on those roofs to work on the AC unit. Also, you will probably use much stiffer foam than the cheap stuff the factory used.

As far as roof thickness goes: On my PUP, an additional 1/2" would cause a problem in getting the roof latched closed. Normally (with bedding on the beds) with dry canvas, the roof easily goes fully down and an additional 1/2" thickness would not be a problem. However, when the canvas is wet it swells and the roof is tight when latching it and I suspect that an additional 1/2" thickness across the entire roof would make it difficult or impossible to latch.

You can get water based contact cement at any HW store. It will work with foam.
 
Sep 28, 2018
17
Hey Dunner, What happened to you? I need a rebuild fix real soon. I think a lot of us are living vicariously through your rebuild wishing we had the time and skills to do what you have been doing. Please provide an update with photos real soon!!!!
 

Dunner

Member
Mar 27, 2022
19
Canada
Dear Friends of the forum! I ask for your forgiveness in not keeping you apprised of my progress lately. Selfishly, I've been in a bit of a "get'er done" kind of mind set given my shrinking timeline.

Nonetheless much has happened, some of which I will share with you now:

I got the Filon outer skins back on. Pretty much the reverse of removal. The original lower J trim was wrecked when I took things apart, so I found a white aluminum J-trim in the siding section at home depot which worked great. I stapled that along the bottom, dropped the panels in, and proceeded to reinstall the exterior trim, moldings, cable hatches, etc. Bought a bunch of Butyl tape off amazon and its comforting to know everything has a fresh seal on it. I didn't add any extra fasteners to the outer skins. Between the lower J trim, upper trim, and all the through-wall hatches, lights, latches etc, each panel is very secure. The curved panels on the front and back end required an extra pair of hands. Those suckers really don't want to bend without a fair bit of convincing. This was one of the more frustrating parts of the project so far, but alas, they are on!

Now for the Roof Build!

Luckily I had my old side boards kicking around which was helpful in determining the proper height to mount the new side boards to the lift system. With the help of Mrs. Dunner, I got those mounted on first, followed by the front and rear boards (3/4 Ply just like the side boards) which created the perimeter of the roof structure. I opted to keep overall thickness of the roof close to the original (increasing by about 3/8" overall. I ripped 1" x 1.5" cross members from nice straight 2x4's and spaced them every 24" which gave me something of a ladder frame (with a 14" x 14" opening for a roof vent in the rear passenger side corner). Once I got to this stage, I realized the rear of the roof was lifting higher than the front of the trailer, so I adjusted my lift system to get this level again.
IMG_0226.jpg

I decided to use 1/4" Lauan plywood for the ceiling (which in my case actually measures thinner than 1/4" at about .195"). Again, my wonderful wife was a good sport in helping me get this glued and stapled to the ceiling. We were able to get the seems nice and tight, and I finished it off with white exterior latex paint. I had considered using FRP panels for this, but here in Canada those run about $85sheet vs $27 for Lauan - for my purposes, I'm ok with the compromise from a more "factory finish"

Side note - you can see in the picture below that I have a piece of steel flat-bar screwed into the side of the cross member for added strength. This made the 1" thick cross members very rigid while maintaining a short profile.

IMG_0229.jpg

With the ceiling installed, I now had 24" x 84" "pockets" that I could glue foam board panels into - thanks to Stierheim for the helpful comments - im following a hybrid approach between original factory design and my desire to add some extra structure.

I used 1" XPS foam board. This was easy to cut to size on my table saw, and I used "Weldbond" as my adhesive since it says that its foam compatible right on the label.

IMG_0235.jpg IMG_0236.jpg IMG_0233.jpg

With the foam glued into the cavities, I added some vertical supports inside of the trailer to maintain a very slight arch in the roof. My thought here was just to avoid having the roof dip in the middle under its own weight. My theory was that by adding the supports, the glue would dry the Lauan-and-Foam sandwich in a slightly arched position, and hopefully hold its form once the glue was dry and the supports were removed. Next I coated the top-side of the foam with adhesive and fastened another layer of 1/4" (.195") Lauan Ply.

IMG_0234.jpg IMG_0238.jpg

With the majority of the roof now complete - I focused on the the front and rear radius edges of the roof. I cut thin strips of foam board as a backer rod, and laid in a pile of expanding foam (great stuff - big gap filler). Once dry, I cut it down close with a utility knife and used a palm sander to shape it as close as I could to a consistent radius. The results weren't awful but certainly plenty of pitting and voids here and there. Since im using a thin roof membrane, I suspect you'll see the imperfections, but I've made my peace with that - i am on a timeline after-all!

IMG_0239.jpg IMG_0240.jpg IMG_0250.jpg

Feels really great to have the roof most of the way built. This was by far the biggest part of the project in my mind. Glad for all the help here on the forum and elsewhere by those who have gone before me!

Next step - installing the EDPM roof membrane to make this thing waterproof!
 

Rusty park

New Member
Aug 29, 2017
1
Dear Friends of the forum! I ask for your forgiveness in not keeping you apprised of my progress lately. Selfishly, I've been in a bit of a "get'er done" kind of mind set given my shrinking timeline.

Nonetheless much has happened, some of which I will share with you now:

I got the Filon outer skins back on. Pretty much the reverse of removal. The original lower J trim was wrecked when I took things apart, so I found a white aluminum J-trim in the siding section at home depot which worked great. I stapled that along the bottom, dropped the panels in, and proceeded to reinstall the exterior trim, moldings, cable hatches, etc. Bought a bunch of Butyl tape off amazon and its comforting to know everything has a fresh seal on it. I didn't add any extra fasteners to the outer skins. Between the lower J trim, upper trim, and all the through-wall hatches, lights, latches etc, each panel is very secure. The curved panels on the front and back end required an extra pair of hands. Those suckers really don't want to bend without a fair bit of convincing. This was one of the more frustrating parts of the project so far, but alas, they are on!

Now for the Roof Build!

Luckily I had my old side boards kicking around which was helpful in determining the proper height to mount the new side boards to the lift system. With the help of Mrs. Dunner, I got those mounted on first, followed by the front and rear boards (3/4 Ply just like the side boards) which created the perimeter of the roof structure. I opted to keep overall thickness of the roof close to the original (increasing by about 3/8" overall. I ripped 1" x 1.5" cross members from nice straight 2x4's and spaced them every 24" which gave me something of a ladder frame (with a 14" x 14" opening for a roof vent in the rear passenger side corner). Once I got to this stage, I realized the rear of the roof was lifting higher than the front of the trailer, so I adjusted my lift system to get this level again.
View attachment 83537

I decided to use 1/4" Lauan plywood for the ceiling (which in my case actually measures thinner than 1/4" at about .195"). Again, my wonderful wife was a good sport in helping me get this glued and stapled to the ceiling. We were able to get the seems nice and tight, and I finished it off with white exterior latex paint. I had considered using FRP panels for this, but here in Canada those run about $85sheet vs $27 for Lauan - for my purposes, I'm ok with the compromise from a more "factory finish"

Side note - you can see in the picture below that I have a piece of steel flat-bar screwed into the side of the cross member for added strength. This made the 1" thick cross members very rigid while maintaining a short profile.

View attachment 83538

With the ceiling installed, I now had 24" x 84" "pockets" that I could glue foam board panels into - thanks to Stierheim for the helpful comments - im following a hybrid approach between original factory design and my desire to add some extra structure.

I used 1" XPS foam board. This was easy to cut to size on my table saw, and I used "Weldbond" as my adhesive since it says that its foam compatible right on the label.

View attachment 83539 View attachment 83540 View attachment 83541

With the foam glued into the cavities, I added some vertical supports inside of the trailer to maintain a very slight arch in the roof. My thought here was just to avoid having the roof dip in the middle under its own weight. My theory was that by adding the supports, the glue would dry the Lauan-and-Foam sandwich in a slightly arched position, and hopefully hold its form once the glue was dry and the supports were removed. Next I coated the top-side of the foam with adhesive and fastened another layer of 1/4" (.195") Lauan Ply.

View attachment 83543 View attachment 83542

With the majority of the roof now complete - I focused on the the front and rear radius edges of the roof. I cut thin strips of foam board as a backer rod, and laid in a pile of expanding foam (great stuff - big gap filler). Once dry, I cut it down close with a utility knife and used a palm sander to shape it as close as I could to a consistent radius. The results weren't awful but certainly plenty of pitting and voids here and there. Since im using a thin roof membrane, I suspect you'll see the imperfections, but I've made my peace with that - i am on a timeline after-all!

View attachment 83546 View attachment 83544 View attachment 83545

Feels really great to have the roof most of the way built. This was by far the biggest part of the project in my mind. Glad for all the help here on the forum and elsewhere by those who have gone before me!

Next step - installing the EDPM roof membrane to make this thing waterproof!
Great job.
 

Dunner

Member
Mar 27, 2022
19
Canada
Hey Folks!

Here's a bit of an update!

Roof Membrane:

Through my local RV dealer, I sourced some Dicor EDPM roof membrane and adhesive. This stuff wasn't particularly cheap, but I figured it was my best option since the old fiberglass skin wasn't saveable. This material is fairly thin at about .030", but seem quite resistant to tearing. I laid it out on the trailer overnight to get rid of the creases, and glued it on the next day. It was fairly straight forward to do, and the adhesive goes on very easy with a paint roller. Simply pull back a section of membrane to expose the wood surface, lay down the glue in an even coat, place the membrane over top, and push out the air bubbles (they recommend a broom to push the bubbles out, but I used a fresh paint roller instead which worked fine). I used about 3/4" of a gallon of adhesive on my 12ft roof. The membrane came off a 9ft roll, which provided enough width for the sides.

IMG_0264.jpg IMG_0265.jpg

For anyone who attempts this - I'd suggest you cut the material for the side rails as an extra panel. I tried to adhere the EDPM membrane on one of the sides while leaving it attached to the main roof piece, and due to the curve in the roof, I ended up with some unsightly creases and ripples in the material. (my thought was that one seamless piece of material would be ideal) I attached the opposite side as a separate piece, and it went on really nice and smooth. Some inconsistencies are also noticeable on the spray foam curved front and back edges, but not enough to bother me too much.

IMG_0274.jpg IMG_0275.jpg

Once the membrane was down, I used some flex tape to seal the seams, before I began reassembly of the trim. I bought new roof corner caps off of e-bay, but reused everything else. For those who don't know, removing old Butyl seal off of aluminum trim is a massive paint in the butt! But we got through it with minimal cussing and only a few lacerations on the fingers.

IMG_0280.jpg IMG_0281.jpg IMG_0282.jpg

With the roof trim on, I popped her back up and continued with re-assembly. Lots of the work from here on out is just the opposite of tear-down, replacing old fasteners along the way and making sure all the seams get properly sealed.


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Well - we're leaving this coming Friday for camping. Lots to do yet lol. I'm sure i'll have some interesting updates for yall this week!
 

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wyyup

New Member
Jun 1, 2022
1
Well.... How did it go. I stupidly bought way too much of a project that is likely going to be a full scale rebuild like you have done and I'm trying to decide if it's worth doing or just stripping it to the frame and screwing on some wood and selling it as a utility trailer to try to get my money back. Only $600 in but very intimidated.
 




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