Rolled asphalt roof on a park model RV

[redramer]

Greetings, been years since I've posted here and the wife and I still marvel at our year long travel pics around N America.
Now we're anchored in a great RV park, in a 94 Prowler park model in VG condition, it's waterfront and she had to have the view.
She got the view, I got the maintenance and next job is upgrading the rolled asphalt roof. YES, you heard it right. The previous owner rolled it right over the existing rubber roof.
No signs of leaks but... local contractors are looking for $20k ++ to tear everything off for new rubber.
I'm thinking... why not rubber right over what's there... aka a mineral surface (same as asphalt on a pitched roof - itibiti stones). It's composition would guarantee any glue to stick to it.
Looking for folks who've come across such a job, or tell me I'm crazy or sane and why.
attached - closeup of vent cleaning out and roof material and LS view of unit.
Thanks

 

[gwinger]

I would think any adhesive would have a hard time sticking to the asphalt base, even with the granuals on it. The heat of the sun would soften the asphalt base and oils will flash and seep to the top.

 

[TheBar]

Asphalt is common on older mobile homes and works well. I would never recommend it for an RV. But since its already done I'd just recoat it again with a quality coating like white or silver Kool Seal when needed.

But I'd remove it completely if you choose to have a traditional roof like TPO. Which means you'd have a horrible mess on your hands. Literally a mess on your hands, clothes. and the RV itself.

 

[gwinger]

Asphalt is common on older mobile homes and works well. I would never recommend it for an RV. But since its already done I'd just recoat it again with a quality coating like white or silver Kool Seal when needed.

But I'd remove it completely if you choose to have a traditional roof like TPO. Which means you'd have a horrible mess on your hands. Literally a mess on your hands, clothes. and the RV itself.

We lived in a mobile home when we first got married. I did coat mine about every 3 years with the appropriate sealer. Not a fun job, but the roof held up til we sold it 10 years later.

 

[Mark_K5LXP]

I'm thinking you're already approaching the load limit of the structure with what's there much less adding more. This isn't a house with 2x8 or whatever rafters and OSB decking. Game plan is important here, what one does when the exit is near term vs long term. $20K would put a nice roof on my S&B so I'd be looking for other bids.

Mark B.
Albuquerque, NM

 

[Jackiemac]

Would you be allowed to build a structure above it? Might be a lot cheaper.

 

[Gary RV_Wizard]

Agree with The Bar - stick with what you got (pun intended!). If it's still in good condition, I'd coat it with a reflective (white or silver) sealer for cosmetic & heat-shedding purposes. Henry's 887 Tropi-cool or similar. If getting shabby, maybe coat with an asphalt emulsion, with or without fiber, to re-build the asphalt layer itself. Henry's has a line of products for that sort of surface and all are top quality stuff.

I don't think the extra layer will add significantly to the structural load - probably another 60-100 lbs depending on what you choose. The existing rolled roofing added a few hundred, but if it's not falling in now I wouldn't worry. The widest roof span is only 8 ft.

 

[Utclmjmpr]

Henry's 887 would be ideal and available at Home Depot.. prep is key,, It won't break the bank and you can use a roller, a little goes a long way..>>>Dan

 

[gwinger]

I'm thinking you're already approaching the load limit of the structure with what's there much less adding more. This isn't a house with 2x8 or whatever rafters and OSB decking. Game plan is important here, what one does when the exit is near term vs long term. $20K would put a nice roof on my S&B so I'd be looking for other bids.

Mark B.
Albuquerque, NM

Not so much replacing the roof, the prep work would be time consuming, especially if they glued down the rolled roofing.

 

[Kirk]

From what I am reading, none of us have ever delt with the roofing that you have on an RV. As a result, the advice is little more than guessing, which is all that I would be able to add. The one thing that I do notice is that the picture makes that appear to be a destination trailer, rather than the typical RV. I don't know a lot about them as I have never owned or worked on one, but I do know that they are usually heavier than similar sized travel trailers so they may be constructed differently.

 

[TheBar]

I'm thinking you're already approaching the load limit of the structure with what's there much less adding more. This isn't a house with 2x8 or whatever rafters and OSB decking. Game plan is important here, what one does when the exit is near term vs long term. $20K would put a nice roof on my S&B so I'd be looking for other bids.

Mark B.
Albuquerque, NM

Kool Seal is applied with a roller brush much like an acrylic coating. Very little weight there.

 

[redramer]

Thanks guys, you're all hitting on what I went through.
The attached pics are 1- a new roof last year cost $16k built over existing rubber, and because we got frost shifting soil in Winter, it's already playing with the aluminum...
Pic 2 - I also worry about the weight, seeing I might have 3 rolls of asphalt.
Pic 3 - 2 yrs ago I had to install drip edge trim because the rolled roof was starting to crack on the 90 degree edge. It's all sealed now.
So basically the roof is OK, BUT, there are expansion cracks starting to show and the White coating I put on isn't going to cut it.
I'm going to look into this Henry Silicone stuff. Looks like a decent product so far. Even good to -40 F/C! Winter's a killer up here.
Does anyone think it would last 10 years?
Denis

 

[redramer]

pictures

 

[TheBar]

In the same way newbies think an RV is just a house on wheels we are thinking the exact opposite. A 32 year old park model is a mobile home built more like a house with a flat tar roof than an RV. It very likely came from the factory with the asphalt roof. And therefore just has a thin layer of an asphalt coating rolled over it.

That is the appropriate roof for a park model. Forget about using RV coatings which will not stick to that kind of roof.

If its cracked or thin roll more asphalt coating over it.

 

[TheBar]

I'm going to look into this Henry Silicone stuff. Looks like a decent product so far. Even good to -40 F/C! Winter's a killer up here.
Does anyone think it would last 10 years?
Denis

You are overthinking this. I think Henry Silicone will be a much bigger mess than what you have now. It likely won't stick to the oil based existing roof.

 

[gwinger]

pictures

Are these pictures of your existing roof? It doesn't look like the same roof as your first picture.

 

[RayIN]

Asphalt is common on older mobile homes and works well. I would never recommend it for an RV. But since its already done I'd just recoat it again with a quality coating like white or silver Kool Seal when needed.

But I'd remove it completely if you choose to have a traditional roof like TPO. Which means you'd have a horrible mess on your hands. Literally a mess on your hands, clothes. and the RV itself.

I agree. That's an ideal situation for a sprayed-on roof coating, and no worries about a petroleum ingredient in the applied coating.
I would use a strong water spray first to remove loose dirt on the roofing.

 

[Gary RV_Wizard]

Kool Seal is applied with a roller brush much like an acrylic coating. Very little weight there.

A 5 gallon pail of Henry's 887 (Tropi-cool) weighs 55 lbs and covers 300-320 sq ft. It's not gonna overload anything that's not already too far gone to save.

 

[DutchmenSport]

I'm wondering why you feel the need to do anything to the roof at all. You said its not leaking. Apparently there are no problems. Asphalt roofs last for years and years. On a conventional house, you can expect 20 to 50 years, depending on the actual brand. I would think, even on a mobile home, park model, or any camper, as long as the edges are not lifting and no cracks are forming, they why do anything? That asphalt roofing will probably outlast the life of the entire camper. When it's towed away for the junk yard someday, that roof will still be in great shape. Your trailer frame will rust out before that roof gives out.

 

[redramer]

Good comments
No, that framed up roof is down the road
Existing white coating coverage is latex based and it's not bleeding
Do I really need it??? If I want to keep it for the next 5-10 years, now's the time to giterdone.

So, I read the Henry _Test-adhesion_Recs and the Application_Guide where it's rec that seams, flashings, etc be coated with 1/8" of coating. That's would be my concern and with the heavy rec coating at those locations, then I feel the Silicone can move and still remain sealed. On the nice flat surfaces, there's really not much movement and a good 11mil coating, maybe 2 coats, I feel confident will last. Henry's testing method will tell if I'm good to go.
In so far as getting myself into a real mess, I think I'm there already... A little bit of Henry shouldn't matter too much more.

thanks again guys
Denis