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there is a way you can do it yourself, easily and reasonably.
I have been in the roofing industry almost 40 yrs, seen and used every single product there is for water proofing.
liquid PMMA is the way to go on rv’s, incredibly tough yet flexible, and extremely durable. comes with a 25-35 yr warranty on the PRODUCT, but has a much longer service life. you could beat on it all day with your hammer…you might scuff it.
you want Soprema Alsands RS 230 Flash
i brought a 25lb 5 gal pail home from work, used a 1/4 can for 2 coats, added maybe 7 or 8 lbs to my camper. done forever, spray the pine needles and stuff off every now and then, nothing else to do, one less thing to ever worry abouthere’s some info
https://www.soprema.ca/product/alsan-rs-230-flash-587/https://www.google.com/search?q=pmma+roof+coatings&rlz=1C1ILPI_enCA776CA776&oq=pmma+roof+coatings&aqs=chrome..69i57.6877j0j7&sourceid=chrome&ie=UTF-8
and here’s what it looks like, and on my camper
oh ya, you definitely want to be wearing HD gloves with this stuff
The most important factor for me to know here is how old was the roof and was there a problem with it. I have worked on RV roofs for decades as part of my work and the overwhelming problem is not the rubber itself. In my experience, that is almost never is a problem unless a tree ran into it or something similar.
When you coat the rubber, you are often putting time and money into the least problematic thing on your roof. The problem is almost always the aluminum molding around the front and sides not being sealed or the roof vents, etc, not being seal. Maintaining the caulk seal there is incredibly important and in my opinion leads to more sidewall delam than any other factor.
Steve and Andra
2012 F350 6.2 gasser SRW LB
Fab Fours front and rear in case we run into a rhino
2019 Northstar Laredo SCGreat reply Dieseldawg. Providing the description and a web site along with a picture of the finished product is very helpful. Ardvarks views are also helpful. Most of know the flashing and all the vent holes along with seams are normally the problem, but it never hurts to tell the people that are new to RV’s. The propensity of RV’s to start leaking after only a couple years is why I am not a fan of extra stuff that require holes to be anywhere on the RV. Ladders, roof racks, solar, sky lights and awnings are all non essential items that IMO do more harm than good.
for prep hobiekaw, clean and wash the roof- that’s it. i should mention you should peel your old rubber off. alsans needs a fairly solid surface to adhere to and work- alum, wood, concrete, metal, etc. my camper is an old one, ’89 and had an alum roof, it just needed old caulking scraped off and to be cleaned.
i’m not an rv tech, but if you want to talk roofs, i’m your man, 4th gen in this trade.
and ardvark is right, leaks rarely happen to the rubber or tpo unless there’s some physical damage done to it, like any roof, your house, the mall, your rv, 99% of all leaks occur in the details.
vents, a/c units, roof racks, stacks, any protusion threw the roof is where it almost always starts, and even with the tpo and epdm roofs on the newer units today, they STILL use caulking to seal these protusions to your rubber roof, or at the edges- which means constant matainence.
this is where alsans comes into play. this is not the “snow roof” junk you get at the rv shop, you will need to go to a dedicated roofing supplier for this, it is a 2 stage compound you mix that is light yrs ahead of caulking and eliminates it completely. and i mean any caulking or butyl, ya, we have hundreds of brands at work we use all the time and they are totally outclassed by PMMA. a similar compound to our PMMA is actually used for making fighter jet canopies.
if caulking was a 1950 chev with a stovebolt 6, alsans is a 2019 3500 D-Max
it applies to all the details on your roof, and you bring it right down onto all your side/fr/rr mouldings thereby completely wiping out any more caulk maintainece-forever….only downside i see is less work for rv shops on camper roofs…lolwe did a “floating” roof over a poop tank at the local sewage plant, first we put down a torch-on roof, then coated it with alsans because they have to pressure wash the “klinkers” off the roof every few days. in a month or so under that many pressure washings, the torch on membrane by itself would disintegrate.
the engineers on this job say at least a 30 yr life span under constant washings with the alsans. you can walk on it, even drive your car on it, we have water-proofed under ground parkades with it.
sounds way too good? the only catch, a 5 gal pail is about 250 clams and as far as i’m aware, RS 230 does’nt come in anything smaller…is your rubber roof FULLY bonded to the roof, or do you have a few loose spots as the glue breaks down? (common prob, seen many rv roofs “fluttering” as they pass me on the hiway at 75mph…)
only problem i could see is if your rubber is not stuck down 100%, may be too flexy, too much movement. alsans itself will bond to practically anything, but it has to have a reasonable solid base for it to work. and you would not need to remove any details on your roof, you cut the rubber around the flanges instead and leave everything where it is.
i would suggest try it around a vent or something to test it, but as it don’t come in small amounts it’s kinda impractical.
if you have probs with your rubber roof, try this caulk, we have found it to be one of the better, if not best epdm caulks out there, Carlisle lap sealant, still will have to maintain every couple yrs or so…My previous truck camper had a metal roof and I put two coats of Henri-Tropic Cool over it. It’s a 100% silicone material that has a lifetime warranty and is 100% waterproof. Did the roof with a roller and 1 gallon which was about $75. Knocked the external roof temperature down by 32 degrees on a hot sunny day and the interior ceiling temps by 16 degrees.
Neil & Yoly
2016 Ram 2500HD Tradesman, 2WD Crew Cab, 6.4L Hemi
2018 Travel Lite 840 SBRX
Honda EU2000iMy previous truck camper had a metal roof and I put two coats of Henri-Tropic Cool over it. It’s a 100% silicone material that has a lifetime warranty and is 100% waterproof. Did the roof with a roller and 1 gallon which was about $75. Knocked the external roof temperature down by 32 degrees on a hot sunny day and the interior ceiling temps by 16 degrees.
All this talk about RV roofs brings me to the one question I have NEVER gotten answered, in fact I have got an aswer at all.
What is the rubber (etc etc) roof stuff? I have owned a LOT of houses, none of them have a rubber roof, I have had: Tile, Concrete, Rock over tar, Asphalt shingles, metal both corrugated and standing seam, Sandbags (3 layers thick), Palm leaves.
ONE roof stands out: Metal! My next door neighbor had a metal roof, put on when the house was built in 1852.
The question is: WHY not a metal or fiberglass roof over the other stuff with its extremely limited life, problematic challenges, high and expensive upkeep. Or is the real answer…follow the money?
Don
US Army Retired
2019 F 350 CC-LB King Ranch
Hill Country of TexasThe RV industry used metal roofs for years, although not nearly the thickness you will find in your home. Some of the roofs were seamed and then caulked which were find until the caulking broke down and of course high-end motor homes still used fiberglass. Some of them used one large piece of metal and I believe that metal is still obtainable, although I have never tried to redo a metal roof.
I think the switch to rubber was motivated by cost in part, but a properly installed rubber roof on an RV which is maintained will last for a very long time. The normal warranty is at least ten years and I have seen many that are 20 years old and still going strong. Eventually the white wears off to the black on some materials and does well with a recoating.
All rubber roofs do not use the same material and the thicker material is hard to seal tightly at the edges before the trim strip is screwed into place. It doesn’t look as nice as is the case with my new NorthStar, but it is fully serviceable and not likely to cause trouble. The rubber roofs I see flapping in the wind that I have seen are normally on entry level units and there is cornercutting on other areas as well.
The rubber roof on my Hallmark is now 15 years old and still is in perfect shape as is the one on our 12 year old fifth wheel.
Rubber may not be perfect, but it has a lot going for it! 🙂
Steve and Andra
2012 F350 6.2 gasser SRW LB
Fab Fours front and rear in case we run into a rhino
2019 Northstar Laredo SCAll this talk about RV roofs brings me to the one question I have NEVER gotten answered, in fact I have got an aswer at all.
What is the rubber (etc etc) roof stuff? I have owned a LOT of houses, none of them have a rubber roof, I have had: Tile, Concrete, Rock over tar, Asphalt shingles, metal both corrugated and standing seam, Sandbags (3 layers thick), Palm leaves.
ONE roof stands out: Metal! My next door neighbor had a metal roof, put on when the house was built in 1852.
The question is: WHY not a metal or fiberglass roof over the other stuff with its extremely limited life, problematic challenges, high and expensive upkeep. Or is the real answer…follow the money?[/quote]rubber roofs are actually called EPDM (Ethylene Propylene Diene Monomer) and about the only thing they have going for them is they are cheap, and very quick to lay.
EPDM is used mainly for commercial buildings (and rv’s), like you say, good luck finding an EPDM roof on a house (except for hidden gutters). And it’s used even more so in new comm.construction simply for the speed aspect. On new construction almost all work is on hold until the roof is on and shedding water, and this is the one big advantage of EPDM, the rolls come in all diff sizes, comman size is 10 sq rolls (1000 sq feet) and a very large amount of squares can go down in a day with not a lot of manpower.
It is much faster than a torched on 2ply SBS membrane, TPO roofs, or Tar&Gravel roofs- shingles, slate, tiles are not relavent as they are for steep roofing (anything more than a 3:12 pitch) and don’t really apply to flat or almost flat rv roofs.
i have seen a few new units come with TPO roofs(Thermoplastic Polyolefin). these membranes are lighter than EPDM, and more durable. Detail work and roof seams are much better with this than EPDM cause unlike EPDM where everything is glued or caulked, it is all welded on TPO with special heat guns. Material is more expensive than EPDM right now (as it grows in use, price comes down) and the equipment to apply TPO roofs is extremely expensive. A robotic “Caddilac” welder is in the neighborhood of $15-20 grand and even the special hand welders are around $5-900 a pop.
as the price on it comes down (has only been on the market since the late 80’s-early 90’s) i belive it will soon end up on almost every rv and why not, it’s lighter and much better.
Epdm will eventually break down, it’s petro based so it can’t be stopped. Keeping a epdm roof covered (with emulsion, or as on buildings, covered in ballast rock) and supple will help prolong it’s life, but i have’nt seen too many epdm roofs past 20-25 yrs in almost 4 decades in the roofing industry. it is also very suspectible to puncture damage. i have come across cigarette burns right threw epdm roofs, even seen holes punched threw them from birds dropping nuts, rocks, sticks on them.
want longivity? hands down slate, concrete tiles. metal? ya 50 to 100 or so yrs (rust) or 200-3 even 400 yr old slate roofs still out there.Perhaps the crux of any discussion about durability and reliability has as much to do with how much folks are willing to pay as it does about the material being used. I think it is certainly possible to build an RV that will last lifetimes and the roofs on high end motorhomes and buses to a long ways in meeting that need as do the roofs on high-end fifth wheels.
The same is true to wall construction, etc. For the manufacturers it is a juggling act and they have to be able to sell what they build framed against the RV industry statistic that fully 50% of first time builders keep their rig less then two years and use it less than 20 days out of the year.
In the end you still get what you pay for.
Steve and Andra
2012 F350 6.2 gasser SRW LB
Fab Fours front and rear in case we run into a rhino
2019 Northstar Laredo SCThe above should read “fully 50% of first time buyers keep their rig less then two years and use it less than 20 days out of the year.” Sorry for the type. That is the actual industry statistic. Buyers tend to trade often and keep their purchases for relatively short periods of time.
Steve and Andra
2012 F350 6.2 gasser SRW LB
Fab Fours front and rear in case we run into a rhino
2019 Northstar Laredo SCWhen you start juggling cost versus usage for the average owner RVs come out being terrible investments (which I get to say having owned multiple RVs now over the last almost 4 decades). They depreciate like they are going over a waterfall and most folks sell or trade their RV long before it is close to warn out.
What I so often see, speaking as a tech, is folks trying to make their entry level camper into the high-dollar rig they really wanted and keeping it briefly before trading up to the rig they wanted from the git-go. At every price point there are multiple factors that come into play determining at which price point an RV will compete, roofs being one factor, sidewall construction being another, etc.
Steve and Andra
2012 F350 6.2 gasser SRW LB
Fab Fours front and rear in case we run into a rhino
2019 Northstar Laredo SCThe above should read “fully 50% of first time buyers keep their rig less then two years and use it less than 20 days out of the year.” Sorry for the type. That is the actual industry statistic. Buyers tend to trade often and keep their purchases for relatively short periods of time.
and this is exactly why a lot of manufactors give a “lifetime” warranty. they KNOW it will be sold/traded shortly.
ever notice how lifetime warranty’s are not transferable from the orig owner?
i know in our trade, just the last few yrs a lot of our suppliers have been switching to “lifetime” warranty
it gives them something to trumpet to possible customers, but how do you “lifetime” warranty a 25 or 30 yr shingle??
and what a lot of people don’t know about most “lifetime” warranties, there pro-rated, as time marches on your warranty is worth less and less
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