TimeTraveler Report post Posted August 19, 2020 New Motorhomes have one piece roofs and don't have to have joints sealed with Dicor every two years or less... however our 05 does. It went 8 years because ti was stored inside. e had it redone this spring. Didn't cost much this time. factory was over 700.00. Surely there is a better long life sealant with UV inhibitors, that doesn't bleed all over the sides, in nasty white streaks, every time it rains???? What is it ? Share this post Link to post Share on other sites
hermanmullins Report post Posted August 19, 2020 TT, I had our coaches roof done in Perry at the National in 2014. It was done at the same time I had the coach washed. It was some sort of spray on and cost an additional $50.00 and lasted for about three years. I do keep the coach inside when not in use. Will have it done again in Perry if I can find the same crew. Herman Share this post Link to post Share on other sites
jleamont Report post Posted August 19, 2020 Truck bodies and semi trailers use Sika brand products and they last a lifetime. As long as the roof is not a rubber product I cannot imagine why you could think outside the box. Truck body roofs are either metal or fiberglass https://usa.sika.com/en/construction/adhesives-sealants.html Share this post Link to post Share on other sites
hermanmullins Report post Posted August 19, 2020 Joe is there a Sika product that isn't Black? I looked at the website and saw some good products but all that were for floors or roofs were Black. I can't imagine putting a black coating on an RV roof. Maybe I didn't see the correct material. Herman Share this post Link to post Share on other sites
manholt Report post Posted August 19, 2020 UV Rays will destroy white, not black! You can also paint over it...I don't care what my roof color is...I'm not up there to see it. Share this post Link to post Share on other sites
rsbilledwards Report post Posted August 19, 2020 Ok my take on this perpetual subject and outside the box and a little history leading to today.. Having spent 40 odd years in the automotive restoration business I like thinking outside the box on problems such as this. I joined the ranks of Rving 11 years ago with a 2001 Safari Zanzibar. While the roof was in pretty good shape, always exposed to the elements, it needed a good scrubbing and some reseal work. I listened to suggestions here. I pulled up ALL the original sealants around the roof perforations and cap junctions. I chose to use the standard Dicor self leveling sealant and the Dicor roof finish for Fiberglass. I learned that the sealant needs to dry a minimum of 1 month prior to coating with the roof coating. I did not and after 8 years under the coating it was still soft to the touch. Maybe not a bad idea. I will say I did not skimp on the quantity of material used. I used 2 and a half gallons of the white coating. In the refinish world mil thickness determines wearability and durability. I must say it held up very well, must say and minimal chalking or streaking nearly ten years later. I just sold it. Roof looked very good. 6 years ago I bought a 99 Safari Panther C 12 powered coach. It's age dictated a roof rehab on the same order of the Z despite the low miles. It is a time factor issue. Skipping to the coating. I did a lot of homework and asked a lot of questions and instead of Dicor used a product from SPI in Kansas called SuperTherm. It is used in the railcar transportation business on the roofs to drop the internal boxcar temperatures. It is a space age coating incorporating 3M's hollow ceramic ball insulation. It reflects 95% of the UV radiation solar based heat, is flexible, fire resistant and a sound deadner. It has a 20 year lifespan, blocks moisture and air infiltration. It is not necessary to keep it clean for it to work. Cheap to use no, I used 5 gallons to meet the mil thickness on a 42 foot roof, 2 coats, $400. When dry it was a flat finish. I do not like flat finishes so after fully cured painted it with 2 coats of as good a high gloss premium white white latex exterior enamel as I could find. Flat finishes collect dirt and glossy finishes repel it at a much higher rate. They clean much easier as well. This is now out 3 years AND LOOKS TERRIFIC. I wash it once year using a soft bristle broom and a little Dawn. It is definitely interesting and cooler, on a 90 degree day the roof is certainly cool to the touch, quieter, jury is still out, maybe a little. Share this post Link to post Share on other sites
wildebill308 Report post Posted August 19, 2020 I have seen them selling a spray on bedliner material for coating the roof. Lots of claims but I didn't like the rough textured finish. But they claim it last "forever". Bill Share this post Link to post Share on other sites
manholt Report post Posted August 19, 2020 Bill, one is by Armoral...that's what I had on my American Coach 45 = $4,500. Roofing jobs done by pros go from $100 to $180 a foot. Like Bill E, it took 5 weeks to totally cure after application and is flexible! We have a friend parked next to us, that had the bed liner sprayed on his front and painted to match the coach! Still looks great after 6 years, soap and water for Love Bugs & no scrubbing required...$5,000 by Iron Horse, San Antonio, TX. Share this post Link to post Share on other sites
jleamont Report post Posted August 19, 2020 6 hours ago, hermanmullins said: Joe is there a Sika product that isn't Black yes, I have seen white, black, gray and believe it or not yellow, one rental truck company spec's it to seal their cab to the body on a cutaway truck. Share this post Link to post Share on other sites
rls7201 Report post Posted August 21, 2020 On 8/19/2020 at 9:27 AM, manholt said: UV Rays will destroy white, not black! You can also paint over it...I don't care what my roof color is...I'm not up there to see it. Carl, I'm always wanting to learn more. If a black surface absorbs all colors of light and reflects no colors of light back and a white surface reflects all colors of light back and absorbs no colors of light, then why is it that UV rays only destroy white surfaces? Inquiring minds want to know. Thanks Richard Share this post Link to post Share on other sites
kaypsmith Report post Posted August 22, 2020 (edited) 2 hours ago, RLS7201 said: Carl, I'm always wanting to learn more. If a black surface absorbs all colors of light and reflects no colors of light back and a white surface reflects all colors of light back and absorbs no colors of light, then why is it that UV rays only destroy white surfaces? Inquiring minds want to know. Carl has followed many of my post's about black for some time now. Black is the only natural color that UV rays will not destroy, this is fact. When did you ever see a utility company use any other color than black wire outdoors. Now with all this said, there are additives that can be added to paint that will prevent the painted colors not be as susceptible to UV destroying them. So white does reflect while black does not but without additives the paint will chalk up and cause the white streaks that you see on the sides of RV's. So to solve this problem one can make sure that the white sealant does incorporate an appropriate UV protective additive. You asked, and I hope that this helps to understand the statement better. By the way, white is used at sea even on outside wires and antenna's, because the salt in the air and UV rays act just like chlorine and will destroy black colored wires and the like in these conditions. Just for fun, lay a black colored poly rope and several other colors including white in a location that has lots of sun on most days and see which color survives longer. I have used black rope on my antenna's over the years as well as other colors, black is still in use, all other colors 6 to 18 months and they are so frayed that they only fall apart. Edited August 22, 2020 by kaypsmith Share this post Link to post Share on other sites
jleamont Report post Posted August 22, 2020 Slightly off topic, Black trash bags do not attract birds. I believe they cannot see them or through them, not really sure but it’s nice for them not to get torn open when out front on the curb. Share this post Link to post Share on other sites
campcop Report post Posted August 22, 2020 On 8/18/2020 at 6:06 PM, TimeTraveler said: New Motorhomes have one piece roofs and don't have to have joints sealed with Dicor every two years or less... however our 05 does. It went 8 years because ti was stored inside. e had it redone this spring. Didn't cost much this time. factory was over 700.00. Surely there is a better long life sealant with UV inhibitors, that doesn't bleed all over the sides, in nasty white streaks, every time it rains???? What is it ? First off, what kind of roof is it. Fiberglass or elastomeric. On the elastomeric roofs, the white caulking is caused by the white pigment in the product . They do make products that will inhibit this shedding. on fiberglass roofs, folks have used floor wax, paint, 3m 303 spray, auto wax, etc to slow the oxidation of the gel coat. Share this post Link to post Share on other sites
urbanhermit Report post Posted August 22, 2020 16 hours ago, kaypsmith said: Carl has followed many of my post's about black for some time now. Black is the only natural color that UV rays will not destroy, this is fact. When did you ever see a utility company use any other color than black wire outdoors. Now with all this said, there are additives that can be added to paint that will prevent the painted colors not be as susceptible to UV destroying them. So white does reflect while black does not but without additives the paint will chalk up and cause the white streaks that you see on the sides of RV's. So to solve this problem one can make sure that the white sealant does incorporate an appropriate UV protective additive. You asked, and I hope that this helps to understand the statement better. By the way, white is used at sea even on outside wires and antenna's, because the salt in the air and UV rays act just like chlorine and will destroy black colored wires and the like in these conditions. Just for fun, lay a black colored poly rope and several other colors including white in a location that has lots of sun on most days and see which color survives longer. I have used black rope on my antenna's over the years as well as other colors, black is still in use, all other colors 6 to 18 months and they are so frayed that they only fall apart. Not to be argumentative, because I don't know from nuffin about this, but for totally different purposes I use POR15, a paint-like product that changes the molecular structure of rust into a rust-preventative coating. It's efficacy for that is incredible. I've only used their black color. They say it is UV degradable and must be overcoated with paint to last. ???? We bought a coach whose roof had been professionally sprayed with a granular grey product, even though the roof is one-piece fiberglass. My coach mechanic was enthusiastic about it, told me what it is, and I forgot. The previous owners said it'll never get over X degrees (forgot that, too), cool enough to walk on barefoot. I see a white sealer around through-roof features, though. Share this post Link to post Share on other sites
RVROOFINGSOLUTIONS Report post Posted August 28, 2020 There is an acrylic DIY product called 'Never Caulk' sold by Rv Roofing Solutions. https://www.rvroofingsolutions.com It's an easy process thats very user friendly. You brush down the liquid acrylic, apply a layer of polyester fabric, and coat again. It's a permanent roof seam sealant. If needed, tech support is free and available over the phone or email. Share this post Link to post Share on other sites
manholt Report post Posted August 28, 2020 It works good on houses also...for RV purpose so does RVArmor and Rhino Armor... Share this post Link to post Share on other sites
kaypsmith Report post Posted August 28, 2020 On 8/22/2020 at 12:49 PM, UrbanHermit said: Not to be argumentative, because I don't know from nuffin about this, but for totally different purposes I use POR15, a paint-like product that changes the molecular structure of rust into a rust-preventative coating. It's efficacy for that is incredible. I've only used their black color. They say it is UV degradable and must be overcoated with paint to last. ???? I've used POR15 for many years, but only on metal surfaces. It does work great on metal, I have never seen a fiberglass or rubber roof rust, yes I have seen chalking (oxidation)but not rust, I thought that rust was oxidation of iron or a byproduct thereof. Maybe I have learned something new? Share this post Link to post Share on other sites
Philipclopez Report post Posted April 15, 2021 (edited) I recently used the Dicor 501LSW-1 to recaulk my RV roof, and I’m happy to see no drop inside the RV when we had a heavy downpour the next day. Edited May 3, 2021 by Philipclopez Share this post Link to post Share on other sites
jleamont Report post Posted April 15, 2021 8 minutes ago, Philipclopez said: I recently used the Dicor 501LSW-1 to recaulk my RV roof, and I’m happy to see no drop inside the RV when we had a heavy downpour the next day. Success like that can make one smile! Share this post Link to post Share on other sites