Tuesday, November 28, 2023


We tried an RV roof coating — Here’s our six-year report

By Russ and Tiña De Maris

EPDM rubber is a persnickety product. The use of petroleum-containing chemicals or citrus-based cleaners on a rubber roof is to ask for swelling and deterioration. Use the “wrong” kind of coating and you’ll reap a similar result. There are few coatings that are truly safe (or even effective) for use on an RV’s rubber roof. Among them are Dicor’s Roof Coating System and Heng’s Rubber Roof Coating. A quick glance at the roof coating section at the hardware store will show there are other products that “look” like they may do the job. Read the fine print carefully – you’ll find most specifically tell you NOT to use their product on a rubber roof.

Even if the product you look at isn’t specifically ruled out for use on a rubber roof, take note of these factors: An RV roof coating needs to be elastomeric, meaning having the elastic properties associated with natural rubber. Rubber roofs expand and contract with heating and cooling. Any coating you add to the roof must likewise do the same, otherwise it will simply crack and break off.

Additionally, since many RV roofs have little pitch and may even have areas where water collects (called “ponding”), whatever coating used must resist ponding. A popular product called “Snow Roof” can supposedly be used on EPDM roofs, provided their brand of primer is first applied. Elsewhere on the label you’ll find a warning that the stuff can’t be used on a flat roof. Plenty of older RVs have a dent in the roof near the air conditioning unit where water effectively ponds and won’t run off.

Back in 2011, we were faced with the issue of “coating” our elderly travel trailer’s roof. After doing a lot of research, we decided to try the Heng’s product. Here’s what we wrote about the subject, shortly after we put the stuff on the roof. We’ll tell you how things have shaped up in the six years since we treated the roof – down farther in this article.

Here’s a step-by-step on how we used Heng’s Rubber Roof Coat to recoat an aging travel trailer roof:

1. Prepare the surface. Use a scrub brush and a bucket of soapy water. CAREFUL! Heng’s tells us it’s extremely important to use the right kind of soap. They recommend a solution of Tide powdered laundry detergent mixed with water. DON’T use Dawn dishwashing detergent – if you do, the Heng’s may later peel off. Scrub the roof fore-and-aft, rinsing with plenty of water. Allow the roof to dry completely.

2. If there are tears or punctures, we recommend fixing the damage with EternaBond roof repair tape.

3. Apply a base coat of Heng’s following the instructions on the can. While Heng’s says you can thin its product, we don’t recommend it. The thinner it is, the less likely you’ll have the best protection. We use a short-nap paint roller, applying the coating at a rate of about a gallon per 200 square feet of roof surface. You’ll find a paint brush invaluable for working around a/c units and around edges. A rag can be used to wipe up drips before they dry.

4. Allow a minimum of four hours’ dry time before sticking on a second coat. The roof we did most recently was on a 14-year-old trailer and while the roof had no damage, it was decidedly getting thin. We opted to put on a second coat to enhance our feelings of security. Don’t apply a single thick coat; you’re much better off with two thin ones.

As to cost, we were out about $110 for materials and supplies, having paid a little less than $50 a gallon for the roof coating. In the end, we had a half-gallon of the Heng’s left over which we kept for doping seams in the future.

So here we are in 2017 – six years after we coated our roof with Heng’s. How did it go?

From our perspective, Heng’s has really stood the test of time. One-half of our team braved the extension ladder for a roof inspection and maintenance tour. We found a couple of seams that needed to be coated – and that wasn’t the Heng’s that was at issue, it was a transition between the rig’s front cap and the rubber roof. Another area requiring attention was the sealant around the roof vents. No surprises here – this is a regular maintenance issue for all RVers.

As far as the roof itself – the Heng’s was still thoroughly “stuck on” the original EPDM rubber roof like a barnacle to a ship’s hull. It was decidedly tight, free of cracking, and oddly enough, still fairly white (and hence heat reflective) after six years baking in mostly Arizona sunlight, and with no scrubbing or washing in the interim. We compared this with an OEM EPDM rubber roof on our big park trailer. In the six years since we put the Heng’s on the traveling rig – the park trailer’s original roof had begun a definite change to a brownish color. Looks like it’s time we treat that roof!

No complaints! We’ll use Heng’s the next time we need to treat a roof. And when we buy our next batch, it doesn’t matter if we buy the can with the blue label, or the one with an orange label. If it says, “Heng’s Rubber Roof” it’s the same stuff, orange or blue. The big park trailer, yep, probably will see a dress up with Heng’s this fall. The travel trailer? It may have a new owner long before it needs another roof coating!


Russ and Tiña De Maris
Russ and Tiña De Maris
Russ and Tiña went from childhood tent camping to RVing in the 1980s when the ground got too hard. They've been tutored in the ways of RVing (and RV repair) by a series of rigs, from truck campers, to a fifth-wheel, and several travel trailers. In addition to writing scores of articles on RVing topics, they've also taught college classes for folks new to RVing. They authored the book, RV Boondocking Basics.



4 1 vote
Article Rating
Subscribe to comments
Notify of

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Oldest Most Voted
Inline Feedbacks
View all comments

Don Baxter (@guest_219273)
10 months ago

Some websites state the Geocel Proflex Rv roof repair can be used on an epdm rubber roof .This does not seem to be the case on other sites . I went to an rv dealer where I bought our trailer and was told not to use the Geocel product on our roof

David Mowan (@guest_202516)
1 year ago

I have tried Heng’s Roof Coat Orange Can after scrubbing with powdered soap and bleach on a 14 year old roof .I used 2 gallons on 8×11 roof section and 3×18 slide out multiple coats awesome white color. Inside temperature 100% cooler I have 2 more gallons to finish the rest of my 40 ft roof and 3×7 slide out . Now the test of Time will tell

John (@guest_194265)
1 year ago

Did you use the blue can, which is polyurethane foam, or the orange can? I know that the orange will work on my EPDM roof, but am wondering if I can save a few bucks with the blue can?

Michelle Arntt (@guest_86977)
3 years ago

I have a steel horse trailer/camper that I want to put a rubber sealant on, right now it just painted and has some surface rust. Will this product work and what do I need to to prep.

Ron davis (@guest_47682)
4 years ago

When using the Hengs Liquid Roof RV Roof Coating ( Orange Can ) did you have to use a primer before you applied Hengs Liquid Roof RV Roof Coating ( Orange Can ) ?

Richard (@guest_78567)
3 years ago
Reply to  Ron davis

No primer required with Heng’s – just a good scrubbing.

Bob Haas Jr (@guest_78967)
3 years ago
Reply to  Richard

True, just remember not to scrub with Dawn before applying, because the article said they warned about doing that because Dawn can weaken the bond of Henry’s to the roof. Makes sense, putting a drip in a greasy pot of water you can see how it repels the oils immediately. They recommend scrubbing with a solution of Tide and water.

Dwight Wuerth (@guest_40047)
4 years ago

I was happy to read your report on Heng’s rubber roof coating I just finished re-coating My majestic class c RV. It was so easy to do and believe me at 69 years old and three artificial joints. It cold have been a task. BRGDS DEW

Peter (@guest_11949)
6 years ago

Has anyone tried Flexseal, it has done good by me on a 1995 Georgie Boy roof that had a leak for years and was border line in need of new under plywood.
I coated it with two thin coats after washing with Mr.clean, then flex taped all joints that had failed and I trimmed. Then the two coats on top of that- no problems so far.

Richard (@guest_78568)
3 years ago
Reply to  Peter

I’ve heard Flexseal is NOT compatible with most rubber-tyle RV roofs. Just saying…

Bob Haas Jr (@guest_78968)
3 years ago
Reply to  Peter

I read liquid flex seal says it is not for roofs. I don’t think it has the UV inhibitors like Henry’s, so you risk having flex seal dry out and crack over time. RV roofs get intense exposure to sun, so why risk it. Otherwise I’ve been impressed with flex seal tape and liquid where sun damage isn’t a concern.

Bob Haas Jr (@guest_78971)
3 years ago
Reply to  Bob Haas Jr

Sorry folks, I just checked and now Flex Seal does have UV inhibitors and is recommended for roofs, including RV’s and trailers. 5/2020 Amazon has a 1 gal. at $90 vs. Hengs at $60.

Rocky Burrous (@guest_7553)
6 years ago

Googed the product, but have seen two different colored cans.
What is the difference between the orange can and the blue can?

Robert Dike (@guest_7819)
6 years ago

In your article you mention “An RV roof coating needs to be elastomeric”. Neither orange or blue can says “elastomeric” however there is a product that does. “Hengs Industries 471284 Elastometric Roof Coating”. The green can says INDUSTRIAL USE ONLY. Is the green can a better product for the EPDM roof?

Penny Heist (@guest_7518)
6 years ago

I’d like to see a report on the roofs recovered with rhino-liner or similar product. I wonder how much weight it would add to your GVWR and how well it stands up to traveling. I know my truck bed liner is faded but still good.

Rick Myers (@guest_7417)
6 years ago

I just ordered some from Amazon, to coat a friends roof. I coated my 5th wheel roof three years ago with good results.

Ron Schmitz (@guest_7400)
6 years ago

I have a 2016 class A with a TPO roof and was reading internet about differences in TPO & EPDM roofs. Most articles state TPO roofs fail in high heat & high exposure to sun light, but thats what an RV is exposed to most of the time. Is this true and if so why do RV manufactures use it? How long would a TPO roof go before needing to recoat it?

Bob Haas Jr (@guest_78970)
3 years ago
Reply to  Ron Schmitz

EPDM is black with a white coating that chalks and wears off over time. TPO is a newer product, white all the way through, and stronger so many manufacturers use the cheap thinner 20 mil TPO, like Super Flex, which lasts past their RV warranty period. They are all about keeping manufacturing costs down. In comparison places like rvroofinstall.com boast on Youtube about using a 60 mil TPO, but I haven’t seen that available for DIY. I did find 45 mil TPO, available with RV/trailer roofing kits at prices similar or less than the twice as thin Super Flex kits at LottesRoofing.com 35′ kit is only $533 no tax and free shipping in the lower 48 states (5/2020).
https://store.lottesroofing.com/white-45-mil-tpo-rubber-roof-complete-installation-kit-10-x-35-350-sqft-free-delivery-48-states I’m considering this vs. coating with Henry’s, but I have to replace some trusses and plywood, and the thin TPO on now will be hard to reapply. Might just redo it all!

Ron Story (@guest_7379)
6 years ago

Where can I get some of that Hengs rubber roof? I live in Eugene,Oregon.

RV Staff
6 years ago
Reply to  Ron Story

Hi, Ron —
Here’s the Amazon link to the Heng’s products (also linked in the article): https://amzn.to/2q9Mhte Or check online for a store near you that carries it. Thanks for asking. —Diane at RVtravel.com

Sign up for the

RVtravel Newsletter

Sign up and receive 3 FREE RV Checklists: Set-Up, Take-Down and Packing List.