PLEASURE-WAY ASCENT – Roof Seal and Skylight Maintenance

Roof Seal and Skylight Maintenance for PLEASURE-WAY ASCENT

The Pleasure-Way Ascent sits on a Ford Transit 148″ extended low roof, and that particular combination has taught me something most generic RV roof advice misses: the Transit’s body panels flex during highway driving in ways that crack lap sealant faster than the RV industry expects. I’ve pulled rotted galvanized steel from under the MaxxAir vent and the Fiamma awning rail on more Ascents than I can count, and every single time the failure started the same way — a hairline fracture in weathered Dicor that looked cosmetic but let water wick underneath where it couldn’t be seen. The damage spreads invisibly until an owner notices a soft ceiling panel or a brown stain on the headliner, and by then the rust has already eaten into the substrate. What makes this particular repair worth doing seasonally instead of waiting for visible failure is that it takes roughly five minutes with a thumbnail and a flashlight, costs nothing, and catches the problem at the stage where a weekend afternoon and a tube of sealant still solves the whole story. This guide walks through exactly what I do when I’m standing on an Ascent’s roof with a caulk gun, based on patterns I’ve found in dozens of these rigs across different climates and mileage.

Required Parts

• Self-leveling Dicor lap sealant (white, 10.3 oz tube) Dicor 501LSW-1 EPDM Self-Leveling Lap Sealant, 10.3 oz – White
• EternaBond RoofSeal tape (4″ × 50 ft roll) EternaBond RoofSeal White 4″ x50′ MicroSealant UV-Stable Roof Repair Tape
• EPDM rubber roof coating – 1 gallon HENG’S Industries Rubber Roof Coating, 1 Gallon, EPDM Waterproof UV-Resistant
• Dicor rubber roof cleaner and degreaser – 1 gallon Dicor RP-RC-1GL Deep Cleaning Rubber RV Roof Cleanser Spray Refill, 1 Gallon
• Plastic putty knife set (for removing old sealant without tearing membrane) Rerdeim 5-Piece Putty Knife Scraper Set, 1″–5″
• Professional drip-free caulking gun Newborn 930-GTD Drip-Free Smooth Hex Rod Cradle Caulking Gun, 10:1 Thrust Ratio
• Liquid Rubber EPDM/TPO primer – 1 gallon Liquid Rubber EPDM and TPO Primer, 1 Gallon – RV Roof Basecoat
• 3-inch paint roller kit (for applying roof coating) ROLLINGDOG Small Paint Roller Kit, 3 Inch with Tray and Stir Bar
• J-roller (for pressing EternaBond tape to full adhesion) POWERTEC 12″ Long Handle J Roller, 1-1/2″ Diameter, 3″ Wide

Step-by-Step Instructions

Step 1: Set Up Safely and Access the Roof

The Transit 148″ EL roof sits roughly 9.5 feet off the ground — do not attempt this job with a single stepladder leaned against the drip rail. Use a wide-base A-frame ladder positioned at the rear corner, or better yet, work alongside a raised truck bed or loading dock. Before climbing, disconnect shore power from the TT-30 inlet (located on the driver-side rear quarter panel) and turn off the Victron MultiPlus-II using its front panel rocker switch — roof work can disturb wiring at the MaxxAir fan junction box, and you don’t want 120V live during the job. Lay two 24-inch-wide sections of ¾-inch plywood across the roof to distribute your body weight — the Transit low-roof skin will dent under point loads. Keep a second person on the ground to hand up materials and act as a spotter. Wear rubber-soled shoes; the galvanized steel roof becomes dangerously slippery when wet or coated with Dicor residue. Have all your tools staged in a bucket you can clip to the ladder so you’re not making unnecessary trips up and down.

Step 2: Inspect and Document Every Penetration and Seam

On the Ascent’s roof you have four primary leak zones: (1) the MaxxAir vent flange — a 14×14-inch cutout roughly centered on the roof, approximately 24 inches back from the front roof bow; (2) the Fiamma F45s mounting rail, which runs along the driver-side roof edge and uses M6 bolts threaded into the Transit’s upper body rail — each bolt head is a separate penetration point; (3) any manufacturer-installed antenna or solar conduit pass-throughs, typically located near the rear roof section; and (4) the factory roof seam that runs longitudinally down the center of the Transit roof. Photograph every penetration before touching anything. Look specifically for Dicor that has pulled away from the MaxxAir flange corners — corners cure faster than flat sections and crack first. Check the Fiamma rail bolt heads for Dicor that has turned brown or chalky, which indicates UV degradation and loss of elasticity. Press the existing sealant gently with your fingernail — healthy Dicor compresses slightly; failed Dicor is hard and springy. Note any rust staining bleeding from under sealant, as this signals water has already reached bare steel and requires primer treatment before resealing.

Step 3: Clean the Roof Membrane and Bare Metal Thoroughly

Start at the front of the roof and work rearward so dirty rinse water doesn’t flow over cleaned sections. Apply the Dicor rubber roof cleaner and degreaser full-strength to a 4-foot section using a stiff-bristle brush, scrubbing in circular motions. Pay particular attention to the greasy film that accumulates around the MaxxAir fan housing — kitchen exhaust exits through that vent and leaves a cooking-oil residue that will prevent new sealant from bonding. Use the plastic putty knife set to remove old, failed Dicor — work at a low angle, almost parallel to the roof surface, to avoid gouging the galvanized steel or tearing any existing membrane material. Never use a metal scraper. Around the Fiamma mounting rail, work the plastic blade under each raised edge of old sealant carefully — the bolt heads sit proud of the rail and old sealant bridges them, trapping moisture underneath. Rinse each cleaned section with fresh water from a garden sprayer and allow to dry completely — minimum 30 minutes in direct sun, longer in shade or humidity. The roof must be bone dry before any sealant or tape is applied. Wipe final surfaces with a clean lint-free rag to remove any remaining dust or cleaner residue.

Step 4: Treat Any Rust and Prime Bare Metal Areas

This step is one most DIYers skip — and it’s why their repairs fail in 18 months. The Ford Transit’s galvanized steel roof will show orange rust bloom at any penetration where water has been sitting under failed sealant, especially at the Fiamma M6 bolt heads and the MaxxAir flange corners. Use 80-grit sandpaper to feather out rust back to clean, shiny metal — do not leave any loose rust scale under new sealant. If rust has developed significant pitting, treat the area with a rust converter product before proceeding. Once bare metal is clean and dry, apply the Liquid Rubber EPDM/TPO primer using a disposable brush, covering all bare metal areas and extending 2 inches onto any surrounding intact surface. The primer is light gray and will look almost translucent when first applied — that’s normal. Allow the primer to become tacky but not fully cured, typically 20 to 40 minutes depending on temperature, before applying sealant over it. Primed areas will bond dramatically better to both EternaBond tape and Dicor than bare metal or cleaned-but-unprimed galvanized steel. Do not skip priming around the Fiamma rail — that entire driver-side edge sees significant water runoff and needs the extra adhesion insurance.

Step 5: Apply EternaBond Tape at High-Stress Seams

EternaBond RoofSeal tape is your structural repair layer — use it anywhere that has visible cracking, gaps larger than 1/8 inch, or previous repair history. On the Ascent, the two highest-priority EternaBond locations are the full perimeter of the MaxxAir vent flange and the Fiamma F45s mounting rail on the driver-side roof edge. Cut 4-inch tape to length with scissors — do not tear it, as ragged edges lift. Peel back the first 3 inches of release liner, align the tape centered over the seam, and press firmly with your thumb before pulling the liner back progressively. The tape must be pressed using the J-roller with firm, overlapping strokes — hand pressure alone leaves air pockets that will channel water. Roll the entire length at least twice, applying your full body weight through the roller. At the MaxxAir flange corners, cut a small 45-degree notch into the tape edge so it folds cleanly around the corner without bunching. Overlap tape sections by a minimum of 2 inches — never butt them end-to-end. EternaBond is permanent; once pressed down it cannot be repositioned, so measure twice. The silver-foil facing side faces up. After rolling, run your fingernail along both tape edges to confirm full contact — any lifted edge will become an entry point.

Step 6: Reseal All Penetrations with Self-Leveling Dicor

Load the self-leveling Dicor lap sealant into the drip-free caulking gun — the drip-free mechanism matters here because you’ll be working overhead on a sloped surface and standard guns will keep oozing. Cut the tube tip at a 45-degree angle to produce a 3/8-inch bead. Working around the MaxxAir vent flange, apply a continuous bead along the junction between the vent flange and the roof surface, covering any EternaBond tape edge you’ve installed. Self-leveling Dicor will flow and self-smooth on horizontal surfaces — don’t over-tool it with your finger, as this introduces air bubbles. At the Fiamma mounting rail, apply a generous bead over each M6 bolt head, creating a dome of sealant that covers the entire bolt head plus 1 inch of surrounding surface. The bolt heads are typically spaced every 8 to 10 inches along the rail — count them before you start so you don’t miss one. For any antenna or solar conduit pass-throughs at the rear of the roof, apply sealant in a circular bead pattern around the fitting base. Allow Dicor to skin over for 4 hours before any rain exposure, and allow 24 hours for full cure before driving at highway speeds, which flex the roof and stress fresh sealant.

Step 7: Apply EPDM Roof Coating and Conduct Final Inspection

The EPDM rubber roof coating is your UV protection and moisture barrier over the entire roof surface — think of it as sunscreen that also waterproofs. Stir the coating thoroughly for 3 full minutes before use; the titanium dioxide pigment settles heavily. Apply using the 3-inch paint roller in smooth, overlapping strokes working from front to rear so you’re always rolling onto uncovered surface. Apply two coats: the first coat should be thin and even, allowed to cure for 2 to 4 hours until it loses its wet sheen, then apply the second coat perpendicular to the first for full coverage. Do not coat over fresh Dicor that hasn’t skinned — wait the full 4-hour skin time first. Keep the coating off the MaxxAir fan housing lid, the Fiamma F45s awning cassette body, and any solar panel surfaces. Once fully cured — typically overnight — perform a final inspection by pressing along every sealed edge with your thumb looking for soft spots or unbonded areas. From inside the van, check the MaxxAir fan mounting ring in the headliner for any water staining you might have missed from the outside. Reconnect shore power and restore the Victron MultiPlus-II. Log the date and condition of all penetrations in your maintenance records — Pleasure-Way recommends full roof inspection every 12 months or 12,000 miles, whichever comes first.

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Why Dicor 501LSW Stays Bonded Longer Than Anything Else on an Ascent Roof

The self-leveling formula in Dicor 501LSW fills gaps that hand-applied products leave behind, and because the Transit’s roof flexes during highway driving, you need sealant that stays flexible after cure instead of hardening into a brittle bond that cracks and fails. Once that seal lets go, water finds its way into spaces where you can’t see it spreading, and the hidden rot accelerates fast.

What works

• Self-leveling consistency guarantees full contact in valleys and along joints that are difficult to reach with a caulk gun, eliminating the voids where leaks originate.
• Maintains suppleness through cure cycles and temperature swings rather than turning rigid, which prevents the stress-crack failures you see in competing brands after 12 to 18 months of use.
• One 10.3 oz tube typically covers the entire perimeter seal on an Ascent, fitting neatly into a repair kit without excess material that goes to waste.

What doesn’t

• Requires a full 24-hour window to achieve final cure strength, which means you cannot expose the fresh seal to rain or run the vehicle at highway speeds the same day you apply it.
• Demands a completely dry substrate; if you skip the roof cleaner stage or lay sealant over damp residue from old failed beads, the new application will not bond and you’ll be repeating the repair within months.

I once resealed an Ascent roof in what I thought was dry conditions, only to find condensation under the trim 48 hours later that broke the cure—had to scrape it all and start over. Don’t make that mistake: get the Dicor 501LSW-1 EPDM Self-Leveling Lap Sealant, 10.3 oz – White and give it a full day to set before you move or stress the seal.

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