Campervan Window Bonding: The Complete Guide

winbond-int
1 day ago
3 min read

Fitting bonded windows is one of the most transformative jobs in any campervan conversion - and one of the most nerve-racking. Cut a hole in your van, bond a pane of glass into it, and there's no going back. The good news: with the right adhesive system and preparation, a bonded window is stronger and better sealed than the metal you removed. This guide walks through the products and the process the trade uses, from a company that has supplied windscreen fitters and converters since 1998.

Choosing your adhesive

Winbond Sixty HV Primerless is our converters' favourite. It's a hybrid SiMP adhesive - solvent and isocyanate free, virtually odourless - that bonds direct to glass, painted metal, GRP and most plastics with no primer needed. Fewer steps, fewer consumables, and it's crash-tested (TUV, FMVSS 212) with a 1-hour drive-away time. If you're fitting acrylic conversion windows or bonding GRP panels as well as glass, this is the one.

Winbond Ultracure is the classic professional windscreen route: a fast-curing, high-modulus 1-part polyurethane used with the Combo Glass/Paint Primer system. Slightly more preparation, maximum-proven windscreen pedigree (FMVSS 212, 1-hour drive-away, dual airbags). Choose this if you're doing screens as well as side glass, or prefer the traditional primed PU system.

Either way, the easiest route is a bonding kit - everything for the job in one box: adhesive, nozzles, wipes, gloves and instructions (primer and applicators in the Ultracure kits). Single kits do one window; double kits do a pair in one session.

Surface preparation (where windows are won and lost)

Clean. Substrates must be clean, dry, dust- and grease-free. Wipe the bonding faces with Winbond Glass Wipe - it degreases and chemically activates glass and non-porous surfaces in one pass. Wipe on, wipe off after 30-60 seconds.
Prime (Ultracure system). Shake the Combo Glass/Paint Primer until the agitator ball rattles, then 30 seconds more. Apply a thin, even black film to the glass frit band and any bare or scratched metal on the aperture. It promotes adhesion, blocks UV and stops rust creeping under the bond. Dry 10-15 minutes; bond within the hour. (Skip on most substrates with Sixty Primerless - test first on unusual plastics.)
Bare metal edges. Cut edges of the aperture should be de-burred, painted or primed - the primer doubles as a corrosion inhibitor on nicks and scratches.

Find Glass Wipe and Combo Glass/Paint Primer in primers and solvents.

Bonding the window

Dry-fit first and mask around the aperture for a clean finish.
Apply the adhesive in a continuous triangular bead (roughly 8-10mm) around the window or aperture flange - no gaps, and overlap the start point.
Fit the glass within the adhesive's skin time (about 15 minutes for Sixty HV and FC205/HMLC; up to 25-40 for Ultracure - check your TDS), press home evenly and tape or support it while it cures.
Cure rate is roughly 3-4mm per 24 hours at room temperature. Keep the van still and doors closed gently for the first day; full strength follows over the next few days.

Sealing seams, arches and roof vents

For everything that isn't glass - floor seams, wheel arches, roof vent flanges, cable glands, panel joints - use Winbond PUR Sealer (PU 50): a single-component PU adhesive/sealant with >700% elongation, excellent weather resistance, and it's overpaintable when cured with water-based paints. The campervan gap-filler.

Finishing touches

Neaten cut panel edges and window apertures with our U-shaped edge trims (1mm-12mm panel thicknesses, including the purpose-made VW T4 side window trim). See the full trims and profiles range.

FAQs

Do I need to remove the paint where I bond? No - bond to sound, clean paint. Prime scratches and bare metal.

Can I bond acrylic windows? Yes - Sixty HV Primerless bonds acrylic (PMMA); test-fit first and follow the TDS. Leave expansion clearance around acrylic panes.

How soon can I drive? Drive-away times (1 hour for Ultracure/Sixty HV) are crash-test benchmarks; for conversion windows, we suggest leaving the tape on and the van still overnight.

How much adhesive per window? A 290-310ml cartridge does one typical van window with some to spare; a double kit does a pair.

Where are the datasheets? All TDS and SDS downloads are in our datasheet library and on the Technical Resources page.

Questions mid-build? Call the technical team on 01455 559889 or email sales@winbond-int.com - we've talked hundreds of first-time converters through their first window.