A good 18 oz vinyl tarp can last for years. Most of the difference between one that does and one that doesn't is how it's handled between jobs, and how quickly small damage gets fixed.
Cleaning
Rinse off grit and road grime with water and a mild soap, using a soft brush. Skip harsh solvents and pressure washers held close; they can strip the coating. Rinse well and let it dry completely.
Drying and storing
- Never fold a tarp away wet. Vinyl itself doesn't rot, but trapped moisture grows mildew on the surface and on anything stored with it.
- Fold it the way it goes on, so the edge you need first comes off first. On a flatbed, that saves a trip around the trailer.
- Store it off the ground, out of the sun, in a bag or a box. A storage bag keeps grit out of the folds, where it wears through the coating.
Patching a tear
Vinyl tarps are repaired with vinyl cement, a solvent glue such as HH-66, and a patch of matching vinyl. The cement softens the PVC coating on both pieces so they fuse as it dries. The steps below follow the manufacturers' and sellers' instructions:
- Prep: clean both the tarp and the patch to remove dirt and oil, and let them dry. Some guides suggest lightly sanding and wiping with a cleaner.
- Cut the patch at least 2 in bigger than the damage on every side and round the corners, so they don't catch and peel.
- Apply cement to both surfaces in an even coat and let it get tacky, usually 2 to 5 minutes; check your can.
- Press the surfaces together firmly and hold, then let the repair cure, up to 24 hours, before the tarp goes back in use.
- Large repairs: one seller advises patching both sides when the patch is more than about 12 in.
Vinyl cement doesn't bond to polyethylene, so it won't fix a poly tarp; use tarp repair tape on those.
Grommets and D-rings
A grommet that tears out usually takes the hem with it. Patch the corner on both sides first, then set a new grommet through the patch. D-rings on flatbed tarps are stitched to webbing; if the webbing frays, have it re-stitched before the ring lets go on the road.
Why sun and heat age vinyl
A vinyl tarp is flexible because of plasticizer blended into its PVC coating. Heat and ultraviolet light slowly drive plasticizer out of the surface, and as it leaves, the coating stiffens; at the end of that road it cracks when flexed. You can't stop it entirely, but storage makes a real difference. A tarp stored folded in a hot truck box in full sun ages much faster than one stored rolled in the shade. Keeping it clean helps too: grit worked into the folds abrades the coating every time the tarp moves.
Why vinyl cement works
Vinyl cement isn't a glue that sits on top of the surface. It's a solvent-based cement that softens the PVC coating on both the patch and the tarp. When the two softened surfaces are pressed together and the solvent evaporates, the PVC chains from both sides are tangled together in one layer, which is why a good patch can be as strong as the tarp around it. It's also why the surfaces have to be clean: oil and dirt keep the solvent from reaching the PVC.
Sources
- Mytee Products, HH-66 vinyl cement tarp repair guide (PDF)
- Carolina Tarps, vinyl cement tarp glue HH-66
- Greatmats / Mancino, vinyl repair kit instructions (PDF)
- Q-Lab, accelerating plasticizer migration testing in PVC
Written by the TrueTarps team. Questions about your job? Contact us or request a custom tarp.