Tremco 830 field adhesion check: why primerless still needs checking
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Before you seal all the windows or siding, confirm adhesion to the materials on your job.
Primerless doesn't mean you can skip checking adhesion on your job. Tremco says Tremco 830 bonds to common construction substrates without primers, but still recommends a mock-up or field adhesion test with the materials you'll actually use. Running the field test? The data sheet points you to ASTM C1193 Appendix X1.
Don't cut or pull a test bead until you've confirmed the steps with Tremco. The sheet refers you to a procedure without giving you the instructions. Ask Tremco what's needed, then follow that procedure.
What the laboratory numbers tell you
For wood, PVC and glass, Tremco lists typical ASTM C794 adhesion values of 15–17 pli each. For aluminum, 11–12 pli. The sheet doesn't give these reported values as a pass mark for your field check.
What material faces the PVC in your window perimeter joint? Check that side as well as the PVC, and give Tremco both surface details when you arrange the adhesion check. Even if the sheet lists your substrates, Tremco still recommends testing the actual materials you'll use.
Set up the check around the joint you'll install
Write down the joint dimensions, expected surface temperature, and the materials and finishes on each side before you contact Tremco. You'll need to ask how to prepare each surface and carry out the adhesion test, plus get Tremco to confirm the cure time and what counts as a pass before you test. Always read the accompanying MSDS as well. It covers health hazards and information on Personal Protective Equipment (PPE).
Damp or contaminated surfaces? Don't apply Tremco 830 over them. The sheet says to remove release agents, existing waterproofing, dust, loose mortar, laitance, paints and other finishes. You need sound, clean, dry surfaces before application.
Tremco recommends a surface temperature of at least 5°C during application. Below that, it directs installers to its cold-weather application guide. For window and door perimeter fillet beads, the sheet specifies at least 1/4 inch of contact onto each substrate.
Don't turn this into a guessed pull test
Before you schedule the test, get the cut dimensions, pulling method, test frequency and threshold for a pass. None are given in the supplied sheet. The cure period for the adhesion check is missing too.
Making a mock-up? You still need to prevent Tremco 830 from contacting polystyrene, insulated glass seals or laminated glass.
Before you order
Does your proposed assembly need more preparation or primer? Ask that in your enquiry, along with how to judge the field check. Open the [Tremco 830 product details](/tremco-830/) and include the names and finishes of your substrates, the joint size and your planned application conditions.