What does RTD mean on plywood?
RTD is a manufacturing designation for CDX-grade structural sheathing bonded with an Exposure 1 adhesive. The commonly cited reading of the letters is "Resistance Temperature Detector," a reference to the temperature-controlled hot-press route used to cure the glue-line. Treat that as the prevailing industry explanation rather than a settled technical fact. In practice RTD is ordinary softwood sheathing, the same veneer grades and bond class as CDX.
Is RTD plywood the same as CDX?
Essentially, yes. RTD and CDX share the same C/D veneer grades and the same Exposure 1 glue class, and both are used for wall sheathing, roof decks, and subfloor. The difference is the drying and pressing route, not the grade. RTD is not a higher or stronger tier of plywood than CDX.
Is RTD plywood waterproof?
No. RTD carries an Exposure 1 bond, which is water-resistant enough to survive the weather a jobsite sees before the building is closed in, but it is not waterproof and not built for standing water or permanent wet service. For wet-service work such as docks or boat building, a marine-grade panel with a fully weatherproof phenolic bond is the correct choice.
Is RTD plywood pressure-treated?
No. Pressure treatment is a separate chemical process applied after the panel is made to resist rot and insects. A standard RTD sheet has not been treated. For ground-contact or exposed applications that need rot resistance, buy a pressure-treated panel as such.
What is RTD plywood used for?
RTD is used for the everyday structural work of a wood-frame building: exterior wall sheathing, roof decking, and subfloor. It fills the same role CDX has for decades, tolerating construction-stage weather exposure thanks to its Exposure 1 bond.
