What is HDO plywood?
HDO plywood is a concrete forming panel with a resin-impregnated fibre overlay hot-pressed onto one or both faces. Overlay grade, not thickness alone, sets abrasion life, concrete finish, and how many pours the sheet can carry. Vinawood ships the APA-style ladder as HDO Basic, HDO Premium, and HDO Premium HD on a plantation-grown hardwood core with WBP phenolic bond (EN 636-3 / Class 3). The overlay is part of the pressed panel build, not a brush-on coating.
What is the difference between HDO and MDO plywood?
HDO uses a high-density fibre overlay that casts a glossy, closed concrete face for architectural pours. MDO as a search term covers two different things: APA kraft-paper panels for paint and signage, and matte phenolic formwork buyers still search as MDO. Vinawood's formwork answer in that search cluster is MatteFace Plywood - a matte phenolic surface film, not kraft paper and not a paint-grade sheet. Soft bridge only: write MatteFace on the RFQ when the drawing wants matte; keep HDO when the finish is glossy.
How many times can HDO plywood be reused?
Vinawood rates HDO Basic at up to 10 reuse cycles and HDO Premium and Premium HD at up to 20. Those are maxima under correct site practice - thin release agent every pour, clean while residue is soft, seal cut edges, and store flat under cover - not a guarantee on the packing list. Never quote 25, 30, or 50+ on a Vinawood HDO leaflet. If a job needs more than about fifteen rotations from the same sheets, Premium or Premium HD is usually cheaper by project end even when the invoice is higher.
Is HDO plywood waterproof?
No. HDO is water-resistant, not waterproof. The overlay sheds water and resists abrasion, and Vinawood HDO is WBP phenolic-bonded (EN 636-3 / Class 3). Cut edges still wick moisture into the core if left unsealed. Seal every site cut and keep stacks under cover between pours.
Is Vinawood HDO phenolic Class 3 - and how is it made?
Yes. The Vinawood HDO range is WBP phenolic-bonded and Class 3 under EN 636-3 on a plantation-grown hardwood core. Overlay grade (Basic vs Premium vs Premium HD) still decides abrasion life and cycle count - bond class alone does not set reuse. Form Extra is Superior Glue MUF EN 636-2 and is not Class 3. Vinawood has manufactured formwork plywood since 1992 through a 12-step process with 100% individual sheet inspection, shipping about 5,000 containers a year to 55+ countries.
Where do contractors buy mill HDO packs vs retail sheets?
HDO for repeating glossy formwork belongs on a mill pack or distributor-ready stock with mill test reports and product leaflets - overlay grade, EN 636-3 bond, thickness, and reuse written as up to N. Big-box and lumberyard aisles sell cut sheets for one-off pours; grades, docs, and reuse are often missing. Ask for the grade leaflet and mill docs before you compare price-per-sheet. For factory-direct RFQs start at the quotation form, and pair the type ladder with what formply is used for.
