Plywood quality is hard to judge from a price list. The sheet in front of you tells you more.
Eight checks
- Marking. Branded sheets carry the brand, grade and standard on the face or edge. No marking, no confirmation.
- Flatness. Stand a sheet on its edge. Look along the face. It should not bow or twist.
- Edges. Look for tight, even layers. Big gaps or overlaps mean a poor core.
- Thickness. Measure at several points with a calliper or tape. A 18 mm sheet should not be 16 mm in places.
- Face. Look for patches, open joints and rough sanding. If the face will be visible, avoid these.
- Weight. Sheets of the same thickness that differ a lot in weight probably differ in density or core.
- Smell. A strong chemical smell can point to heavy resin or a poor product.
- Sound. Tap the surface. A hollow sound can mean voids inside.
Grade is not visible
You cannot tell MR from BWR by eye. That is why the marking and the seller's honesty both matter. Ask for the brand's marking for the grade, and compare it with the quote.
Ask the seller
- Which range is this?
- Which standard does it carry?
- Can I measure thickness?
- Is the rate per sheet or per sq ft, and does it include GST?
If a seller will not let you check these points, that tells you something.