Choosing the Right Drywall for Different Rooms

Standard drywall (regular gypsum board) is appropriate for most interior walls and ceilings in dry, low-traffic spaces, but several common rooms have conditions that standard board is not designed for.

Bathrooms and other high-moisture areas need moisture-resistant board (commonly called 'green board' or 'purple board' depending on the manufacturer) at minimum behind tile in wet areas, though it is important to note that moisture-resistant drywall is not a waterproofing membrane -- in shower and tub surrounds, a proper waterproofing membrane or cement board is still required behind the tile, with moisture-resistant drywall used only in the surrounding, non-direct-wet areas.

Garages and rooms requiring fire separation from living space (a common code requirement between an attached garage and the house) need Type X fire-rated drywall, which contains glass fibers that help the board maintain integrity longer under fire exposure -- this is a code requirement in most Canadian jurisdictions for garage-to-house separations, not an optional upgrade.

Basements and other areas prone to occasional dampness benefit from mould-resistant board, which uses a fiberglass facing instead of the paper facing that standard drywall uses, since paper facing is a food source for mould growth in persistently damp conditions.

Ceilings, particularly in rooms with wide unsupported spans, may require sag-resistant board rated for ceiling use, since standard wall-rated drywall can sag over time when installed horizontally on wide ceiling joist spacing.