Existing buildings · Defined
Drainage plane
A layer or surface within an enclosure assembly that directs water toward an intended outlet.
Why it matters
Drainage needs a continuous path and effective discharge. Blocked outlets or poorly integrated flashing can undermine an otherwise suitable wall system. Repairs should preserve the intended drainage function, not just conceal the visible opening.
In practice
A project example
Water behind cladding cannot drain because weep openings have been sealed during maintenance.
General educational guidance from KOW Building Consultants. Examples are illustrative, not project records. The applicable contract, standard, program, and jurisdiction control the requirements for a specific assignment.