Half-storey knee walls: air, insulation and ventilation

One-and-a-half/two-and-a-half-storey homes have several small attic zones where air leaks and insulation discontinuities are easy to miss.

Decision triage

VERT / GREEN · JAUNE / YELLOW · ROUGE / RED

What the professional checks

The professional checks the enclosure plane, knee walls, joists below walls, roof slope, air/vapour control, small-attic ventilation and moisture signs.

Official sources

Sources checked: 2026-08-24