Lintel specification and placement for damp protection
What it looks like
Incorrect lintel material choice or insufficient projection, leading to premature corrosion or water ingress above windows.
Why it happens
Lintels in external masonry must be appropriately specified, such as austenitic stainless steel in aggressive environments, and correctly positioned. The external edge of the lintel should project sufficiently beyond the window head to shed water effectively and protect the opening from driving rain, especially in high-exposure areas where separate cavity trays are mandatory.
What it costs if it is missed
Lintels in external masonry must be appropriately specified, such as austenitic stainless steel in aggressive environments, and correctly positioned. The external edge of the lintel should project sufficiently beyond the window head to shed water effectively and protect the opening from driving rain, especially in high-exposure areas where separate cavity trays are mandatory.
How to inspect for it
Verify lintel material is correct for the exposure zone and that the lintel projects adequately to protect the window head.
How to prevent it
Lintels in external masonry must be appropriately specified, such as austenitic stainless steel in aggressive environments, and correctly positioned. The external edge of the lintel should project sufficiently beyond the window head to shed water effectively and protect the opening from driving rain, especially in high-exposure areas where separate cavity trays are mandatory.
Basis in regulation
BS 8103-2
Read the source
Last updated 23 August 2026. This is our editorial summary of publicly available regulation and site practice, not building control approval or a warranty determination.