Steel lintels should always be painted before applying window sealant for several reasons:

• Protection from corrosion: Painting provides a protective layer over the steel lintel and helps prevent rust and corrosion. This is especially important in areas where the steel is exposed to moisture or harsh weather conditions.

• Improved adhesion: The paint provides a smooth and even surface for the sealant to adhere to, ensuring a secure bond and reducing the risk of the sealant separating from the lintel over time.

• Improved appearance: Painting the steel lintel before applying sealant helps to provide a uniform and finished look to the window installation.

By painting the steel lintel before applying sealant, you ensure that the steel is protected from the elements and that the window sealant is properly applied, creating a long-lasting and durable installation.