Designed to carry the full load of wet masonry as soon as they are installed, Keystone Box Lintels feature perforations along their length to provide a plaster key. Insulation can also be provided as an optional extra.
Box lintels must have a minimum end bearing of 150mm on each side of the opening and be bedded on mortar. The lintel should be level along its length and across its width.
Masonry must be laid on a mortar bed, with all perpendicular joints fully filled with mortar. Care should be taken to avoid shock loading on box lintels when used in conjunction with concrete floors or other heavy units.
