Can you use DPC as a cavity tray?
High Bond DPC can be used for cavity tray applications including parapet walls, beneath copings and cappings. High load DPC should be used where it will be subject to a full storey of masonry. At complicated junctions, clear drawings and the design should be provided, and preformed cavity trays used.
Do you need DPC and cavity tray?
There isnt normally a cavity tray at dpc level, unless in instances where the likes of a Radon Barrier is required, which should overlap inner wall, cavity and outer wall. You would then need a cavity tray above with weep holes.
Are cavity trays necessary on a rendered wall?
Cavity trays are required at all roof abutments. Preformed stepped cavity trays should be provided at raking abutments with a weephole at the bottom tray. A site made or preformed cavity tray should be provided at horizontal abutments with weepholes at maximum 1m centres.
Do cavity trays work?
They are lightweight, simple to install and long-lasting solutions to the prevention of damp from penetrating below the roof line. This works by stepping up between the outer and inner leaves, to form a gutter which leads to a weep vent in the outer leaf.
How do you fit cavity wall trays?
Cavity trays should be installed over all external door and window openings including bay windows and at roof abutments, both horizontal and pitched. The cavity tray should be correctly located directly over the window/door head. Purpose-made stepped cavity trays are best utilised for all pitched roof abutments.
Do you need weep holes in a cavity tray?
Preformed cavity trays Whichever cavity tray construction is used, weepholes are required. At least two weepholes must be provided to cavity trays above openings and pre-formed “weeps” should always be used at maximum 900mm centres and always be positioned at stop ends.
Do I need weep holes?
Though homeowners naturally want to block pests, weep holes should not be sealed with caulk or mortar. The holes are still necessary to drain water and to ventilate the air space.
Do old houses have cavity trays?
Cavity trays were not always used at the heads of openings. On many older houses they have been added subsequently. Look for tell tale signs, usually a few new courses of brickwork over the lintel.