As well as creating a waterproof seal, they can also add to the finish of the roof, creating seamless lines and joins between sheets, tiles and wall edges. Here we discuss the various types of flashings available, why they're required, and where to install them depending on the type. Install counterflashing in reglets, either by snap-in seal arrangement, lock seal in accordance with the "Copper in Architecture" handbook published by the Copper Development Association (CDA) , or by soldering in place for anchorage and filling reglet with mastic or elastomeric sealant, as indicated and depending on degree of sealant exposure. Underlayment: Where installation is to be directly on cementitious or wood substrates, install red rosin paper slip sheet over layer of asphalt saturated felt. Special Conditions: Copper counterflashing may be used in conjunction with copper base flashing and composition base flashing for built-up roofing.

Unless your continuous flashing has built-in expansion joints, they can have trouble flexing and can break/crack with these house movements. A reglet is used to hold the continuous cleat in place, thus eliminating the need for wood blocking. Expansion joints should be provided for long runs of metal flashing to allow movement without causing deformation. There are different terms given to flashing, often determined by where they are used or their shape. It is also used to divert to the exterior moisture that has already entered various components of a structure.EDIT EXAMPLES BELOW BY DELETING ITEMS NOT REQUIRED, ADDING OTHERS, OR REVISING TEXT TO CLARIFY DESCRIPTIONS. The top of the roof pan is formed into a "bread pan" whose upper edge is just above the finished batten. Fabricate as indicated on Drawings and in accordance with the CDA "Copper in Architecture" handbook. Such a system usually consists of copper counterflashing and base flashing in conjunction with roof composition flashing or coping.

Cold rolled copper is recommended rather than soft copper as it offers more resistance to expansion and contraction stresses, although soft copper is useful where there are complex roof shapes.The ends of the flashing must be dammed to prevent water that has been caught from draining back into the wall. If your flashing is damaged, you can bet that it has sustained the same weather damage that your shingles have. The nail should be driven just above the upper edge of the flashing, allowing its wide head to hold the copper sheet.