Flashing

Function & Code Requirements

Flashings are membranes that collect water that has penetrated the exterior wythe and direct it back to the exterior. Design cavity flashing above any horizontal element that will block the downward flow of water. The 2006 International Building Code requires flashing as follows: “Flashing shall be installed at the perimeters of exterior door and window assemblies, penetrations and terminations of exterior wall assemblies, exterior wall intersections with roofs, chimneys, porches, decks, balconies and similar projections and at built-up gutters and similar locations where moisture could enter the wall.”

• Brick Veneer Flashing Requirements
• Flashing Strategies for Concrete Masonry Walls
• Flashing Case-by-Case

Flashing Types

Flashing materials include but are not limited to sheet metal (copper, galvanized steel, stainless steel, aluminum, lead), EPDM (ethylene propylene diene monomer rubber), plastics and asphalt impregnated membranes. Self-adhesive membranes are popular with many masonry designers and provide adequate durability for many applications. Copper, stainless steel, and lead flashing are used in buildings where the designed service life is measured in hundreds of years.

• Brick Veneer Construction: Advanced Flashing - Stepped Flashing, Bay Windows, and Arches
• Flashing is Key to Leak-Free Masonry

Installation

Flashings must be installed in continuous runs with sufficient overlap and adhesive at joints to prevent moisture from migrating under the flashing.

• Flashing Details for Concrete Masonry Walls

Termination at Backup

Several methods are available for terminating the flashing at backup: 1) adhering to the back up with mastic or similar adhesive. 2) securing with a mechanically anchored termination bar. 3) inserting into a cut reglet in the back up wall. 4) wrapping through a mortar bed joint in the backup.

Termination at Exterior

As per the BIA (Brick Industry Association), the flashing should slope towards the exterior and extend beyond the face of the wall ½" to form a drip.

• Projecting Flashing Beyond Steel Lintels

Flashing End Dams

End dams are used to terminate horizontal flashing runs to contain water on the flashing where it will be directed out of the wall system via weeps. Where the flashing is not continuous, such as over and under openings in the wall, the ends of the flashing should be extended beyond the jamb lines on both sides and should be turned up into the head joint several inches at each end to form a dam.

• Installing End Dams

Flashing Laps, Flashing Corners

Flashing must be continuous to work properly. As flashing is not usually installed in continuous sheets, flashing should be lapped at least 6-in. and the laps sealed with a compatible adhesive. Fold flashing at corners or use prefabricated corner elements, sealed to the flashing at each side of the corner.

• Reasons Flashing Fails

Companies Offering Flashing

Company	City	State
PROSOCO, Inc.	Lawrence	KS
Hohmann and Barnard, Inc.	Hauppauge	NY
Advanced Building Products, Inc.	Sanford	ME
Mortar Net Solutions	Portage	IN
Crown Masonry & Construction Materials, LLC	Kansas City	KS
Mutual Materials Company	Bellevue	WA
Premier Masonry & Building Supply, LLC	Martinsburg	WV
Acme Brick Company	St. Rose	LA
Chicago Block and Brick, Co.	Mundelein	IL
Gagne & Son Concrete Block	Belgrade	ME
Glenwood Mason Supply Co., Inc.	BROOKLYN	NY
MASONPRO, Inc.	Northville	MI
Masonry Accessories, Inc.	Orlando	FL
Thompson Building Materials, Inc.	San Diego	CA
Tucker-Kirby Co.	Charlotte	NC
Waldo Bros. Company	Boston	MA
Keene Building Products	Mayfield Heights	OH