Keene Building Products and Architectural Testing Incorporated conducted a masonry cavity wall mortar collection product comparison. The test measured the air flow performance of the Keene Driwall™ Mortar Deflection 1.0-075 and a dovetail product (Product A).
A 5’ by 10’ steel channel frame was constructed to support the wall during the test comparison. A stud wall was fabricated, fastened to the steel frame and sheathed with polycarbonate. Three ounce copper fabric flashing was used at the base of the wall and provided coverage twelve inches up the polycarbonate sheathing. The wall was constructed by a masonry contractor who used standard modular bricks with a smooth face and keystone type N mortar.
After the flashing and first course of bricks were laid, the mortar collection device was placed into the one inch cavity the full width of the wall. The entire wall was then constructed with three weeps at both the sill and the head.
The test method was as follows:
Air Infiltration: ASTM E 283-04, Standard Test Method for Determining the Rate of Air Leakage Through Exterior Windows, Curtain Walls, and Doors Under Specified Pressure Differences Across the Specimen. Testing was conducted at 1.57 psf (25 mph) and 6.24 (50 mph) positive static air pressure difference.
Test Results:
Keene Driwall Mortar Deflection 1.0-075
25 MPH 50 MPH
29.9 CFM 64.1 CFM
Product A
25 MPH 50 MPH
15.8 CFM 37.9 CFM
After reviewing the test results, the Keene Driwall™ Mortar Deflection 1.0-075 allows for significantly more air flow in the cavity wall over Product A.
Properly draining and ventilating a brick veneer wall is essential for its longevity. The Keene Driwall™ Mortar Deflection products are key when trying to accomplish both drainage and ventilation. When specifying any of the Keene Driwall™ Mortar Deflection products, you are assuring that the weep holes stay unclogged and any incidental moisture that penetrates the wall will be able to escape to the exterior. The wall will also be able to ventilate which is a crucial component for drying out the wall.