Good weathertightness design is based around the four Ds of deflection, drainage, drying and durability.
Flashman Flashing Systems Ltd believes there is an all important 5th “D” — Do-ability.
Conventional construction drawings of flashings including those that appear in the compliance documents of the New Zealand Building Code are almost always only two dimensional. These limited view drawings fail to present a realistic depiction of the all important junctions.
The general unavailability of proprietary, prefabricated flashings often results in poor flashing practice on site. As a consequence, leaks around windows and doors are still a common occurrence.
Tradesmen are no longer trained (like plumbers were) to fabricate suitable flashings on site, and this is one of the major reasons why Flashman Flashing Systems Ltd was formed.
Mike Anticich, one of the two founding directors of Flashman, owned a private building inspection company for 14 years and was heavily involved in building surveying and weathertightness assessment before selling the thriving business in order to join forces with a well respected master builder and project manager Steve Hotton.
Fifty percent of leaks in leaky buildings occur at the windows and door junctions. So the two men resolved to find a solution to this troublesome leakage problem.
After four and a half years of dedicated research, the Flashman window and door flashing system has succeeded in solving the leaky window to cladding junction problem.
The company has designed, researched, tested and manufactured a highly innovative all-extruded aluminium window and door flashing system to fit around aluminium joinery. The flashings are precisely fabricated in the factory and then installed by technicians on site.
The BRANZ-appraised system has been fitted to a number of full and partial re-clads over the past two years before release to the general market.It was tested in 180kph wind and rain weathertightness booths, has a serviceable life of 50 years and carries a 10-year installation warranty and a 15-year product warranty.
The system is fully supported by James Hardie Ltd, Rockcote Systems and Nu-Wall aluminium cladding who have given their full approval for this robust method of flashings when used in collaboration with their range of claddings.
The most difficult part of the design process was to get the junctions right so that they simply would not leak but allowed easy fabrication and on-site installation, while also presenting an aesthetically pleasing appearance.
The principle of the system is to express all water by superior deflection to an external extruded aluminium sill which also provides full support to the bottom edge of the cantilevered aluminium joinery, preventing sagging, stress and, ultimately, leaks at the window mitres.
The jamb section is cleverly designed to maintain a recessed look but does not require plaster around the vertical sides of the window, making the plasterer’s job quicker and easier.
There is no requirement to fit scribers when using Linea or timber weatherboards. The jamb design therefore significantly lowers the cost of installing these claddings.
The head of the window or door is protected by a one-piece cavity head flashing which includes a cavity closure and, therefore, avoids the often messy junction that occurs when conventional two flashing systems are used.