Design Considerations

Important Design Considerations

When specifying the Flashman™ Window and door Flashing Suite

See also Batten Layout Technical Drawings.

1. The Flashman window and door flashing System is only installed on a cavity. All the Flashman details are drawn with a 20mm cavity except for the 40mm Celcrete option and 40mm cavity for brick veneer.
2. If a larger cavity is required some variation is needed. Please contact Flashman 0800 55 66 00 or email This e-mail address is being protected from spambots. You need JavaScript enabled to view it for specific drawing.
3. The back of the window and door flanges must be set off 25mm from the outside face of the timber framing for 20mm cavity. If a Rigid Air Barrier is to be used the 25mm clearance is measured from the face of the RAB Board. See specific Flashman drawings for precise window offsets for various cladding types.
4. The Flashman™ flashings are installed after the aluminium joinery has been properly fitted, leveled and straightened.
5. There must be a minimal clearance of 110mm from any window or door flange at internal corners to the face of any adjacent cladding to allow the Jamb flashings to be fitted and the sill horns to extend past the vertical line of the windows. Increase this clearance to 170mm when fitting up to 100mm wide window or door facings. (The sill horns are extended 75mm either end of the sill if facings are fitted.)
6. When the Flashman™ sill is specified under external doors the cladding should extend a minimum of 100mm below the bottom plate so that the bottom of the sill does not protrude below the cladding line.
7. All battens behind the Flashman Window and Door Flashing System are installed by Flashman.