MetalFormers Inc. specializes in the fabrication of all kinds of flashings, such as:
Base and counter flashings
should be installed independent of one another to allow for optimum movement. The joints should be tightly installed, but still independently.
represent the portion of the installation that is attached to the roof itself. It is "L-shaped" with one leg extended underneath the roofing material at least six inches but preferably more than that. The other leg extends up the abutting vertical surface in a perpendicular manner. In slate, tile, or asphalt shingle roofs, the base flashing may be woven into the courses of the roof sheathing; thus creating a more effective watertight joint.
are attached to the point of intersection between the roof and a wall (or a projection). This type of flashing must overlap the base flashing by at least 6 inches, if not more; thereby preventing water from seeping through this very vulnerable joint.
are used to divert moisture that has entered the wall to the outside before it can cause damage. This flashing method is considered the most preventative method of controlling leaks, except in areas exposed to earthquakes.
Roof Edge Flash Systems
Metal Roofing System
Here are some tips to ensure that your roof edge is properly installed and maintained:
Allow for thermal expansion and contraction - temperature change causes metal to expand or contract, so the roof edge should incorporate slotted fastener holes and snap-on covers that allow for thermal expansion and contraction.
Specify the proper gauge - in many cases, the metal specified for the roof edge is too light, leading to oil canning. A stronger, heavier gauge metal (ex. up to 20 gauge for galvanized steel) can prevent this problem.
Use cleats effectively - cleats are the glue that bind the roof edge to the roof surface. They need to be properly installed to meet the required wind pressures for the building.
Use proper fasteners - installing the wrong fasteners opens the way to a host of problems.
Make sure the edge provides adequate coverage -the face of the roof edge should extend at least one inch below the nailing strip to assure correct flashing. More coverage is highly recommended at a rough wall or where driven rain is common.
Consider the local environment - projects in coastal areas should never use bare aluminum or galvanized systems, as they will quickly deteriorate.