Building Design and Construction

To ensure adequate performance and longevity, protect metal panels from potentially corrosive situations and materials. When treated lumber will be in contact with metal panels please note: Galvanized Steel is compatible with CCA (Chromated Copper Arsenate) pressure treated lumber that is predominantly used today. Likewise, dissimilar metals also require a protective barrier between them to prevent galvanic corrosion. Plastic, builder’s felt, caulk, or gasket material may be used to separate panels from treated wood and dissimilar metals.

Condition of Substructure
Whether over solid substrate or open structural framing, panel distortion may occur if not applied over properly aligned and uniform.

Method “A”
One method for checking the roof for square ness is to measure diagonally across one slope of the roof from similar points at the ridge and eave and obtain the same dimensions.

Method “B”
The 3-4-5 triangle system may also be used. To use this system, measure a point from the corner along the edge of the roof at a unit of (3). Measure a point from the same corner along another edge at a unit of (4). Then by measuring diagonally between the two points established the dimension should be exactly a unit of (5) to have a square corner.

Fastenings
JET METALS can supply either woodgrip screws for fastening to dimensional lumber or self-drilling screws for fastening to metal. All screws with combination metal and neoprene washers should be installed in a flat area of the panel adjacent to the ribs, and lightened such that the washer is compressed as illustrated. This will ensure a lasting, leak –proof seal.

Roof Pitch
The metal roofing panels shown on this web site, require a minimum pitch of 3” per foot to ensure proper draining.

Siding
Siding should be installed using the standard fastening and overlap to ensure optimum performance. For strong neat corners use hemmed corner flashings. Do not run siding sheets all the way to the ground. Instead provide a protective base of concrete, masonry, treated wood, or similar material 12” to 18” from ground level and end the siding sheets there.

Roofing
Sidelaps should face away from wind driven rain. Therefore, begin installation by installing the first sheet square with the eave and gable at the downwind end of the roof, farthest away from the direction of the prevailing winds.