Metal Roofing & Flashing
Standing seam, flat seam, copper roofing, step flashing, counter flashing, drip edge, and gutter fabrication.
- Describe standing seam, flat seam, and batten seam roofing systems
- Fabricate step flashing, counter flashing, and drip edge
- Design and install gutter systems and downspouts
Lección 1
Standing Seam Metal Roofing
Standing Seam Systems
Standing seam metal roofing is the premium sheet metal roofing system. The seams stand vertically above the roof surface, keeping the fasteners and seam above the water line. Panels run from ridge to eave with no horizontal joints (for standard length roofs). This design makes standing seam roofing extremely weather-tight.
Single-Lock Standing Seam
Seam height: 1" to 1-1/2"
Closure: One fold-over
Tool: Hand seamer or roofing tongs
Application: Steep slopes (4:12+)
Double-Lock Standing Seam
Seam height: 1" finished
Closure: Two fold-overs (watertight)
Tool: Mechanical seamer or hand seamer
Application: Low slopes (2:12 to 4:12)
Panel Clips
Standing seam panels are attached to the roof deck using concealed clips. The clips are fastened to the deck, and the panel locks over the clip during seaming. This allows the panel to expand and contract with temperature changes without stress on the fasteners. Fixed clips hold one point of the panel stationary while expansion clips (also called floating clips) allow movement.
Thermal Expansion
A 20-foot aluminum panel can expand nearly 1/2 inch from winter to summer temperatures. All standing seam systems must accommodate thermal movement with expansion clips and relief points. Fixed clips go at the top (ridge) and expansion clips cover the remaining length.
Flat Seam Roofing
Flat seam (also called flat-lock seam) roofing uses interlocking panels laid flat on the roof surface. Each panel is folded on all four edges and locked to adjacent panels. Flat seam roofing is used on low-slope or flat roofs and for copper roofing applications. Each panel is soldered at the seams for waterproofing.
Standing seam roofing has vertical seams above the water line with concealed clips for weather-tightness. Double-lock seams are required for low slopes. Expansion clips accommodate thermal movement - fixed clips go at the ridge, expansion clips along the panel length.