ONDURA-6V ™ Corrugated Asphalt Roofing Sheets I N S T A L L A T I O N I N S T R U C T I O N S
Thank you for choosing ONDURA-6V for your roofing project. ONDURA-6V should be carefully installed. Mistakes in installation can cause roof problems later on. Please take your time and closely follow these installation guidelines. CAUTION Installation of roofing materials can be dangerous. The relative amount of danger is increased by the height from the ground, increasing pitches of the roof slope, inclement weather conditions or other factors.
Note: At the ridge of the roof the gap across the ridge, between the upper ends of the ONDURA-6V sheets on each side of the roof, will be covered by the ridge cap; and the gap should be no more than two inches. PLANNING STAGE Determine the Slope of the Roof The slope of the roof can be calculated from measurements of the rise and run of the roof. The rise is the vertical distance of the ridge above the eave. The run is the horizontal distance of the ridge from the eave.
Placement of ONDURA-6V Sheets If more than one row of ONDURA-6V sheets is needed, then the sheets must be installed along the eave first. Then additional rows are installed above the previous row. Each row should be installed with the first sheet at the opposite end of the roof from the prevailing winds. With this orientation, the seam of the overlap will face away from the prevailing winds. This orientation will reduce the possibility of wind-driven rain getting under the corrugation overlap.
Drive each ONDURA nail only through the crown of a corrugation and perpendicular to the roof surface. Be careful not to overdrive or underdrive the nail. The rubber washer on the nail should be snugly in contact with the sheet. Slight hand pressure on a nailed-down corrugation should not separate the sheet from washer contact. Valley Flashings For valleys, install a minimum 24˝wide metal valley flashing.
Slope Changes Ondura-6V Rake Trim Flashing width should be increased as slope differences increase or whenever water build-up on the lower slope can be substantial. Finish your rake edge with metal flashing, either over or under the last corrugation edge of the ONDURA-6V sheet. When using metal flashing under the last corrugation, be careful to avoid nailing through your flashing. Deck Eave closure strip sheathing placement Use elastometric caulking at all flashing joints and closure strips.
Ridge Cap Note: Install all sheets on both sides of the roof before installing the ridge cap. Measure the ridge to determine the required coverage. Ridge caps are available in 39.5 inches and 79 inches long. If more than one ridge cap is needed, they must be installed with a 7 inch overlap. The overlap must be over a corrugation so that the overlap is fastened with a nail through the corrugation.
