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DocuSign Envelope ID: B49FB256 -4ADF- 4759- AF63- 134AD44FC239 <br />5thWall Building Diagnostics Consultants <br />3.04 Underlayment <br />Slate Roof Replacement <br />Orange County Skills Development Center <br />Chapel Hill, NC <br />August 2017 <br />A. Install one ply of self - adhering membrane over the existing deck. Membrane shall be <br />installed perpendicular to the roof slope in shingle fashion in horizontal layers with joints <br />lapped toward eaves. <br />B. Install metal edge flashing after installing membrane underlayment. Flange of metal edge <br />flashing shall be set in full bed of roof flashing cement. Secure edge flashing with nails at 4 <br />inches o.c. <br />C. Underlayment shall lap over valley metal 2 inches. <br />3.05 Slate <br />A. After installation of new underlayment reinstall existing slate. Slate shall project 1 inch at <br />eaves and shall be laid in horizontal courses with 3 inch headlap. <br />B. Each course shall break joints with the preceding one a minimum of 3 inches. Overlapping <br />slate shall be jointed as near the center of the underlying slate as possible and not less than 3 <br />inches from any underlying joint. Vertical surfaces shall be laid with a 1 inch headlap. <br />C. Slates at eaves or cornice line shall be canted 1/4 inch with copper sheet metal as shown on <br />the detail drawings. <br />D. Slate shall be secured to the deck with two nails per piece. Nails shall not be driven in so far <br />as to exert strain on the slate nor shall the nail be underdriven resulting in bridging of the <br />overlying slate; the nail head shall just touch the slate with sufficient clearance to allow the <br />slate to hang on the nail. <br />E. Nails shall not be positioned directly on top of deck joints. <br />F. Exposed nail heads shall not be allowed except where unavoidable in top courses. Cover all <br />exposed nail heads with flashing cement. <br />G. Hip and ridge slates shall be laid in a heavy bed of flashing cement applied over unexposed <br />surface of under courses of slate. Nail slates securely in place and point with flashing <br />cement. <br />H. All hips shall be laid to form "saddle" hips with metal underneath. Ridges shall be laid to <br />form "saddle" ridges. Nails for the combing of slate shall pass through the joints of slate <br />below. <br />I. Install 20 oz copper flashing as part of hip and ridge construction. <br />Slate shall be neatly fit around pipes, projections, ventilators, etc. <br />K. Slates which overlap sheet metal work shall have nails positioned so as to avoid puncturing <br />the sheet metal. Use copper wire, as needed, to aid in securement of slate. <br />17 -198 Slate Roofing <br />073300.4 <br />