Prep Work Requirements for Clay Tiled Roofs

Prep Work Requirements for Clay Tiled Roofs

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

Clay tile roof batten guidelines: this article describes the requirements for battens on clay tile roofs, and how to stack and lay out tiles for roof installation.

Prep Work Requirements for Clay Tiled Roofs

This article describes the requirements for battens on clay tile roofs, and how to stack and lay out tiles for roof installation. This article series discusses best practices in the selection and installation of residential roofing. This article includes excerpts or adaptations from Best Practices Guide to Residential Construction. by Steven Bliss. courtesy of Wiley & Sons.

Batten Specifications for Clay Tiled Roofs

Tiles with projecting head lugs can be installed either directly on the deck or with the lugs fitting over pressure-treated wooden battens nailed horizontally across the roof.

Roof tile battens are typically nominal 1×2 or 1×4 lumber, but they may be larger to accommodate snow loads or unsupported spans over counterbattens.

[Click to enlarge any image]

Battens for use on clay tile roofs should be made from pressure-treated lumber except in very dry climates.

Clay tile roof battens are nailed at minimum 24 inches on-center with spaces for drainage every 48 inches. Lay out battens to provide equal courses with a minimum 3-inch head-lap, unless the tile profile is designed for a specific head-lap.

Watch out. as Smith (NRCA) pointed out, battens shimmed off of the roof deck should be supported 12 o.c. to avoid sagging. -Ed.

Fasten the roof battens with 8d galvanized nails or corrosion-resistant 1 1/2-inch 16-gauge staples with 7/16-inch crowns.

Battens under clay roofing tiles are recommended on roof slopes greater than 7:12 to provide solid anchoring and on slopes below 3:12 to minimize penetration of the underlayment. On low slopes and in areas subject to ice damming, counterbattens nailed vertically up the roof slope are also recommended to promote drainage.

Counterbattens on clay tiled roofs should be minimum 1/4 x 2 inches thick in moderate climates, 3/4 inch thick in areas subject to ice damming. When battens are nailed directly to the deck, allow a 1/2 -inch gap every 4 feet or set the battens on minimum 1/4 -inch shims placed at each nail (see Figure 2-21 above).

Layout and Stacking Specifications for Tiled Roofs

Prep Work Requirements for Clay Tiled Roofs

Lay out the courses so that tile exposures are equal with a head-lap of at least 3 inches (unless the tile specifies a different lap).

Snap lines on the underlayment along the top of each course or along each batten. One or more vertical lines can also be helpful in keeping the tiles aligned. Accurate layout is critical with most tile patterns.

Next, carry tiles up to the roof and distribute the weight equally across the roof, as tiles weigh as much as 10 pounds each.

Depending on the tile, stacks of about 6 to 10 tiles is workable. Our photos (above-left — DF) shows roof tiles stacked and ready for installation in Mesquite Cove AZ.

If mixing different colored tiles, arrange bundles with the correct proportions on the ground before stacking them on the roof.

Tile Roof Batten Options from NRCA

In the 1990’s NRCA’s Thomas Smith noted that a paper published in the Proceedings of the 10th Conference on Roofing Technology expressed concern for the lack of conservative roofing industry guidelines for the components of tile roofing systems in the U.S. The recommendations in the then-current NRCA Steep Roofing and Waterproofing Manual indeed included recommendations for tile roof underlayment, fasteners, and metal flashings, but Smith noted that these were non-conservative for many areas in the United States (and other locations of challenging weather).

Smith posed some interim batten options to improve the life of tile roof systems, including

    Except in hot and dry areas (U.S. desert Southwest for example) use preservative treated battens (as recommended above by Bliss); Use treated wood for ridge and hop nailers Use treated wood for strips into which tiles are fastened; Wood treatment should comply with AWPA Standards C2 and P5 or AWPB LP-2 Use battens 4 feet long with a space of 1/2 between ends of each batten to provide a drainage path for water that passes through the tiles to the underlayment, or provide kerf cuts about 1/4 wide at 2 on center [presumably on the bottom surface of all battens — Ed.] — or Spacers (shims) can be placed between batten and roof underlayment to hold the batten off of the roof surface using spacers constructed of 2 squares of asphalt shingles or treated wood lath, 12 on center to avoid batten sagging

Leave a Reply