Deck Requirements and Roof Specifications Guide
This chart outlines the structural deck surface preparation requirements and roof specification requirements that are necessary for the successful application of a Koppers built-up roofing system with aggregate surfacing.
*Deck requirements are numbers and roof specifications requirements are letters. These designations are in sequence of application.
Structural Deck Type Ref. Notes Apply BUR To: Coal Tar Roofing Specification System*
210 220 410/490 420/920
Metal I, XI Deck N/A N/A N/A N/A
Insulation N/A 1,5,C,F N/A 1,5,C,H
Poured Concrete - Deck N/A 1,6,F N/A 1,6,H
Insulation N/A 1,6,C,F N/A 1,6,C,H
Precast Concrete - Deck N/A N/A N/A N/A
Insulation N/A 1,2,6,C,F N/A 1,2,6,C,H
Lt. Wt. Insul. Concrete/Poured Gypsum - Deck 1,3,7,B,E N/A 1,3,B,G N/A
Insulation N/A 1,3,B,C,F N/A 1,3,B,C,H
Wood Plank/Plywood II Deck 1,4,A,B,E N/A 1,4,A,B,G N/A
Insulation N/A 1,4,A,B,C,F N/A 1,4,A,B,C,H
Precast Gypsum - Deck 1,2,7,B,E N/A 1,2,B,G N/A
Insulation N/A 1,2,B,C,F N/A 1,2,B,C,H
Structural Wood Fiber III Deck N/A N/A N/A N/A
Insulation N/A 1,2,B,C,D,F N/A 1,2,B,C,D,H
*Notes below are also a part of the Deck Requirements and Specification Guide.
*Certain insulation types and/or combinations may be required for certain warranties and Koppers Warranted Application on encapsulated systems.

Deck Requirements
  1. Smooth, dry, solid and properly anchored.
  2. Joints and weldplates, where used, must be grouted with cementitious or gypsum grout feathered to provide a smooth gradual transition between adjacent panels. Additionally an 8" (203mm) wide (min.) felt stripping must be centered on joint and set in trowelings of asphaltic cement.
  3. Substrate must vent moisture to the underside. Koppers allows the installation of non-venting (NVS) lightweight insulating concrete fills over non-venting substrates.
  4. Lumber must be 1" (25mm) nominal thickness and plywood a minimum of 1/2" (13mm) thickness.
  5. Metal deck must not be lighter than 22 gauge (0.7mm) and have the first layer of board type insulation mechanically attached prior to the Koppers Roofing System.
  6. Prime deck with suitable primer when adequate adhesion cannot be obtained. Concrete decks to receive hot asphalt must be primed with asphaltic High-Pen Primer 452.
  7. Any existing roof being considered for a retro-fit (overlay) must first be moisture-surveyed to determine if it qualifies for acceptance and wind uplift requirements.
Roof Specifications
  1. Install 1 layer of red rosin sheathing paper end and side lapped 2"(51mm) and secured to the wood deck by occasional nailing.
  2. Apply over entire surface 1 ply of Koppers non-perforated coated base sheet lapping each sheet 3" (76mm) over preceding sheet and nailing at lap no less than 9" (229mm) o.c. and stagger nailed down center of each sheet on 9" (229mm) centers. End laps shall be 6" (152mm) (approx. 100 nails/per 100 sq.ft. (9.3m2)). Nail heads and/or metal caps must be a minimum diameter of one inch (25mm).
  3. Install approved roof insulation in a solid mopping of steep asphalt or with FM approved mechanical fasteners. Foam type insulations require an overlay board insulation. See Insulation. For metal decks the first layer of insulation must be mechanically attached and a second insulation layer mopped in steep asphalt.
  4. First ply of system must be a Koppers non-perforated coated base sheet set in a solid mopping of steep asphalt.
  5. Complete the system in accordance with Specification No. 210.
  6. Complete the system in accordance with Specification No. 220.
  7. Complete the system in accordance with Specification No. 410 or No. 910.
  8. Complete the system in accordance with Specification No. 420 or No. 920.
Reference Notes:
  1. For acoustical metal decks, an underlayment of asphalt saturated organic felt (ASTM D 226) or a red rosin sheathing paper must be applied with 2" (51mm) end and side laps. A layer of insulation must then be mechanically attached to the deck. Additionally for coal tar specifications, the first ply of the BUR system shall be a non-perforated base sheet embedded in steep asphalt. This is intended to reduce the potential of bitumen drippage.
  2. When roof insulation is specified to be mechanically fastened to a wood deck the base sheet may be eliminated from beneath the insulation. However, the red rosin sheathing paper is required as an underlayment beneath the insulation.
  3. For structural wood fiber decks, when two layers of insulation are used and the top layer has staggered joints and is embedded in steep asphalt, a base sheet is not required as the first ply of the roofing membrane specification. However, a non-perforated base sheet is still required beneath the insulation as specified in the above guide.
  4. For specific data on Insulations, see Roof Insulation.
  5. Vapor retarders are not part of these built-up roofing specifications. For specific information on the acceptable types and application procedures contact your Koppers Representative at 1-800-468-9629.
  6. For Thermosetting Asphaltic Fills, contact your Koppers Representative at 1-800-468-9629.
  7. One square equals 100 sq. ft. (9.3m2) of area.
  8. N/A means Not Applicable.
  9. Dimensions noted in this section are approximate.
  10. For information on Underwriters Laboratories, Factory Mutual or Code Compliance contact Koppers Commercial Roofing Department at 1-800-468-9629.
  11. When only one (1) layer of roof insulation is specified on a metal deck, Koppers requires the insulation be mechanically fastened and the first ply of the built-up roofing system be a base sheet solidly adhered in steep asphalt. Koppers recommends that 2 layers of insulation always be specified for use over metal decks.
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