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D3019 – Standard Test Method Technical Guide
🏗️ Classification and Types of Lap Cement
The standard, designated D3019/D3019M-17 (2024), covers lap cement for use with asphalt roll roofing. Two types are defined:
Type I is a brushing consistency, non-fibered cement intended for exposed-nailing methods. It contains no mineral or other stabilizers and is further classified into Grade 1 (air-blown asphalt) and Grade 2 (vacuum-reduced or steam-refined asphalt).
Type III is a heavy brushing or light troweling consistency, fibered cement used in concealed-nailing methods. It includes mineral or other stabilizers but is free from asbestos fibers.
| 🟦 Type | 📏 Grade | 📐 Consistency | 🎯 Asphalt Type | ⚡ Additives |
|---|---|---|---|---|
| Type I | Grade 1 | Brushing | Air-blown asphalt | None |
| Type I | Grade 2 | Brushing | Vacuum-reduced or steam-refined asphalt | None |
| Type III | — | Heavy brushing or light troweling | As required per specification | Mineral/stabilizers, no asbestos |
🔬 Physical Requirements and Test Methods
Per Section 4, all lap cement types must conform to the physical requirements detailed in Table 1 of the standard. Testing is performed according to Test Methods D6511/D6511M for solvent-bearing bituminous compounds and Test Method D36/D36M for softening point determination using the ring-and-ball apparatus.
The softening point and composition are key parameters ensuring proper performance in roofing applications. For Type III cements, additional attention is given to lap strength under Section 6.2.
| 🟦 Property | 📏 Test Method | 🎯 Application |
|---|---|---|
| Softening Point | D36/D36M | All types and grades |
| Composition | D6511/D6511M | All types |
| Lap Strength | D6511/D6511M (per Section 6) | Type III only |
⚙️ Strength of Lap and Inspection
Section 6.2 emphasizes the significance of lap strength for Type III cement in concealed-nailing roll roofing. This test ensures the adhesive bond between overlapping layers can withstand structural loads.
Inspection and rejection procedures are covered in Sections 7 and 8. The purchaser and supplier must agree on inspection terms, and failure to meet specification requirements justifies rejection. The seller retains the right to reinspect rejected materials.
⚠️ Important: The lap strength requirement applies exclusively to Type III cement used in concealed-nailing applications. Type I cement is not subject to this testing under this standard.
💡 Note: Always use the latest revision of referenced test methods. The standard also advises following safety protocols per Section 1.3 when handling solvent-bearing materials.
❓ Frequently Asked Questions
🔍 What is the primary difference between Type I and Type III lap cement?
Type I is non-fibered with brushing consistency for exposed-nailing methods, while Type III is fibered with heavy brushing or light troweling consistency for concealed-nailing methods.
💡 What are the grades for Type I lap cement?
Type I includes Grade 1, made with air-blown asphalt, and Grade 2, made with vacuum-reduced or steam-refined asphalt.
⚡ Why is lap strength important only for Type III cement?
Lap strength is critical for Type III due to its use in concealed-nailing installations where the adhesive bond must resist separation under load. Type I uses exposed nails, so lap bond is less critical.
📌 What test methods are specified in this standard?
Test Methods D6511/D6511M for composition and physical properties, and Test Method D36/D36M for softening point via ring-and-ball apparatus.