I. Construction Structure Diagram

Roof Tiles → Wooden Batten Strips → Corrugated Asphalt Waterproof Board → Cement Mortar Leveling → Concrete Roof Base

II. Construction Procedures & Detailed Requirements

1. Pre-Construction Inspection

Before installing corrugated asphalt waterproof board, inspect the flatness and strength of the roof base.

Flatness requirement: Level the roof from ridge to eave in a straight line; the error must be within ±5mm when checked with a 2m straightedge.

2. Waterproof Pre-Treatment

Eave Area:
Lay 3mm self-adhesive modified asphalt waterproof membrane, extending from eave to ridge not less than 500mm.

Inclined Gutter Area:
Use 3mm self-adhesive modified asphalt waterproof membrane for additional treatment, extending at least 250mm to both sides from gutter center. Fixing nails must be at least 260mm upward from gutter center line to avoid penetrating the membrane.

3. Laying Insulation Boards

Lay insulation boards over large areas by mortar spot bonding. On low-slope roofs, insulation boards can be laid directly without additional treatment.

At internal gutters, adjust insulation board thickness to match tile radian. Waterproof board must cover internal gutter tile edge by 2cm toward center line to prevent water backflow.

4. Large-Area Installation of Corrugated Asphalt Waterproof Board

Start laying from eave to ridge, from bottom to top. Overlap upper and lower boards by 100mm, left and right by one wave. Stagger vertical joints by 1/3 or 1/2 sheet width.

Batten Strips: Use preservative pine battens 20×40mm, uniform thickness, few knots.

Fixing: Use expansion nails to penetrate battens, waterproof board and insulation boards, extending into roof structure at least 40mm. Nails must be fixed at wave crests.

5. Key Node Treatment

• Ridge: Seal with 3mm self-adhesive membrane, overlapping waterproof board not less than 250mm on each side.
• Wall Flashing: Overlap waterproof board not less than 250mm, adhere to wall not less than 250mm.
• Dormer: Same as vertical wall flashing; top membrane overlaps 250mm under waterproof board.
• Chimney: Use 500mm wide membrane, wrap corners 150mm for sealing.
• Inclined Ridge: Seal with 500mm wide membrane, 250mm overlap on each side.

6. Batten Strips Installation

Size: 20×40mm, fixed with expansion nails, 10–12 nails per m².

Battens must be straight, firm, joints staggered. Install double battens at eave.

7. Gutter Installation

Construct gutters after main roof tiles installation. Width depends on catchment area and rainfall.

Lay gutter tiles with cement mortar, keep straight and stable.

III. Quality Standards

• Battens: evenly spaced, flat and firm
• Tiles: flat, neatly arranged, tight overlap
• Ridge: correct lap, even spacing, tight seal
• Flashing: meets design, straight, no leakage

IV. Finished Product Protection

Walk only on batten strips or use wooden supports on waterproof board.

Avoid stepping on finished tiles. Cut tiles under roof to prevent dust contamination.

V. Common Quality Issues

• Roof base flatness error → causes tile warping and leakage
• Insufficient overlap length → leads to water leakage
• Incorrect node construction → main cause of roof leakage
• Unqualified structural, waterproof or insulation layers → results in long-term leakage

VI. Safety & Maintenance

Contractor shall install and maintain safety protection at eaves. Protective measures can only be removed after full completion.

All construction personnel must follow safety operation procedures to prevent falling accidents.