Conductive mesh for roofing and waterproofing leak detection

Published by Atlantic Testing Services · conductivemediums.com
Edit freely for project use.

PART 1 — GENERAL

1.1 Summary

1. This Section includes conductive stainless steel mesh installed within roofing or waterproofing assemblies to provide an electrical reference for Electronic Leak Detection (ELD).
2. Work of this Section includes:
   1. Furnishing conductive mesh.
   2. Installing mesh over insulation or approved substrate.
   3. Providing overlaps and electrical continuity between adjacent mesh runs.
   4. Connecting mesh to grounded building elements where required.
   5. Furnishing and installing connection plate assemblies for test equipment access.
   6. Coordinating installation with insulation, cover board, membrane, and leak detection system requirements.
3. Conductive mesh is intended for use where:
   1. No other suitable electrical reference is available for high-voltage or low-voltage manual leak detection methods; or
   2. The assembly is being constructed to allow installation or retrofit of a permanent leak detection monitoring system at a later date.

1.2 Related Sections

1. Section 07 22 00 — Roof and Deck Insulation
2. Section 07 50 00 — Membrane Roofing
3. Section 07 55 00 — Protected Membrane Roofing
4. Section 07 56 00 — Fluid-Applied Roofing
5. Section 07 60 00 — Flashing and Sheet Metal
6. Section 07 90 00 — Joint Protection
7. Section 07 91 00 — Leak Detection Systems
8. Division 26 — Electrical: grounding and bonding, where required

1.3 References

1. ASTM A313 — Standard Specification for Stainless Steel Spring Wire
2. ASTM B557 — Standard Test Methods for Tension Testing Wrought and Cast Aluminum- and Magnesium-Alloy Products
3. ASTM D7877 — Standard Guide for Electronic Methods for Detecting and Locating Leaks in Waterproof Membranes
4. ASTM D8231 — Standard Practice for the Use of a Low Voltage Electronic Scanning System for Detecting and Locating Breaches in Roofing and Waterproofing Membranes

1.4 Coordination

1. Coordinate placement of conductive mesh with installation of insulation, cover board, membrane roofing, waterproofing, flashings, drains, penetrations, and leak detection components.
2. Do not install conductive mesh directly below the roofing or waterproofing membrane unless specifically approved by both the membrane manufacturer and the leak detection system provider.
3. Coordinate electrical continuity requirements with the leak detection system provider before installation.
4. Where mesh is to be connected to grounded structure, coordinate connection locations with the Architect, membrane manufacturer, leak detection provider, and electrical grounding requirements.
5. Coordinate location of connection plate assemblies with the leak detection provider so that test access is available without disturbing the completed assembly.

1.5 Submittals

1. Product Data: Submit manufacturer's product data for conductive mesh, including material, roll dimensions, mesh opening size, wire diameter, tensile strength, elongation, and intended use.
2. Installation Instructions: Submit manufacturer's written installation instructions.
3. Shop Drawings: Submit layout drawings showing:
   1. Mesh roll layout and direction of runs.
   2. Side and end lap locations.
   3. Terminations.
   4. Transitions at penetrations, drains, curbs, parapets, and changes in plane.
   5. Grounding or bonding connection locations, where required.
   6. Connection plate assembly locations.
   7. Coordination with leak detection system components.
4. Closeout Submittals:
   1. Record drawings showing installed mesh layout, connection plate locations, and grounding connection locations.
   2. Manufacturer's product data and installation instructions.
   3. Electrical continuity verification reports, where required by project documents.

1.6 Quality Assurance

1. Installer Qualifications: Installer shall be experienced in roofing or waterproofing assemblies and familiar with installation of conductive reference layers for leak detection systems.
2. Preinstallation Conference: Conduct a preinstallation conference before installing conductive mesh. Review:
   1. Substrate readiness.
   2. Mesh layout and sequencing.
   3. Required overlaps and continuity.
   4. Cutting and handling procedures.
   5. Grounding connection requirements.
   6. Connection plate assembly installation and sequencing.
   7. Coordination with cover board installation.
   8. Coordination with membrane installation.
   9. Leak detection testing procedures.
3. Mockup: Where required by the Architect, install a representative mockup demonstrating mesh placement, overlaps, taping, grounding connection, connection plate assembly, and cover board installation.

1.7 Delivery, Storage, and Handling

1. Deliver materials in original packaging with labels intact.
2. Store materials dry, off the ground, and protected from damage.
3. Handle rolls to avoid deformation, contamination, or loss of mesh continuity.
4. Cut and loose wire ends are sharp. Workers shall wear gloves and eye protection when handling, cutting, or installing mesh.

1.8 Field Conditions

1. Install conductive mesh only when substrate conditions are suitable for the roofing or waterproofing assembly.
2. Do not install mesh over wet, contaminated, or unstable substrates.
3. Protect installed mesh from displacement or damage before cover board installation.

PART 2 — PRODUCTS

2.1 Manufacturer

1. Basis-of-Design Product: ConDuct™ Stainless Steel Mesh — Open-net Style, supplied by Atlantic Testing Services, conductivemediums.com, 888-696-6429, service@atlanticleak.com.
2. Substitutions: Submit in accordance with Division 01. Substitute products shall demonstrate equivalent material, conductivity, durability, corrosion resistance, dimensional characteristics, and compatibility with the roofing or waterproofing assembly and the leak detection system.

2.2 Conductive Mesh

2.3 Connection Plate Assembly

1. Provide a connection plate assembly at each monitored area to permit connection of leak detection test equipment above the finished membrane without disturbing the assembly.
2. Assembly shall include:
   1. PVC base for mechanical attachment to the roof deck.
   2. Connection plate with attached lead wire.
   3. Redundant lead wire, separately coiled.
   4. Weatherproof electrical enclosure with cover.
3. Materials required but not furnished with the assembly: 3/4 inch PVC electrical conduit, PVC conduit solvent cement, deck fasteners appropriate to the deck material, and aluminium foil tape.

2.4 Accessory Materials

1. Tape for Temporary Positioning:
   1. Duct tape or aluminium tape, acceptable for holding adjacent mesh runs in position before cover board installation.
   2. Tape shall not interfere with mesh continuity or with performance of the roofing or waterproofing assembly.
2. Grounding or Connection Material, Where Required:
   1. Stainless steel wire, or a 2 inch wide strip of conductive mesh or grounding screen.
   2. Clamps, fasteners, screws, or other secure connection methods suitable for the building element being connected.
   3. Materials shall be compatible with stainless steel mesh and with the grounded building element.
3. Low-Rise Foam Adhesive: As specified by the roofing or insulation manufacturer for cover board installation.

PART 3 — EXECUTION

3.1 Examination

1. Examine substrates before installation of conductive mesh.
2. Verify that insulation or other substrate is properly installed, clean, dry, stable, and ready to receive mesh.
3. Verify that required penetrations, drains, curbs, and other elements affecting mesh layout are installed or coordinated.
4. Do not begin installation until unsatisfactory conditions have been corrected.

3.2 Preparation

1. Review approved layout drawings before installation.
2. Confirm whether the mesh is to function as:
   1. Sole electrical reference for the leak detection system; or
   2. Conductive layer bonded to the grounded structure of the building.
3. Confirm required grounding or bonding points before placing mesh.
4. Confirm connection plate assembly locations before placing mesh.
5. Provide gloves and eye protection for personnel handling and cutting mesh.

3.3 Cutting

1. Cut mesh using a small circular grinding wheel or other manufacturer-recommended cutting tool.
2. Standard metal cutting shears may be used only where acceptable to the installer and manufacturer; the mesh is tough and will dull standard shears quickly.
3. Follow standard safety procedures when using grinders or other cutting tools.
4. Remove or secure sharp wire ends that could damage adjacent materials or create hazards.

3.4 Connection Plate Assembly Installation

1. Fasten the PVC base directly to the roof deck using fasteners appropriate to the deck material.
2. Cut PVC conduit of sufficient length to extend from the roof deck to not less than 18 inches above the finished membrane. Solvent-cement the conduit into the base.
3. Solvent-cement the weatherproof enclosure to the top of the conduit.
4. Install the roof assembly around the base and conduit, stopping at the top of the insulation. Do not install cover board or membrane until mesh and connections are complete.
5. Drill two 1/4 inch holes on opposite sides of the conduit, level with the top of the insulation.
6. Route the connection plate lead wire and the redundant lead wire, one through each hole, up the interior of the conduit to the enclosure. Coil surplus wire within the enclosure and install the weatherproof cover.
7. Install mesh so that it lies directly over the connection plate.
8. Strip 6 inches of insulation from the end of the redundant lead wire and weave the bare conductor into the mesh.
9. Secure the bare conductor and the connection plate with aluminium foil tape.
10. Flash the conduit penetration in accordance with the membrane manufacturer's requirements.

3.5 Installation — General

1. Install conductive mesh between the insulation and the cover board unless otherwise approved by the manufacturer and the leak detection provider.
2. Do not install mesh directly below the roofing or waterproofing membrane.
3. Unroll mesh over insulation or approved substrate.
4. Install mesh flat, without excessive wrinkles, folds, buckling, or displacement.
5. Overlap adjacent mesh runs a minimum of 2 inches at side laps and end laps.
6. Maintain positive contact between adjacent mesh runs at all side and end laps.
7. Tape adjacent mesh runs together using duct tape or aluminium tape spaced approximately 5 to 10 feet on center, or as required to prevent displacement before cover board installation.
8. Maintain mesh continuity across the entire area intended to be monitored.
9. Coordinate installation at drains, penetrations, curbs, walls, and changes in plane to maintain continuity and avoid damage to adjacent components.

3.6 Installation — Mesh as Sole Electrical Reference

1. Roll out mesh over the insulation or approved substrate.
2. Install mesh in accordance with Article 3.5.
3. Install cover board over mesh in accordance with the roofing or insulation manufacturer's instructions.
4. Where cover board is adhered with low-rise foam, apply foam directly onto the conductive mesh in accordance with the manufacturer's procedure.

3.7 Installation — Mesh Bonded to Grounded Structure

1. Roll out mesh over the insulation or approved substrate.
2. Install mesh in accordance with Article 3.5.
3. Connect mesh to conductive building elements at several separate locations where possible.
4. Acceptable conductive building elements may include:
   1. Metal deck
   2. Metal curb
   3. Metal vent stack
   4. Metal drain body
   5. Other grounded conductive elements approved by the Architect and leak detection provider
5. Use a 2 inch wide strip of grounding screen, a strip of conductive mesh, or stainless steel wire extending from the body of the mesh to the grounded element.
6. Securely tape, clamp, screw, or otherwise fasten the strip or wire to the grounded building element.
7. Install cover board over mesh in accordance with the roofing or insulation manufacturer's instructions.
8. Where cover board is adhered with low-rise foam, apply foam directly onto the conductive mesh in accordance with the manufacturer's procedure.

3.8 Field Quality Control

1. Inspect installed mesh before cover board placement for:
   1. Correct location within the assembly.
   2. Minimum 2 inch overlaps at all laps.
   3. Positive contact at laps.
   4. Continuity at side and end laps.
   5. Secure temporary taping.
   6. Correct grounding connections, where required.
   7. Correct connection plate assembly installation and mesh-to-plate contact.
   8. Absence of displacement, damage, or sharp projections that could affect adjacent materials.
2. Verify electrical continuity of the installed mesh where required by the leak detection system provider.
3. Correct discontinuities, inadequate overlaps, loose areas, or damaged mesh before installing cover board.
4. Do not cover mesh until required inspections and verifications are complete.

3.9 Protection

1. Protect installed mesh from displacement, damage, contamination, and construction traffic.
2. Do not drag materials or equipment over exposed mesh.
3. Repair or replace damaged mesh before cover board installation.
4. Proceed with cover board installation promptly after mesh placement to reduce risk of displacement or damage.

3.10 Closeout

1. Provide record documentation showing installed mesh layout, connection plate locations, and grounding connection locations.
2. Provide continuity verification documentation where required.
3. Submit product data and installation instructions as closeout records.

END OF SECTION

Prepared by Atlantic Testing Services. This specification is provided as an editing aid for design professionals and may be modified for project use. Verify all requirements against project conditions, applicable codes, and the requirements of the membrane manufacturer and leak detection system provider.

Materials available at conductivemediums.com · 888-696-6429 · service@atlanticleak.com