Product Data Sheet Show all documents

Sarnafil® AT-18

1.8-mm-thick polymeric FPO membrane for mechanically fastened and ballasted roof waterproofing

Sarnafil® AT-18 (thickness 1.8 mm) is a premium multi-layer synthetic roof waterproofing sheet based on elastomer modified flexible polyolefin (FPO) with internal Polyester reinforcement and glass non-woven inlay and a Polypropylene backing according to EN 13956. The product is hot air weldable, UV-stabilised with extrenal fire performance. Can be applied in all climatic zones.

  • Highly flexible membrane allows for easy application
  • High durability and long service life
  • IMPORTANT Requires named reference to an established recycling programme for post-consumer FPO that is easily accessible for > 65 % of customers and that feeds post-consumer recycling material to production of new products. Delete if no such recycling programme is available. Can be recycled after service life through [named] recycling program
  • Hot-air welding application avoids fire risk
  • White coloured membranes reduce air conditioning costs by reducing heat transmission into the building
  • Dimensionally stable membrane reduces wrinkling and increases ease of application
  • Increased resistance to damage through wind uplift
  • UV-stabilised product with increased service life in areas with high UV-exposure
  • Increased resistance to root penetration
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Product Data Sheet Show all documents

Usage

Sarnafil® AT-18 is used as a waterproofing membrane in the following roofing applications:
  • Mechanically fastened roofing systems
  • Ballasted roofing systems

Advantages

  • Highly flexible membrane allows for easy application
  • High durability and long service life
  • IMPORTANT Requires named reference to an established recycling programme for post-consumer FPO that is easily accessible for > 65 % of customers and that feeds post-consumer recycling material to production of new products. Delete if no such recycling programme is available. Can be recycled after service life through [named] recycling program
  • Hot-air welding application avoids fire risk
  • White coloured membranes reduce air conditioning costs by reducing heat transmission into the building
  • Dimensionally stable membrane reduces wrinkling and increases ease of application
  • Increased resistance to damage through wind uplift
  • UV-stabilised product with increased service life in areas with high UV-exposure
  • Increased resistance to root penetration

Packaging

Standard rolls are wrapped individually in a blue PE-foil.

Roll width

2 m

Roll length

15 m

Roll weight

60 kg

Refer to the current price list for available packaging variations.

Colour

Top layer colour

beige, window grey (~RAL 7040), basalt grey (~RAL 7012), traffic white (~RAL 9016)

Bottom layer colour

dark grey

Product Details

Sustainability / Certifications / Approvals

ENVIRONMENTAL INFORMATION

  • Specific Environmental Product Declaration (EPD) in accordance with EN 15804. EPD independently verified by Institut für Bauen und Umwelt e.V. (IBU)

  • Contributes towards satisfying Materials and Resources (MR) Credit: Building product disclosure and optimization — Environmental Product Declarations under LEED® v4

  • Contributes towards satisfying Materials and Resources (MR) Credit: Building Product Disclosure and Optimization — Material Ingredients under LEED® v4

  • Contributes towards satisfying Materials and Resources (MR) Credit: Building Product Disclosure and Optimization — Sourcing of Raw Materials under LEED® v4

  • Contributes towards satisfying Sustainable Sites (SS) Credit: Heat Island Reduction under LEED® v4

  • Work hygiene-related aspects of welding Sarnafil® AT (FPO-based)

APPROVALS / STANDARDS

  • CE marking and declaration of performance based on EN 13956:2012 Flexible sheets for waterproofing — Plastic and rubber sheets for roof waterproofing — Definitions and characteristics

  • Cradle Certified® Silver, Sarnafil® AT and SikaRoof® AT, Cradle, Certificate No. 5933

  • Cradle to cradle Certificate Silver STANDARD3.1, Sarnafil® AT and SikaRoof® AT

  • Determination of resistance DIN EN 13956, Sarnafil® AT-15, UAS Weihenstephan-Triesdorf,

  • Sheets for roof waterproofing DIN CEN/TS 16637-2, Sarnafil® AT, OST

  • Certificate of Compliance, Sarnafil® AT, FM Approvals, Certificate No. PR464094

  • Fire performance classification to Brooft4 EN13501-5 (subject to construction)
Product Information

Chemical Base

Flexible polyolefins (FPO)

Shelf Life

5 years from date of production.

Storage Conditions

The Product must be stored in original unopened and undamaged sealed packaging in dry conditions and temperatures between -5 °C and +40 °C. Store in a horizontal position. Do not stack pallets of the rolls on top of each other, or under pallets of any other materials during transport or storage. Always refer to the packaging.

Product Declaration

EN 13956 - Polymeric sheets for roof waterproofing

Visible Defects

Pass

(EN 1850-2)

Length

15 m (+0.75 m / -0 m)

(EN 1848-2)

Width

2 m (+0.02 m / -0.01 m)

(EN 1848-1)

Effective Thickness

1.8 mm (+0.18 mm / -0.09 mm)

(EN 1849-2)

Straightness

≤ 30 mm

(EN 1848-2)

Flatness

≤ 10 mm

(EN 1848-2)

Mass per unit area

2.0 kg/m² (+0.2 kg/m² / -0.1 kg/m²)

(EN 1849-2)
System information

Compatibility

Discolouration of the membrane surface may occur if it is in direct contact with bitumen. To prevent discolouration, use separation layer.

Technical Information

Resistance to Impact

Method A, Hard support

≥ 1250 mm

Method B, Soft support

≥ 2500 mm

Hail Resistance

Hard support

≥ 27 m/s

Soft support

≥ 38 m/s

Resistance to Static Load

Hard support

≥ 20 kg

Soft support

≥ 20 kg

Resistance to Root Penetration

Pass

(EN 13948)

Dimensional Stability

Longitudinal (MD), aged 6 hours at +80 °C

≤ |0.4| %

Transversal (CMD), aged 6 hours at +80 °C

≤ |0.2| %

Resistance to Tearing (nail shank)

Longitudinal (MD)

≥ 300 N

Transversal (CMD)

≥ 300 N

Joint Peel Resistance

Failure mode C. No failure of the joint

(EN 12316-1)

Joint Shear Resistance

≥ 400 N/50 mm

(EN 12317-2)

Foldability at Low Temperature

≤ -50 °C

(EN 495-5)

External Fire Performance

B Roof T4, roof angle < 10° (subject to construction)

Pass

Reaction to Fire

Class E

(EN 13501-1)

Chemical Resistance

Resistant to specific chemicals.

Contact Sika Technical Services for additional information.

(EN 1847)

Exposure to Bitumen

Bitumen compatibility

Pass

UV Exposure

> 5000 hours UV exposure

Grade 0

Artificial Ageing

Pass ( > 5000 h, grade 0)

(EN 1297)

Diffusion Resistance to Water Vapour

Resistance factor, Method A, tested at +23 °C and 75 % r.h.

μ = 190 000

Water Tightness

Method B: at 10 kPa

Pass

Application

Application Information

Ambient Air Temperature

Maximum

+60 °C

Minimum

-20 °C

Substrate Temperature

Maximum

+60 °C

Minimum

-25 °C
Application steps

EQUIPMENT

HOT-WELDING OVERLAP SEAMS

  • Electric hot-air welding equipment such as hand-held, manual hot-air welding equipment and pressure rollers

  • Automatic hot-air welding machines with controlled hot-air temperature capability of a minimum +600 °C

Recommended equipment:

Manual

Leister Triac

Automatic

Varimat

SUBSTRATE PREPARATION

The substrate surface must be smooth and uniform.

The supporting layer must be compatible with the membrane, resistant to solvents and dry.

  1. Remove any sharp protrusions or burrs from the substrate.
  2. If contaminants such as grease or dust are present, clean the supporting layer.

APPLICATION

IMPORTANT

Strictly follow installation procedures

Strictly follow installation procedures as defined in Method Statements, application manuals and working instructions which must always be adjusted to the actual site conditions.

IMPORTANT

Application by trained personnel

The application of this Product must only be carried out by an applicator that is trained or approved by Sika. The applicator must also be experienced in this type of application.

FIXING METHOD - GENERAL

The waterproofing membrane is installed by loose laying – without stretching the membrane or installing under tension – with mechanical fastening in the seam overlaps or independently of overlaps. Overlap seams are hot-air welded using specialised hot-air equipment.

FIXING METHOD - SPOT FASTENING (SARNAFAST®)

  1. Install the Product at right angles to the deck direction. Unroll the waterproofing membrane, overlapping it by 120 mm.
  2. Fix the waterproofing membrane using Sarnafast® fasteners, barbed washers and tubes along the marked line, 35 mm from the edge of the membrane. The spacing of the fasteners must be in accordance with the project specific Sika calculations.
  3. At upstands and at all penetrations, secure the Product with a Sarnabar®.
  4. Use the 4 mm diameter Sarnafil® T Welding Cord to protect the roof covering against tearing and peeling off by wind uplift.

 

FIXING METHOD - FIELD FASTENING

  1. Install the membrane at right angles to the deck direction. Unroll the waterproofing membrane, overlaping it by 80 mm.
  2. Fix the membrane by induction-welding Sarnadisc hot melt coated washers and Sarnafast® fasteners along the marked line, 35 mm from the edge of the membrane. The spacing of the fasteners must be in accordance with the project specific Sika calculations.
  3. At upstands and at all penetrations, secure the Product with a Sarnabar®.
  4. Use the 4 mm diameter Sarnafil® T Welding Cord to protect the roof covering against tearing and peeling off by wind uplift.

FIXING METHOD - BALLASTED SYSTEM

  1. Unroll the waterproofing membrane, overlapping it by 80 mm.
  2. Immediately weld the overlap seams.
  3. Cover with the appropriate roof material according to the roof design and the local wind loading conditions.
  4. Mechanically fix around the roof perimeter with Sarnabar® including Sarnafil® T Welding Cord to keep the membrane in place.

HOT-WELDING OVERLAP SEAMS

Overlap seams must be welded by electric hot-welding equipment. Prior to welding, welding parameters including temperature, machine speed, air flow, pressure, and machine settings must be evaluated, adapted and checked on site according to the type of equipment and the climatic conditions. The effective width of overlaps welded by hot air must be a minimum of 20 mm.

TESTING OVERLAP SEAMS

  1. Mechanically test seams with a rounded-edge screwdriver to ensure the integrity and completion of the weld.
  2. Rectify any imperfections using hot-air welding.

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