Under Slab

Stego Vapour Barrier

The most specified and used Vapour Barrier in the United States of America now available in New Zealand.

Stego Wrap Vapour Barrier is made with our proven trade secret blend of prime virgin resins and additives. Stego Wrap Vapour Barrier is an ASTM E 1745 Class A Vapour Barrier.

The Stego Advantage


Against Floor Failures: Experts say “the need for a vapour barrier (as opposed to a vapour retarder) is becoming increasingly clear.”  Concrete Construction Magazine, August 2003, p.18. Infiltration of moisture through concrete slabs is a major building defect liability. Stego Wrap Vapour Barrier has an extremely low permeance preventing water vapour, soil gases (i.e. Radon), alkaline salts and soil sulfates from compromising the integrity of the building envelope and leading to serious problems with the concrete slab, floor coverings and indoor air quality.  Stego Wrap Vapour Barrier is the best protection against these costly failures.



Mould needs three things to survive: moisture, sustained temperature (between 10° and 50° C), and a food source (dust, drywall, etc.).  In any given building environment, contractors can only control one of these variables: moisture.  Mould spores are present in 100% of building interiors. If moisture is allowed into your building environment, mould can and will grow. Toxic moulds like Stachybotyrus can be fatal for nearly 5% of people (Institute of Medicine 1993), and cause a variety of serious health problems in others.  Several recent well-publicised cases involving toxic mould have resulted in multimillion-dollar insurance settlements.  Many of the nation's leading Insurance companies have severely limited or removed coverage for mould claims fearing that these claims will bankrupt their companies.  Now more than ever, it is critically important that extra attention be paid to preventing the intrusion of moisture vapour from your below-slab environment. Stego Wrap Vapour Barrier offers the level of protection that many architects are now seeking and is considered to be inexpensive insurance against these costly failures.

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Stego Wrap Vapour Barrier is NOT made with recycled materials and will not degrade.  Prime, virgin resins are the key. Molecules within Stego Wrap "interlock" to provide strength, durability and unprecedented resistance to moisture vapour and radon gas. Stego Wrap’s puncture resistance is excellent. Stego Wrap will not tear, crack, flake, snag or puncture, even when 18,000 lb. laser-screed machines are driving directly across the barrier.

 IMG 6817



PropertiesTest Method

ASTM E 1745

Class A Requirements

Test ResultExplaination
Permeance ASTM F 1249 0.1 perms 0.0084 perms  * 0.0035 WVTR Very impermeable to water vapour
Punction Resistance ASTM D 1709 2200 grams Method B 2326 grams Resistant to puncturing from construction abuse
Tensile Strength ASTM D 882 45.0 lbf./in. 70.6 lbf./in. Will not tear easily
Permeance after conditioning ASTM E 154 Section 8 0.1 perms 0.0091 perms Permeance after wetting, drying, and soaking
  ASTM E 154 Section 11  0.1 perms 0.0092 perms Permeance after heat conditioning
  ASTM E 154 Section 12  0.1 perms 0.0089 perms Permeance after low temperature conditioning
  ASTM E 154 Section 13  0.1 perms 0.0092 perms Permeance after soil organism exposure
Methane Transmission Rate ASTM D 1434     Greatly impedes the transmission of methane gas
Radon Diffusion Coefficient     1.3 x 10-13m2/second Greatly impedes the transmission of radon gas
Thickness     15 mils Stronger, tougher, and less permeable than much thicker membranes
Roll Dimensions     14 ft. X 140 ft. 1,960 ft2/roll - allows for a minimum of seams
Roll Weight     140lbs. easy to unroll and install


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  • Countdown - Manurewa, St John, Buretta Park, Orewa, Hobsonville, Spitfire Centre Christchurch, Hamilton East, Rotorua, Dinsdale Hamilton
  • The Warehouse - Rolleston
  • The Power Store - Christchurch
  • Foodstuffs - Christchurch
  • Wiri Prison - Auckland
  • Ferrymead Pub - Christchurch
  • KMart - Nelson
  • New World - Kumeu, Whangapararoa, Papakura
  • Caxton Press  Wigram - Christchurch
  • St John Parish - Auckland
  • Westgate Mall - Auckland
  • Chem Waste - Auckland
  • Christchurch Poly VE Block - Christchurch
  • Lyttelton Port - Christchurch
  • Monte Cecilia School - Auckland
  • Village Exchange Hotel - Hastings
  • Marshlands School - Christchurch
  • New Lynn Mall - Auckland
  • University of Canterbury - Christchurch
  • LDS Church - Ashburton
  • Paremoremo Prison - Auckland
  • Crombie and Price - Oamaru
  • Pak 'n' Save - Tauranga
  • Britomart Transport - Auckland
  • Porter Fleet - Hamilton
  • Countdown - Ashburton
  • Wainoni Fire Station - Christchurch
  • Woodend School - Christchurch
  • Briscoes - Petone
  • On Gas Filling Plant - Auckland
  • Park Hyatt - Auckland
  • Mrs Higgins Pie Factory - Auckland
  • Canterbury University Engineering Lab - Christchurch
  • Lifestyle Beverages Factory - Hastings
  • Marsden Boat Facility - Ruakaka
PRODUCT 0.38mm Thick, 4.3m Wide x 42.7m Long with 150mm Lap 0.25mm Thick, 4.3m Wide x 64m Long
CANZAC CODE 21 515 21 510
UNIT 183.6m2/Roll 275.2m2


PRODUCT Stego Tape Crete Claw Tape Termination Bar Stego Mastic
CANZAC CODE 21 500 21 535 21 530 21 520
UNIT 55M / Roll 55M / Roll 1.2M Length 19L Pail


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Ask a Question about Stego Barrier



Stego Wrap is our line of high-performance, below-slab vapour retarders/barriers. Our products help protect the building envelope from below-slab moisture vapour, soil gases, and other contaminants.

What is so great about Stego Wrap?

Stego Wrap Vapour Barrier is specifically engineered to provide extremely low permeance, longevity, and durability. Our trade secret blend of prime virgin resins and additives combined with state-of-the-art manufacturing processes make the performance and consistency of Stego Wrap Vapour Barrier second to none.


In order of importance:

  1. low permeability
  2. longevity (does not decompose)
  3. puncture resistance
  4. installation efficiency
  5. price
What is ASTM E 1745?

The industry standard for plastic vapour retarders used under concrete slabs.

ASTM E 1745 "Standard Specification for Plastic Water Vapour Retarders Used in Contact with Soil or Granular Fill under Concrete Slabs." is the main standard for evaluating plastic films that will be used in this application.Three performance classes are outlined A, B and C (with Class A being the strongest). Permeance levels are the same for each class. Tensile Strength and Puncture Resistance change with each class.

ASTM E 1745 refers to ASTM E 154 "Standard Test Methods for Water Vapour Retarders Used in Contact with Earth Under Concrete Slabs, On Walls or as Ground Cover." which describes test methods for testing the performance of a plastic film after it is subjected to certain elements.