duram duramax
textured coatings waterproofing antislip

Product Data Sheet

Multithane UV

UV Resistant, Polyurethane Waterproofing Membrane


Multithane UV is a single pack, liquid applied, moisture curing, self leveling, waterproofing membrane which cures to form a seamless, tough, durable, elastomeric (class 3 ) waterproofing membrane. 
Multithane UV incorporates UV stabilisers and UV absorbers to enable the product to provide greater UV protection and stability than conventional aromatic polyurethane membranes. 
Multithane UV bonds well to most suitably primed building substrates and is suitable for above and below ground applications.
Mulithane UV is Grey.
Multithane UV is also available in a thicker grade Multithane UV HV (High Viscosity) for exposed vertical surfaces.
Multithane UV meets the 'Green Star' environment criteria.

Important: Although the product incorporates UV stabilisers, UV Absorbers and anti-oxidants to prolong its serviceable life when exposed to sunlight, the product being an aromatic polyurethane will nevertheless slowly degrade. It is therefore highly recommended that the product be over coated with Multithane ATC (aliphatic top coat) which is an aliphatic polyurethane formulated to withstand direct sunlight exposure, resist chalking and colour fading. In combination, the system provides the ultimate in long terms waterproofing membrane technology.


Multithane UV is designed to waterproof most applications within the building and construction industry including: 

Exposed Areas: Roofs, decks, terraces, balconies, podiums and gutters. 

Tiled or Covered Areas: Shower recess & wet areas (floors and upturns), decks, balconies, terraces, podiums, retaining walls, planters & landscaped areas, structural slabs, tanks, pits, bunding areas and water features.

Suitable Surfaces

Multithane UV is suitable for most building substrates including: Concrete • Cement •  Cement Render • FC and CFC Sheeting • Render • Brick • Block work • Plaster Board • Masonry • Bitumen (when primed with Duram Primeseal)  • Metal • Timber, Particle Board and Plywood ( when primed with Duram Primeseal).

Surfaces must be made good and should be sound, stable, dry, clean and free of dirt, dust and contaminants and suitably primed.


The information contained in this product data sheet is typical but does not constitute a full specification as conditions and specific requirements may vary from project to project. The instructions should be considered as a minimum requirement but the applicator or contractor must use their skill, knowledge and experience to carry out additional works as may be necessary to meet the requirements of the project. Specification for specific projects should be sought from the Company in writing.


The product contains protective technology including UV absorbers, UV blockers and anti-oxidants to give the product UV resistance and is therefore suitable for exposed applications. Colour may lighten and the product may chalk after periods of exposure or immersion. However, where extended UV resistance is required, Multithane UV should be top coated with Multithane ATC.

No warranty will apply unless over-coated with Multitrhane ATC. Please refer to the relevant product data sheet.

Benefits and Advantages

Multithane UV represents the highest standards in polyurethane waterproofing technology and provides the following benefits and advantages:
• Single pack - no mixing.
• Fast curing  within 24 hours).
• Meets the 'Green Star' environment criteria.
• Suitable for direct sun light exposure, but should be top coated with Duram Multithane ATC.
• Permanently flexible ( tests show flexibility > 500% - Class 3 [highest class of extensibility]).
• Will not stain tiles or grout - as Multithane UV is tar and bitumen free.
• Self leveling and seamless membrane (no joints or laps).
• Suitable for immersion in water.
• Can be directly tiled (broadcasting of sand in to final wet coat is recommended).
• Good chemical resistance.
• High strength and puncture resistant.
• Easily repaired and or maintained.
• Odourless (subjective) when cured.
• Formulated to provide long term protection.
• Easy to apply.
• Has good hydrostatic resistance.
• Long history of Australian use.

Precautions in Use

Risk is considered low when properly used but precautions on can, label and / or data sheets should be observed. Use in well ventilated areas. Uncured product is flammable, so keep all sources of ignition away from product and its vapours.

Priming and Surface Preparation

Good preparation is essential. Surfaces must be sound, stable, dry, clean and free of dust, loose, flaking, friable material and substances that may diminish adhesion.


Surfaces should ideally be suitably primed with Duram Primeseal applied at no less than 1 Lt per 4m² or Duram Primeseal SP applied at 7m² per Lt and allowed to dry. 
Duram Primeseal must be used for timber, particle board or bitumen surfaces.
Where there is a risk of evaporation of entrapped moisture in the substrate or water vapour transmission, which may cause the membrane to bubble, two coats of either Duram Primeseal or Duram Primeseal SP must be applied.
Metal surfaces must be clean and free of contaminants and then metal etch primed. If rusted, treat to remove rust, apply a rust converter and then metal etch prime.
Excessively porous, friable and dusty surfaces may require an additional priming coat.
Duram Multiseal maybe used with Multithane.

Allow primers to dry or fully cure before applying the membrane and please refer to the product data sheets of the stated primers.

Detailing Preparation

Prime as required.
Apply an adequate flexible polyurethane sealant, in accordance the manufacture's instruction and tool off to form a solid coved 45º fillet extending at least 10mm on to the adjacent surfaces. Allow to cure. Apply the Duram membrane directly over the sealant and on the adjacent surfaces.
For Additional waterproofing protection the following additional steps should be taken
Lay a strip of Duram Leak-Seal Tape (self-stick, butyl mastic waterproofing membrane with a polyester backed reinforcing fabric) over the cured polyurethane sealant (as described above) pressing it firmly on the surface. Apply the Duram membrane directly over the tape and on the adjacent surfaces.

Joins, gaps and Cracks
Joins, gaps and cracks should be suitably filled and sealed with an appropriate elastomeric sealant, preferably a polyurethane sealant, and allowed to cure.
Recommendation: The movement of small cracks should not be underestimated and should be at least covered with a flexible polyurethane sealant or additional coats of membrane.
Large or Live Cracks
Large cracks should be routed out to form a 'V' and then filled and sealed with a polyurethane waterproof joint sealant as per the manufacturer's instructions. The sealant should be finished slightly proud of the surface and allowed to cure.
After priming, as required, lay a strip of Duram Leak-Seal Tape over the join or crack pressing it firmly on to the substrate. The Duram membrane is then applied directly to the Duram Leak-Seal Tape and extending at least 75mm on to the adjacent surfaces.

If the Duram Leak-Seal Tape is not used then a suitable bond breaker tape (such as duct tape) at least 48mm wide should be laid over the join or crack and apply a fully reinforced Duram membrane consisting of a base coat of membrane in to which the reinforcing fabric is embedded, a saturating coat of the Duram membrane ensuring that the fabric is entirely saturated and covered and then allowed to cure.  At least one or two further coats are applied as per the Duram membrane's Product Data Sheet extending at least 75mm on to the adjacent surfaces.

Joins - Particularly in CFC Sheeting and Timber Sheeting
Ideally the sides of the sheets should be fully coated with a flexible polyurethane waterproof joint sealant prior to butting the sheets together.
If not, the joins should be suitably filled and sealed with an appropriate elastomeric polyurethane waterproof sealant and finished flush with or preferably slightly proud of the surface and allowed to cure.
After priming, as required, lay a strip of Duram Leak-Seal Tape over the join, pressing it firmly on to the substrate. The Duram membrane is then applied as described under 'Large or Live Cracks'.
If the Duram Leak-Seal is not used then follow the procedure as described under 'Large or Live Cracks'.
Waste Outlets, Penetrations and Angles
Waste Outlets: Floor wastes and puddle flanges should be rebated in to the floor to allow water to readily drain. Gaps and perimeters should be sealed with a polyurethane sealant
Plastic or metal angles: Where required by the Building Code such as internal hobs and exterior door barriers and also plastic corner angels under wall boards, they should be securely embedded in to a continuous, gap free bed of a polyurethane sealant / mastic.


Apply Multithane UV by brush, roller, broom and squeegee in a minimum of two coats, usually a day apart so that the minimum dry film thickness in 1.2mm. The minimum wet coat thickness per coat is 0.5mm. 

Reinforced System
In areas such as corners and over joins and cracks the membrane should be used in conjunction with a reinforcing fabric (Duram Durascrim or fibreglass matting). This application consists of applying a base coat in to which the reinforcing fabric is laid followed by the application of a saturating coat ensuring that the product is worked well in to the fabric and that no wrinkles or bubbles are present and that fabric is entirely saturated and covered with product. Allow to cure. Apply one or two further coats of products.

Multitane ATC
Multithane ATC is an aliphatic based polyurethane top coat which extends the life of the exposed membrane.
When top coating Multithane UV with Multithane ATC, allow Multithane UV to fully cure and then apply one good coat of Multithane ATC at the approximate rate of 3 to 4 m²  per Lt.


The stated average coverage rate may vary depending upon type, condition, porosity, texture of the surface and application technique.


Multithane UV: Generally, 1.5 to 2.0 Lts per m² for two coats combined, i.e. 0.75 to 1.0 Lts per m² per coat.  The dry film thickness of the membrane must be at least 1.2mm. 


Generally Grey. Colour may lighten after application. Other colours may be available but minimum quantities apply.

Drying and Curing

Drying and curing of the product is affected by type, dryness and porosity of the surface, temperature, humidity, ventilation, climate conditions and application technique and therefore drying and curing can only be given as a guide.


Generally Multithane UV is weather resistant within 8 to 12  hours with full cure within 24 hours.


Keep in cool, dry place away from heat, flame or combustible material. Product contains flammable solvents. Class 3 dangerous goods must be declared prior to transportation. Available in 1 Lt, 5 Lt and 15 Lt pails.
Self life: 6 - 12 months in unopened container but best used within 6 months. As this is a polyurethane some skinning of the product may occur. This should be cut out and removed. Balance of the product will be suitable for use.

Clean Up

Avoid spills. They are difficult to clean particularly off porous surfaces. for wet spills on concrete and non-porous surfaces use a cloth and Duram Solvent. Do not clean off carpets as it is better to allow product to cure and then shave the carpet. Equipment should be immediately cleaned with Duram Solvent.

Tiling, Topping or Top Coating

Multithane UV can be exposed, covered, topped with sand: cement mix, covered with Geo-textile and pebbles or tiled which will extend its life. If membrane is to be tiled, dry builders sand should be liberally and fully broadcast into the last wet coat to provide a mechanical key. Allow to cure then remove any loose sand. Ensure surface is dry and clean. Two pack, flexible tile adhesives are recommended. Acrylic bonding agents can be used in sand:cement mixes for better strength and adhesion. When tiling, it is essential that adequate expansion joints are installed in accordance with good tiling practice and AS3958.1-1991.

Safety & Precautions

Multithane UV is solvent based. The use of solvent resistant gloves and goggles (against splashes) are recommended. If spraying, which is very rare, the use of self contained breathing apparatus is recommended. If swallowed do not induce vomiting, give plenty of water to drink. Seek urgent medical advice. If in eyes, flush thoroughly with clean water, holding lid open to ensure any trapped product may be flushed away. Seek medical assistance. If on skin, remove contaminated clothing and wash skin with soap and water. This may not remove the product but will encourage it to cure and can later be peeled off. If inhaled, unlikely due to viscosity of the product, remove person to fresh air and apply artificial respiration if required and seek urgent medical attention. Product is flammable when wet. Keep away from all sources of ignition. Ensure adequate ventilation. Vapours may collect in low lying areas.


For full safety data refer to the products Material Safety Data Sheet. Observe precautions as per label.

Tests and Technical Data

Information below is general and approximate. Multithane UV passes the criteria for AS4858:2004 Wet Area Membranes Elongation at break: >500% Class 111 High Extensibility. Resistance to Cyclic Movement: 50 cycles without rupture, tears and crazing.


Issued: 1 May 2002 | Valid to: 31 May 2020

Conditions of Use and Disclaimer

The information contained in this Material Data Sheet is given in good faith based upon our current knowledge and does not imply warranty, express or implied. The information is provided and the product is sold on the basis that the product is used for its intended purpose and is used in a proper workmanlike manner in accordance with the instructions of the Product Data Sheet in suitable and safe working conditions. Under no circumstances will the Company be liable for loss, consequential or otherwise, arising from the use of the product.


DURAM PTY LTD ABN 50 612 836 718
The Ultimate in Waterproofing & Protective Coating Technology

Duram Offices:
NEW SOUTH WALES: 51 Prince William Drive, Seven Hills, NSW 2147

 Tel (02) 9624 4077  Fax: (02) 9624 4079

QUEENSLAND: Unit 4, 29 Collinsvale St Rocklea, QLD 4106

Tel (07) 3255 6478  Fax: (07) 3255 6258