Hydrosil is a highly reflective Fluid Applied Professional Grade Silicone Coating System used to coat all existing roofing substrates.

System includes:

HYDROSIL PROFESSIONAL LIQUID SILICONE ROOF COATING is a professional grade 100% Silicone roof coating. This product is a high performance, solvent based, high solids, single component, moisture cure liquid applied silicone coating. HYDROSIL Professional liquid silicone is an elastomeric yet vapour permeable membrane exhibiting outstanding weathering and water resistance for application to most common roofing substrates.

HYDROSIL SEAM SEALER & DETAILER is a premium silicone multi-purpose mastic for detailing work & to cover all joints/seams prior to the application of Hydrosil (suitable for all roofing substrates). Upon cure, Seam Sealer & Detailer forms a durable, breathable and weatherproof barrier that is highly resistant to degradation from UV and natural weathering.

HYDROSIL HEAVY DUTY REINFORCEMENT ROLL is non-woven, spun bonded 100% polyester and used with HYDROSIL SEAM SEALER & DETAILER to reinforce seams, penetrations, joints or transitions that are subjected to high shear.

Cromar Hydrosil Silicone Roof Coating is a professional grade, solvent based, liquid applied, single component, moisture‐cure premium silicone coating that has been specifically formulated to deliver direct‐ bond adhesion as a restoration and maintenance coating over most common roof substrates and membranes.

Hydrosil forms a durable, vapor permeable, watertight and weatherproof barrier that provides long term resistance to degradation from natural weathering (including extreme temperatures, UV, rain and snow). The coating has excellent UV resistance, dries to a grey finish which keeps roof surfaces cooler preventing thermal shock and extending the life of the roof.

Independently tested and complies and/or exceeds all the requirements of ASTM D 6694 Standard Specification Liquid‐ Applied Silicone Coating used in Spray Polyurethane Foam Roofing Systems.

Hydrosil is approved for Class “A” Non‐Combustible credentials as tested under UL 790 Spread of Flame procedures over most common roofing substrates and membranes.

Note: For professional use only – do not dilute. We cannot assume liability for the results of customers use or a customer’s inability to properly use or apply this product.

A 10-year warranty is offered on this product - Please see Data Sheets tab for more information.

Quick Links - Click To Jump To Section:

• Features & Benefits
• Preparation
• Mixing Procedure
• Application
• Poured In Place Application
• Cure Time
• Cleanup
• Storage
• Limitations
• Technical Data
• Frequently Asked Questions
• What are the recommended coverage rates?
• How quickly will Hydrosil Silicone Coating cure?
• What typical issues could cause failures?
• Do I need to mix Hydrosil Silicone Coating?
• Are there any health & safety risks that I should be aware of and should I wear PPE?
• Are there any substrates the need any extra preparation prior to product application?
• Is the product trafficable/load bearing?
• Can an anti-slip product be added, if so what and how?
• Any advice for cleaning application tools?
• Suitable Substrates

Features & Benefits

• For professional use only
• 10-year material warranty
• Extends the life of the roof
• Single coat application
• Superior adhesion
• No primer required
• Fast cure time
• Highly durable
• Self‐levelling
• Excellent UV resistance
• Unaffected by standing water
• Suitable for use on most common roofing substrates
• Forms a durable, vapor permeable, watertight and weatherproof barrier
• Provides long term resistance to degradation from natural weathering (including extreme temperatures, UV, rain and snow)
• Keeps roof surfaces cooler preventing thermal shock
• Independently tested and complies and/or exceeds all the requirements of ASTM D 6694
• Approved for Class “A” Non‐Combustible credentials

Preparation

• Prior to coating ensure all surfaces are clean, dry and free of dust, dirt, grease, wax and any other incompatible substances. It may be necessary to power wash or prime to enhance adhesion and or limit asphalt bleed through.
• Cover all flashing details, joints & seams using the Hydrosil Seam Sealer and Detailer, ensuring it is thoroughly cured before applying Hydrosil Silicone Roof Coating.

We would advise carrying out a patch test before full scale application - see Instructions for Adhesion Test-Patch (click to download).

Mixing Procedure

Do not thin product with solvent or other solutions. Product may separate during shipping and storage, though it may still look mixed. Mix well before using.

When product is in 18.9Ltr pails, use a 3” min diameter‐mixing blade. Hand mixing with a suitable mixing blade is acceptable. DO NOT OVER‐MIX.

Containers are packaged with a layer of dry nitrogen, to keep latent moisture from prematurely starting the curing process. Once opened, the product has a pot life of 2‐6 hours, depending on relative humidity conditions.

Application

For full application instructions, please refer to the Hydrosil Application Guide (click to download)

• Hydrosil may be sprayed, rolled or brush applied.
• Can be applied over surfaces that exhibit ponding water, however it is advised that all roof systems be designed and built to ensure positive drainage.
• Coating must be evenly applied and pinhole free.
• Hydrosil Coating should be applied at the recommended coverage of 1L/1.25m². Application rates must be checked periodically to assure proper coating thickness. This may be done with a wet film gauge, or by checking coverage of a known quantity. The contractor should estimate coating requirements based on actual experience and needs to figure losses due to applicator experience, surface texture, wind, waste, and other factors increasing estimated litres required.

Poured In Place Application

• Use roller.
• Use smooth or notched squeegee
• Use short bristle brush/roller on smooth substrates.
• Use longer bristle brush/roller on rough substrates.
• After the Hydrosil Seam Sealer & Detailer has thoroughly cured, pour base coat onto roof in a narrow pass for approximately 6 meters and spread with the squeegee or 45 cm applicator brush at an application rate designed to achieve the recommended coverage of 1L/1.25m².
• Immediately back‐roll the area evenly with a 23‐45 cm roller, perpendicular to the squeegee pattern. Care should be taken to back‐roll immediately before coating begins to dry.
• Note: Temperature, coating type, applicator technique, substrate, as well as other factors will affect coating thickness.
• The Hydrosil Silicone Roof Coating shall completely cover all expansion joint covers, parapets and flashings applied at an application rate designed to achieve the recommended coverage of 1L/1.25m².

The roof and substrate should be prepared as per the manufacturer’s specification prior to application of coating.

Note: Temperature, coating type, applicator technique, substrate, as well as other factors will affect coating thickness.

• Hydrosil will be touch dry in 2‐8 hours and will be completely cured and trafficable in no more than 72 hours depending on weather conditions (i.e. temperature and humidity).

Please note: Coating must be evenly applied and pinhole free. Coating must be extended beyond the substrate to create a self‐terminating flashing.

Cure Time

• Dry‐to‐touch in 2‐6 hours.
• Full cure in 4‐8 hours.
• Foot traffic in 24 hours.

Cleanup

Application tools can be cleaned with Acetone. Do not use water!

Cromar Hydrosil cures by reacting with moisture and should not be left in spray guns, pump equipment and/or hoses for prolonged periods unless equipment contains moisture lock hoses, fittings, and seals. Equipment without these components will transmit sufficient moisture vapor to gradually form cured material on hose walls and at unsealed connections potentially causing an increase in operating pressure and material flow restriction.

Storage

Store in a well‐ventilated place between 1 and 23°C. Keep cool. Store locked up. Can be stored in unheated warehouses during the cooler months without the risk of freezing. Keep out of direct sunlight and protect from extreme temperatures.

Shelf Life

18 months from date of manufacture when stored in original, unopened containers between 1 and 23°C.

Limitations

• Do not apply at ambient temperatures lower than 5°C.
• Ensure that all surfaces are not wet or damp and that rain is not imminent during the application time, or for at least an hour after application.
• Always refer to the manufacturer’s specification for application limitations, procedures, and guidelines. Not recommended for continuous immersion service, for use in cryogenic tank, or cold storage roofing applications without a vapor barrier
• It is the user’s responsibility to ensure suitability for use. Read product label and application guide thoroughly before use. Safety Data available on request.

Technical Data

Frequently Asked Questions

What are the recommended coverage rates?

The minimum application rate of HydroSil is a recommended coverage of 1L/1.25m² (wet coating thickness 0.74mm).

How quickly will Hydrosil Silicone Coating cure?

As a moisture cure coating, the Hydrosil Silicone Coating goes from wet to “dry” through the catalyst reaction of ambient and roof temperature (heat) and humidity. Silicone will cure marginally faster in the warmer climates due to humidity and more slowly in colder climates due to reduced heat.

The product containers are packaged with a layer of nitrogen gas to keep latent moisture from prematurely starting the curing process. After opening a container, apply immediately.

The coating will be dry to-touch in 2-8 hours and should be completely cured and a walkable surface in no more than 72 hours depending on weather conditions (such as temperature and humidity). Be sure that rain is not forecasted during application window or for at least 1 hour after application has ended.

What typical issues could cause failures?

Latent moisture in the roofing deck is the primary cause of blisters as the moisture tries to migrate up through the coating. Silicone has low permeability preventing off-gassing from escaping. Insufficient sealing of the seams in combination with insufficient coating coverage will increase the potential for failure. Special attention should be paid to the penetrations, vents, transitions applying the mastic seam sealer properly before coating with the silicone. Preparation is key.

Do I need to mix Hydrosil Silicone Coating?

When product is in 18.9 litre pails, use a 3inch min diameter-mixing blade. Hand mixing with a suitable mixing blade is acceptable. When product is in drums, use a 6inch minimum diameter-mixing blade. DO NOT OVER-MIX. (Overmixing introduces moisture from the air into the coating speeding the curing process.)

Are there any health & safety risks that I should be aware of and should I wear PPE?

Ensure good ventilation of the workstation. Keep away from heat, hot surfaces, sparks, open flames and other ignition sources. No smoking. Wear personal protective equipment. Obtain special instructions before use. Do not handle until all safety precautions have been read and understood. Hygiene measures: Do not eat, drink or smoke when using this product. Always wash hands after handling the product. Store in a well-ventilated place. Keep cool. Store locked up.

Are there any substrates the need any extra preparation prior to product application?

Preparation is the key step in all applications over all substrates. Adhesion of silicone to asphalt is tenacious (always conduct adhesion test) and no primer is needed other than to prevent staining of top-coat.

Any rusted areas on metal substrates should be removed (best as possible) before coating.

Is the product trafficable/load bearing?

The product is not specified for plaza decks, balconies, etc., (Silicone has elastomeric qualities allowing it to move (elongation) with the expansion/contraction of the roof deck).

Can an anti-slip product be added, if so what and how?

Walkable decks typically require “harder” coatings with far less elongation. But as a roof coating you can broadcast granules into the wet coating creating a walkable safety deck.

Any advice for cleaning application tools?

Application tools can be cleaned with Acetone. Do not use water!

Suitable Substrates

Cromar Hydrosil Silicone Roof Coating is suitable for use on:

• Concrete Roofs
• Asbestos Roofs
• GRP Roofs
• Asphalt Roofs
• Bituminous Surfaces
• Metal Roofs
• Weathered Felt Roofs
• Existing Roof Coatings