Sikasil DW is especially suitable for joints in contact with potable (drinking) water, e.g. in the water industry in drinking water reservoirs, tanks, treatment and filtration plants.

Suitable for use on aluminium, anodised aluminium, stainless steel, galvanised steel, powder-coated metals or glazed tiles. May also be used on suitably primed cement-based porous substrates.

Quick Links - Click To Jump To Section:

   
• Features & Benefits
• Surface Preparation
• Application
• Approvals/Standards
• Limitations

Features & Benefits

• One part acetoxy curing silicone sealant
• Good chemical resistance, e.g. to dilute acids High tear resistance
• High UV resistance
• Excellent weathering and ageing resistance

Surface Preparation

• The substrate must be sound, clean, dry and free of all contaminants such as dirt, oil, grease, cement laitance, old sealants and poorly bonded paint coatings which could affect the adhesion of the sealant
• The substrate must be of sufficient strength to resist the stresses induced by the sealant during movement
• Removal techniques such as wire brushing, grinding, grit blasting or other suitable mechanical tools can be used
• All dust, loose and friable material must be completely removed from all surfaces before application of any activators, primers or sealant
• For optimum adhesion and joint durability, the following substrate priming (and/or pre-treatment) procedures must be followed:

Non-porous substrates

Aluminium, anodised aluminium, stainless steel, galvanised steel, powder-coated metals or glazed tiles:

• Slightly roughen surface with a fine abrasive pad
• Clean and pre-treat using Sika Aktivator-205 applied with a clean cloth
• Before sealing, allow a waiting time of > 15 minutes (<6 hours)
• Other metals, such as copper, brass and titanium-zinc, should be cleaned and pre-treated using Sika Aktivator-205 applied with a clean cloth
• Allow a waiting time of > 15 minutes (< 6 hours)
• Glass must be cleaned with Isopropanol before application

Porous Substrates

• Porous substrates, specifically cement-based, must be primed with Sikagard 62 or coated with Sikadur-31 DW.
• For Sikagard 62 before bonding/sealing, allow 30 hours for the Sikagard 62 to fully cure
• For Sikadur-31 DW apply at a minimum thickness of 2 mm, maximum 30 mm, and allow 5 hours / or until hard
• For more details such as application and flash-off times, refer to the most recent Product Data Sheet of the respective pre-treatment product
• Adhesion tests on project-specific substrates must be performed and procedures agreed with all parties before full project application
• For more detailed advice and instructions contact our Technical Department on 0113 2455450 (option 2) or send a message to [email protected]
• Note: Primers and activators are adhesion promoters and not an alternative to improve poor preparation /cleaning of the joint surface
• Primers also improve the long term adhesion performance of the sealed joint

Application

Joint Design

• The joint dimensions must be designed to suit the movement capability of the sealant.
• For joint widths ≥ 10 mm and < 15 mm, a minimum depth or thickness of 6 mm must be applied
• For larger joints contact our technical department on 0113 2455450 (option 2) or send a message to [email protected] for additional information

Consumption

Note: Consumption depends on the roughness and absorbency of the substrate. These figures are theoretical and do not allow for any additional material due to surface porosity, surface profile, variations in level or wastage etc.

Application Method/Tools:

• Strictly follow installation procedures as defined in method statements, application manuals and working instructions which must always be adjusted to the actual site conditions

Masking

• It is recommended to use masking tape where neat or exact joint lines are required
• Remove the tape within the skinning time after finishing

Joint Backing

• After the required substrate preparation, insert a suitable backing rod to the required depth

Priming

• If required, prime the joint surfaces as recommended in substrate preparation
• Avoid excessive application of primer to avoid causing puddles at the base of the joint

Application

• Sikasil DW is supplied ready to use
• Prepare the end of the foil pack, insert into the sealant gun and fit the nozzle
• Extrude Sikasil DW into the joint ensuring that it comes into full contact with the sides or surface of the joint and avoiding any air entrapment

Finishing

• As soon as possible after application, the sealant must be firmly tooled against the joint sides to ensure adequate adhesion and a smooth finish
• Use a compatible tooling agent to smooth the joint surface
• Water can be used
• Do not use tooling products containing solvents

Cleaning Of Tools

• Clean all tools and application equipment immediately after use with Sika Remover-208
• Once cured, hardened material can only be removed mechanically
• For cleaning skin use Sika Cleaning Wipes-100

Approvals/Standards

• This product has been tested to meet the requirements of Regulation 31 (4)(b) of the Water Supply (Water Quality) Regulations 2000.
  • The Secretary of State is satisfied that this product either alone or in combination with any other substance or product in the water is unlikely to affect adversely the quality of the water supplied
  • A copy of test reports to BS 6920-1: 2014 (M 7474P1,2 & 3) are available on request
• Water Regulations Approval Scheme (WRAS), Approval Number: 2203515

Limitations

• Sikasil DW cannot be overpainted
• Sikasil DW Is not recommended for porous substrates, such as natural stone, marble and granite
• Staining from plasticiser migration may occur when used on these substrates
• Preliminary trials must be carried out to check if the substrate experiences staining before full project application
• Do not use for medical or pharmaceutical applications
• Acetic acid released during curing can cause the corrosion of mirror silver and sensitive metals such as copper, brass and lead
• Do not use directly on alkaline surfaces such as concrete, plaster, render and brick
• Do not use on bituminous substrates, natural rubber, chloroprene, EPDM or on building materials which might bleed oils, plasticizers or solvents that could degrade the sealant
• Cure Sikasil DW fully before immersion in water, minimum 4 days up to 14 days (dependent on the temperature, ambient humidity and the thickness of the sealant applied)
• Do not use in totally confined spaces because Sikasil DW requires atmospheric moisture to cure
• If the space is confined suitable ventilation and air supply must be available
• The required vulcanisation or curing time extends with the increasing thickness of the sealant applied
• One component silicones must not be used for bonding applications where the silicone is spread all over the surface
• Such applications require a different type of sealant formulation – please contact our Technical Department on 0113 2455450 (option 2) or send a message to [email protected]