Sikalastic®-625

• CE Marking and Declaration of Performance to ETA 13/0788
• European Technical Assessment ETA 13/0788 based on ETAG 005 Part 1 and 6 - Liquid-applied roof waterproofing using kits based on polyurethane
• External Fire Exposure EN 13501-5:2005, Sikalastic®-625, Exova, Test report No. 328461
• Reaction to Fire EN 13501-5:2007 + A1:2009, Sikalastic®-625, Exova, Classification report No. 328458
• Roof Coverings Exposed to External Fire EN 13501-5:2005 + A1: 2009, Sikalastic®-625, Exova, Classification report No. 323631
• European Technical Assessment ETA 14/0176 based on ETAG 005 Part 1 and 6 - Liquid-applied roof waterproofing using kits based on polyurethane for pre-Coated Metal Roofing Sheets & Fibre Cement Roof Sheets.

Aliphatic polyurethane

9 months from date of production

The product must be stored in original, unopened and undamaged sealed packaging in dry conditions at temperatures between +0 °C and +25 °C. Always refer to packaging.

For ALL Systems
Note:  The application of the system must be approached as one operation.  Always plan for reasonable progress of each coat.  Work only so far in advance that the existing surface can be overcoated as the next operation.  Finish the coating system completely before progressing to the next area.  The ideal time between coats is within 48 hours.

It is not good practice to plan breaks between coats of more than 7 days.  For periods longer than this and less than 14 days the surface must be reactivated with Sika Reactivation Primer. Periods between coats longer than 14 days may affect the normal life term of the system –If this happens consult Sika Technical Services for advice.  Ensure each application/coat is clean and dry prior to overcoating.

At no stage should the Sika Liquid Plastics system or waterproof coating in its finished or intermediate stage be used as a workspace or access floor without adequate protection.

Please note: the above rates are for smooth substrates only. 

Flat Roof Waterproofing Only -  15 year expected durability

Preparation:-  Prior to priming all substrates must be clean dry and sound free from any oxidisation, mould and any other deleterious materials.

Flat Roof Waterproofing Only - 20 year expected durability

Preparation:-  Prior to priming all substrates must be clean dry and sound free from any oxidisation, mould and any other deleterious materials.

Waterproofing of Exposed Trafficable Areas - 10 year expected durability

Preparation:-  Prior to priming all substrates must be clean dry and sound free from any oxidisation, mould and any other deleterious materials.

Waterproofing of Exposed Trafficable Areas - 15 year expected durability

Preparation:-  Prior to priming all substrates must be clean dry and sound free from any oxidisation, mould and any other deleterious materials.

Waterproofing - Buried 20 Year expected durability

Preparation:-  Prior to priming all substrates must be clean dry and sound free from any oxidisation, mould and any other deleterious materials.

Gutters Systems - Stand Alone

Waterproofing - 10 Year expected durability

Preparation:-  Prior to priming all substrates must be clean dry and sound free from any oxidisation, mould and any other deleterious materials.

Waterproofing - 15 Year expected durability

Preparation:-  Prior to priming all substrates must be clean dry and sound free from any oxidisation, mould and any other deleterious materials.

Gutter Joints - Metal Gutters - Bolted Joints/Fixings

Bridge each bolt head/fixing with Sika Flexistrip (minimum 50mm squares) by first removing the backing paper and applying light pressure to the patch edges to fix.

Encapsulate each fixing/joint detail using Sika Reemat Premium patches, cut to requirements and bedded in Sikalastic®-625 applied at a minimum wet film thickness of 1000 microns.  Allow to dry before continuing with the overall waterproofing.

Apply the fully reinforced system through the metal gutter as specified.

Gutter Joints - Metal Gutters - Bond Break

Introduce a 'bond break' at each gutter joint by first laying 50mm (minimum width) low tack de-bonding tape centred on the joint.

Apply a 'stripe' coat (200mm wide) of Sikalastic®-625 to each seam/joint at a minimum wet film thickness of 1000 microns and whilst wet, Sika Flexitape Heavy (150mm) using a loaded brush to obliterate the tape.  Allow to dry before continuing with the top coats.

Asbestos & Profiled Metal Roof Sheets

Waterproofing Only - 10 Year expected durability

Preparation:-  Prior to priming, all substrates must be clean, dry and sound, free from any oxidisation, mould and any other deleterious materials.

Tape Embedment:-  Prior to the main first and second coats, a light coat of Sikalastic®-625 must be applied to the surface and edges of Sika Joint Tape SA® and allowed to cure.  The purpose of this is to waterproof the surface of the tape and ensure that the surface of the fabric is fully embedded in the main coating.  This can be applied using a roller or brush.

Waterproofing Only - 15 Year expected durability

Preparation:-  Prior to priming, all substrates must be clean, dry and sound, free from any oxidisation, mould and any other deleterious materials.

Tape Embedment:-  Prior to the main first and second coats, a light coat of Sikalastic®-625 must be applied to the surface and edges of Sika Joint Tape SA® and allowed to cure.  The purpose of this is to waterproof the surface of the tape and ensure that the surface of the fabric is fully embedded in the main coating.  This can be applied using a roller or brush.

Asbestos & Profiled Metal Roof Sheets - Localised Reinforcement for Roof Areas Only

Sheet End Laps

Prepare and prime the corrugate roof sheet as appropriate.

Apply 6" (152.4mm) wide of Sika® Joint Tape SA to prepared substrate.  Remove 4–6” (10.2–15.2 cm) of release liner from underside of the Sika Joint Tape SA and position the tape centrally across the lap joint of the top and bottom sheet, and pressing firmly into place.

Continue to remove release liner, whilst moving across the lap joint.

Be careful to follow the profile of the metal sheet and ensure full and even contact.

Ensure that the tape overlaps any end lap fixings by at least 25mm. Where this cannot be achieved, a separate piece of 3” (76.2mm) should be used to reinforce each fixing.

Once in-place, always apply additional pressure to the surface to fully activate the bonding process, compress any creases and remove any trapped air.  Use a hard roller for best results.

Side Laps

Apply 6" (152.4mm) wide Sika® Joint Tape SA to the prepared substrate.  Remove 4–6” (10.2–15.2 cm) of release liner from the underside of the Sika® Joint Tape SA.

Position the tape centrally across the joint, and press into place.  Continue to remove release liner, whilst moving down the joint and pressing firmly onto the substrate surface.

Ensure that the tape overlaps any side lap fixings by at least 25mm. Where this cannot be achieved, a separate piece of 3” (76.2mm) should be used to reinforce each fixing. 

Once in-place, always apply additional pressure to the surface to fully activate the bonding process, compress any creases and remove any trapped air.  Use a hard roller for best results.

Bolt Heads & Fixings

3" x 5" (76.2mm x 130mm) is used to reinforce the following fixings scenarios:

• Where the 6” (152.4mm) tape cannot encapsulate the lap fixing by 25mm and separate reinforcement is required – as outlined above.
• For all non-lap fixings

Method One:

Using the 3” (75mm) wide roll, cut a piece of tape which is approximately 3” x 4” (76mm x 100mm) in size and remove the release liner.  Turn the tape to a diamond shaped position and press firmly into place centrally over the fixing.

Method Two:

Using the 3” (75mm) wide roll, cut a piece of tape which is approximately 3” x 5” (76mm x 130mm) and remove release liner. Ensure that at least 3” inches of the tape is pressed down tightly above the bolt with no creases.  Pull the remaining 2” over the bolt-head and press down into place, ensuring that all creases are rolled flat.

On all localised reinforcements, the firmer the pressure applied, the faster and stronger the bond.

Resistant to mild acids, alkalis, detergents and some solvents.  Contact Sika Technical Services for additional information.

Prohesion testing to ASTM G85-94;  Annex A5 (1000 hours cyclic exposure) and cyclic salt fog/UV-A exposure to ASTM D 5894 (6 cycles totalling 1000 hours)

-30°C min. / +80°C max - Intermittent

+2°C min. / +30°C max.

20% min. / 85% max.

+2°C min. / +30°C max.

Beware of condensation.
The substrate and uncured applied product must be at least +3°C above dew point to reduce the risk of condensation or blooming on the surface of the applied product.  Metal surfaces will be more prone to temperature fluctuations occurring and wind chill effects.

≤4 % parts by weight.  
Test method: Sika®-Tramex meter
No rising moisture according to ASTM (Polyethylene-sheet).

For consumption rates and waiting time/overcoating, refer to the individual Product Data Sheet of the appropriate cleaner and primer.  Other substrates must be tested for their compatibility.  To ensure compatibility, carry out preliminary trials.

~1–2 hours

The material in opened containers must be applied before a surface skin occurs.

Times are approximate and will be affected by changing ambient conditions particularly temperature and relative humidity.

~48 hours

For longer periods up to 14 days, the surface must be reactivated with Sika Reactivation Primer.

Times are approximate and will be affected by changing ambient conditions particularly temperature and relative humidity.

Apply Sikalastic®-625 using a roller (short pile mohair roller), brush (soft nylon or bristle brush).

General

All dust, loose and friable material must be completely removed from all surfaces before application of the product and associated system products, preferably by vacuum extraction equipment.

To confirm adequate surface preparation and Sikalastic®-625 adhesion, carry out a preliminary trial before full application together with adhesion tests as required.

Concrete and Cementitious Substrates

Substrate must be structurally sound, clean, dry and free of all contaminants such as dirt, oil, grease, coatings, laitance, surface treatments and loose friable material.

New concrete should be cured for at least 28 days.

Substrates must be prepared mechanically using suitable substrate preparation equipment to remove cement laitance and achieve an open textured gripping surface profile suitable for the product thickness.

High spots can be removed by grinding.

Weak cementitious substrates must be removed and surface defects such as blow holes and voids must be fully exposed.

Repairs to the substrate, filling of joints, blowholes/voids and surface levelling must be carried out using appropriate products.  Products must be cured before applying Sikalastic®-625.

Outgassing is a naturally occurring phenomenon of concrete that can produce pinholes in subsequently applied coatings.  The concrete must be carefully assessed for moisture content, air entrapment and surface finish prior to any coating work.  Any requirement for priming must also be considered.  Installing the membrane either when the concrete temperature is falling or stable can reduce outgassing.  It is generally beneficial, therefore, to apply the embedment coating in the late afternoon or evening.

Brick and stone

Thoroughly clean by power wash and allow to dry. Where there is a risk of algal re-growth on absorbent surfaces use Sika Biowash. Refer to the individual Product Data Sheet.  Repair any spalling, flaking or other damage and replace any missing jointing.

Asphalt

Thoroughly clean by power wash and allow to dry.  All major cracks should be sealed to allow continuity of the Sikalastic®-625 system.  Asphalt must be carefully assessed for moisture and/ or air entrapment, grade and surface finish prior to any coating works being carried out.  Any priming requirement must also be considered.

Bituminous felt

Felt must be firmly adhered or mechanically fixed.  Thoroughly clean by power wash and allow to dry.  Treat blisters by star cutting and removing any underlying water.  Allow to dry and re-adhere using Decostik® SP.  Badly degraded areas should be replaced with S-Vap 5000E SA or S-Vap HD bonded as specified.

Bituminous coatings

Bituminous, volatile mastic or old coal tar coatings must be rigid and without a sticky surface. Remove loose, degraded and tacky coatings.

Single ply

Various types of single ply sheeting can be coated subject to adhesion/compatibility tests.  Contact Sika Technical Services for additional information.

Metals

Ferrous metals must be in a sound surface condition.  Surfaces must be clean, free from rust, oil, grease, existing loose or degraded coatings etc. Prepare surfaces to a bright metal finish using suitable preparation techniques taking into account environmental conditions.

Non-ferrous metals must be in a sound surface condition.  Remove any deposits of dust and oxidation and abrade to a bright metal finish.  Wire brushing can be used for soft metals such as lead.  Surfaces must be clean, free from oil and grease, which, if present, must be removed with a proprietary de-greasing solution.  Then wash with detergent, rinse and dry.

Wood

Wood and wood based panel roof decks must be a minimum 18mm thick and certificated to conform with BS EN 1995-1-1: Eurocode 5; in good structural condition, firmly adhered or mechanically fixed.

Wood based decks require a complete layer of Carrier Membrane SA before the application of the chosen Sikalastic®-625 system. The substrate must be primed prior to the Carrier Membrane SA adhered to the timber deck.  Small timber protrusions must be flattened by locally planing or sanding to provide a smooth surface.

Paints/Coatings

Remove loose or degraded coatings by suitable preparation techniques to provide a feathered firm adhering edge. Remaining coatings can be overcoated if soundly adhered. Ensure the surface is clean and free from oil, grease etc.

Existing Sikalastic®-625 system

Clean the membrane surface using a power wash at ~14 N/mm² (2000 psi) including detergent then rinse thoroughly and allow to dry.

Sikalastic®-625 is supplied ready for use, gently stir until a uniform colour has been achieved.  Over mixing must be avoided to minimise air entrainment.

Accelerated

Before use slightly stir the Sikalastic®-625 then add the full Sika® PU Acclerator unit (180ml Sika® PU Acclerator for 15L of Sikalastic®-625) and stir using a drill and paddle until a uniform mix has been achieved.

Over mixing must be avoided to minimise air entrapment.

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

General

Always begin application with detailing before installation of the main horizontal surfaces.

Primer

Apply the appropriate mixed primer onto the prepared substrate and apply by brush or appropriate roller.  Ensure a continuous, pore free coat covers the substrate.  Confirm primer waiting/overcoating time has been achieved before applying successive products.  Refer to individual primer Product Data Sheet.

Base coat

Apply the Sikalastic®-625 onto prepared substrate the same width as the Sika® Reemat Premium and apply evenly by brush (soft nylon or bristle brush) or roller (short pile mohair roller) at the required consumption rate in 2 directions at right angles to each other.  Alternatively spray Sikalastic®-625 with suitable equipment.

Reinforcement

Roll in the Sika® Reemat Premium reinforcement whilst Sikalastic®-625 is still wet ensuring there are no bubbles or creases in the reinforcement. Reinforcement overlaps must be a minimum of 50 mm.  Recommendation is to work 1 metre at a time lengthways applying 1st coat and embedding reinforcement.

Top coat

Apply the Sikalastic®-625 onto the applied reinforcement layer and apply evenly by brush or short piled roller at the required consumption rate in 2 directions at right angles to each other.  Confirm overcoating times before application.  Alternatively spray Sikalastic®-625 with suitable equipment.

Ensure each application/coat is clean and dry before applying next coat.

Clean all tools and application equipment with cellulose thinners or xylene immediately after use. Hardened material can only be removed mechanically.