Sika® Concrete Primer
Polyurea primer on cementitious substrates for LAM Roof Waterproofing
Sika® Concrete Primer is a 2-part, polyurea/polyurethane-hybrid primer for cementitious substrates. The rapid curing performance allows overcoating of Sika® Liquid Applied Membrane (LAM) roofing systems after 30 minutes.
- Very good bond strength to substrate
- Reduces the likelihood of outgassing from susceptible substrates
- Helps to stabilise substrates
- Easy to apply
- Can be filled with quartz sand and used as a scratch coat
Usage
Primer on cementitious substrates for use with exterior applications of:- SikaRoof® MTC
- Sikalastic® roofing systems
- Sikafloor® balcony waterproofing systems
Advantages
- Very good bond strength to substrate
- Reduces the likelihood of outgassing from susceptible substrates
- Helps to stabilise substrates
- Easy to apply
- Can be filled with quartz sand and used as a scratch coat
Packaging
11.5 L container | 9.0 L Part A |
Refer to current price list for packaging variations
Colour
Liquid / pale yellow
Product Details
Chemical Base
Solvent-based polyurea
Shelf Life
12 months from date of production
Storage Conditions
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.
Density
~1.02 kg/l (at +23 °C) | (EN ISO 2811-1) |
Application
Mixing Ratio
Primer
Part A : Part B = 3,64:1 (by volume)
Ambient Air Temperature
+5 °C min. / +30 °C max.
Dew Point
Beware of condensation.
The substrate and uncured applied material must be at least +3 °C above dew point
Substrate Temperature
+5 °C min. / +30 °C max.
Substrate Moisture Content
≤ 4 % parts by weight
The following test methods can be used: Sika®-Tramex meter, CM-measurement or Oven-dry-method. No rising moisture according to ASTM (Polyethylene-sheet).
Pot Life
Sika® Concrete Primer is designed for fast curing. High temperatures combined with high air humidity will increase the curing process. Mixed material in opened containers must be applied immediately. In opened containers, the material will form a film after ~1 hour.
Waiting Time / Overcoating
Temperature | Minimum | Maximum |
+10 °C | 60 minutes | 24 hours |
+20 °C | 30 minutes | 24 hours |
Apply an additional coat if 24 hours is exceeded before coating.
Times are approximate and will be affected by changing ambient conditions particularly temperature and relative humidity.
Consumption
~0.13 kg/m² per coat
This figure is theoretical and does not allow for any additional material due to surface porosity, surface profile, variations in level or wastage etc.
SUBSTRATE QUALITY
The supporting structure must be of sufficient structural strength to apply all new and existing layers of the roof build-up. Complete roof system must be designed and secured against wind uplift loadings.
Cementitious substrates (concrete / screed) must be structurally sound and of sufficient compressive strength (minimum 25 N/mm2) with a minimum tensile strength of 1.5 N/mm2.
The substrate must be uniform, firm, smooth and free of any sharp protrusion or burrs, clean, dry, free of grease, bitumen, oil, dust and loosely adhering particles.
SUBSTRATE PREPARATION
Cementitious substrates must be prepared mechanically using suitable abrasive blast cleaning or planing / scarifying equipment to remove cement laitance and achieve an open textured gripping surface profile suitable for the product system 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 cracks, blowholes/voids and surface levelling must be carried out using appropriate products from the Sikafloor®, Sikadur® and Sikagard® range of materials. Products must be cured before applying Sika® Concrete Primer.
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.
MIXING
Scratch coat
Prior to mixing all parts, mix separately Part A (resin) using an electric single paddle mixer or other similar equipment. Add Part B (hardener) to Part A and mix part A + B continuously for 3 minutes until a uniformly consistent mix has been achieved. When Parts A and B have been mixed. Using a forced action / rotating pan / electric double paddle mixer / trough type or other similar equipment (free fall mixers must not be used). Gradually add the required granulometry of dried quartz sand and if required Extender T. Mix for a further 2 minutes until a uniform mix has been achieved. To ensure thorough mixing, pour materials into another container and mix again to achieve a smooth consistent mix. Excessive mixing must be avoided to minimise air entrainment. During the final mixing stage, scrape down the sides and bottom of the mixing container with a flat or straight edge trowel at least once to ensure complete mixing. Mix full units only. Mixing time for A + B + quartz sand = 5 minutes.
Primer
Prior to mixing all parts, mix separately Part A (resin) thoroughly using an electric single paddle mixer (300–400 rpm) or other similar equipment. Add Part B (hardener) to Part A and mix Part A + B continuously for 3 minutes until a uniformly consistent mix has been achieved. To ensure thorough mixing pour materials into a clean container and mix again for at least 1 minute to achieve a smooth consistent mix. Excessive mixing must be avoided to minimise air entrainment. During the final mixing stage, scrape down the sides and bottom of the mixing container with a straight edge trowel or spatula at least once to ensure complete mixing. Mix full units only. Mixing time for A+B = ~4 minutes.
APPLICATION
Strictly follow installation procedures as defined in method statements, application manuals and working instructions which must always be adjusted to the actual site conditions.
Scratch coat
Pour the mixed scratch coat material onto the prepared substrate and apply by trowel or squeegee. Ensure a continuous, pore free coat covers the substrate. If necessary, apply two coats. Confirm waiting /overcoating time has been achieved before applying subsequent products.
Primer
Pour mixed primer onto the prepared substrate and apply by brush, roller or squeegee then back roller in two directions at right angles to each other. Ensure a continuous, pore free coat covers the substrate. If necessary, apply two priming coats.
CLEANING OF TOOLS
Clean all tools and application equipment with Sika® Thinner C immediately after use. Hardened material can only be removed mechanically