Parex® EHI GM
Through coloured mineral-based hydraulic render for use with the PAREXTHERM and PAREXDIRECT render systems. The renders are available in 48 standard colours, can be used in conjunction with the PAREXTHERM and PAREXDIRECT render systems to provide a decorative finish. EHI GM is suitable for manual or spray application and can be finished to a scraped, light tyrolean or heavy roughcast effect. Where a fine grade finish is required please refer to EHI GF.
- Medium Grain
- Range of finishing options
- Can be hand or machine applied.
Usage
- PAREXTHERM External Wall Insulation systems (EWI).
- PAREXDIRECT render systems.
Advantages
- Medium Grain
- Range of finishing options
- Can be hand or machine applied.
Packaging
25 kg bags
Colour
COLOURS
Range of 48 colours
FINISHES
- Medium Scraped
- Spray Textured
- Ashlar cuts
It is possible to acheive a float/sponge/trowel smoothed finish, however this is only recommended for small areas such as smooth bands surrounding windows, plinths and small panels etc. The float sponge/trowel smoothed finish may vary in appearance, particularly due to different factors such as the line and level and condition of the substrate or the appearance of a slurry finish caused by over floating the surface. The latter may produce some micro cracking effect on the render surface which may affect the aesthetical appearance but does not affect its durability. Dark colours are more likely to be affected.
For additional support refer to the data sheet on Textured Mineral Finishes and request the Parex Construction details specific for your application.
Product Details
APPROVALS / CERTIFICATES
- ETA-11-0110 - PAREXTHERM EPS
- ETA-04-0014 - PAREXTHERM SW
Composition
A coloured powder mixed with water, based on cement, hydraulic binders and hydrated lime micronized copolymers, fillers, siliceous sands, mineral pigments and specific admixtures.
Shelf life
12 Months from date of manufacture
Storage conditions
Dry frost free conditions
Maximum grain size
3.0 mm
Reaction to fire
A2 when used as part of an Parextherm EWI system, please consult for further details.
Application
Mixing ratio
5-6 L per 25kg bag
Consumption
Coverage is provided as a guidance only, excludes wastage and will vary subject to substrate conditions and thickness applied.
- Scraped @ 10mm finish, 14 - 16 kg/m2 (1.6 - 1.8 m2 per 25 kg bag)
- Spray Textured, 12 - 14 kg/m2 (1.8 - 2.1 m2 per 25 kg bag)
EQUIPMENT
EQUIPMENT REQUIRED
- Scraping trowel / I Bar.
- Stainless steel spatula.
- Stainless steel smoothing trowel.
- Notched rule and straight edge.
- Wooden float.
- Sponge.
- Clean tools in water after use.
| Application by machine | Spray Render Machine | Constant Mix and Pump Machine |
| Pump Pressure | 10-12 bar (water) | 12 bar / 400 Water flow L/hr |
| Pumping distance/height | Up to 120 m/60 m approx | Up to 50 m/30 m approx |
| Power Source | Diesel | Electric - Based on PFT G4/G5. Other machine settings may differ |
MIXING
- Water dosage: approximately 5-6 L per bag.
- Machine mixing time: 3 to 5 minutes.
- Mixing time cement mixer: 5 minutes approximately.
- Mix whole bag, length of life of mixture approximately 1 hour depending on prevailing conditions.
APPLICATION
- This must conform with the recommendations and specifications for the PAREXTHERM & PAREXDIRECT Mineral render systems and/or as directed by Parex®.
For PAREXTHERM systems to suitable insulations & PAREXDIRECT systems to PAREX approved render boards:
- Apply a 3-5 mm base coat of MAITE, embedded with 355 AVU MESH. (Do not fix the mesh to the insulation and render over it). Leave the surface ridged or combed for receiving the EHI GM or EHI GF. Apply the EHI GM/EHI GF to the desired finish and required minimum thickness as detailed below or as per the Parex project specification.
For other applications consult Parex®.
SPRAY TEXTURED
- Apply a level, compact minimum 10 mm thick coat. Allow to dry and then spray the Textured finish.
MEDIUM SCRAPED EHI GM
- Apply a level, ruled compact 13 mm thick coat, level the surface with a straight edge, spatula or trowel flat. Allow to dry (3-16) hours and depending on the substrate and drying conditions, scrape the surface in small circular motions using a scraping tool, removing no more than 3 mm from the surface.
This scraping process must remove any slight imperfections and bring the application to the specified finished thickness. Each elevation must be scraped at the same stage, as early scraping will result in a slightly darker shade and later scraping in a lighter shade.The minimum finished thickness after scraping is 15 mm.
After scraping, any dust on the surface should be removed by brushing with a clean soft bristle brush. Always stand back and examine the whole surface for blemishes and unevenness. Errors must be corrected at this stage as rectification later is not practical.
RUSTIFICATION/ASHLAR EFFECT
- It is recommended that a minimum depth of render to the back of the rustification/ashlar cut should be no less than 10 mm. To achieve this depth will require the finished thickness of the main render to be increased to approximately 15 - 20 mm.
For ease of application and finish, avoid using AXEL 3000, ALGIREX or 751 LANKOLATEX in the top coat application of the trowel, float or sponge smooth finish.
FAQ
Every building element moves and all movement joints in the substrate must be replicated in the render finish, or cracking will appear. If it is a timber frame, then the movement joints in the timber frame (i.e. between panels) should also be considered in the render, even if they are not replicated in the outer blockwork.
The primary reason is air entrapment within the render and this is caused at application stage when the correct float and serrated spatula or derby tools have not been used to sufficiently aerate the render and break any bubbles to ensure there are no voids within the render.
Render should never be applied to a frozen substrate and the temperature should be 5° and rising before application should begin. Always protect newly applied render from freezing conditions. For more detailed information on cold weather applications, refer to the Technical Information sheet: Cold weather working - General guidance.
This is caused by incorrect application of render, including: applying render to a wet wall; render is applied too thin; masonry joints are recessed or raked out; the mortar used to bond the masonry is of a weak consistency or the mortar joints haven’t had enough time to cure after construction of the masonry.
No, as it will delay the curing time and compromise the chemical bond between the product and the substrate. You may also see efflorescence staining on the blockwork. If this is not removed completely from the substrate before the render is applied, the render will start to break down and delaminate.
There are a number of reasons cracks appear in external render. The most common are the substrate has cracks, bed joint reinforcement has not been applied at every two courses, above and below, or window or door openings or substrates and infill blocks are different strengths, which leads to differential movement. Bed joint reinforcement is a requirement of NHBC, LABC, Premier etc.
If the existing render substrate is well-bonded and there are no surface defects, delamination or cracks, then yes, new render can be applied over existing render.
Sika completed the acquisition of the French company Parex on May 23, 2019. Sika and Parex are two strong companies that are highly complementary in product offering and channel penetration and this acquisition has expanded our product portfolio for the Building Finishing market. Prior to this acquisition, Parex acquired established renders, insulated facades and aggregates company Enewall Ltd, based in Scotland.
Yes, our Mineral Render, External Wall Insulation (EWI) and Pointing Mortar training sessions are aimed at contractors, applicators and distributors who are looking to expand their knowledge or improve skills. Further details can be found on our Sika Wishaw Training Centre web page.
For Applicators and Trade Professionals, Sika Parex render products are available to purchase through our nationwide distributor partners.
You can find details of a local stockist on our web page: Find a Sika Render Stockist.
Please visit our contact us page where you can view an area map displaying contact details for our local Business Development Managers and Specification Managers. Contact details for our Technical Team can also be found on this page should you have any technical queries.