Designed for application over difficult substrates as primary key coat.

The strongest adhering render in the range. Coverage for key coating is approximately 8-10 m2 per bag.

Product size: 19kg bags
Coverage: 8-10m2
Substrate suitability: New & / or Old Brick, In-situ Concrete (Rough), Fibrous-Cement Sheeting
Application tools: Trowel
Dry time: Minimum 72 hours after application, and ensure fully cured (12% WME or less) before overcoated with Unitex Texture
Safe Use: Refer to the MSDS


Application & Fixing Guide



Size: 19kg bags

Coverage: 8-10m2

19kg Bag – New & / or Old Brick,
In-situ Concrete (Rough), Fibrous-Cement Sheeting

Apply with: Trowel

Safe Use: Refer to the MSDS 

Unitex® Polymer Render is a trowel-applied acrylic filling and levelling compound, suitable for application on dry, non-porous and difficult surfaces. Unitex® Polymer Render is also used for patching, levelling, skim coating and restoration of damaged surfaces. Unitex® Polymer Render is the strongest adhering render available from the Unitex® range of speciality render products.

Unitex® Polymer Render is designed for use over FRC sheeting as a levelling preparation skim coat and is trowel applied prior to over coating with Texture from the Unitex Applied Finishes range.

Approximate coverage per  bag is 8-10m² (over reasonably level FRC sheeting).

Once the Unitex® Polymer Render is on the wall it must be trowel finished with speed immediately, as this type of modified render tends to dry from the surface first. Unitex® Polymer Render is not recommended for application where coating thicknesses greater than 5 mm are required.

Note: All Unitex® Render products are designed to be over coated with a Unitex® Applied Texture and two coats of Uni-Flex PTC™.

Condition of Substrate

The substrate surface must be dry, cleaned free of any grease, oils, scaling laitance, efflorescence, form-oil compounds, mould, fungi, rust, dirt, dust or any other foreign matter.

It is the responsibility of the Builder or Head Contractor to make good any substrate before the render is applied.

Adequate expansion joints are required to minimise cracking on the surface of the render. Location of the expansion joints is also the responsibility of the Builder or Head Contractor. Unitex® recommends expansion joints to every elevation and between different substrates, to allow for building movements and or stresses. Ideally, expansion joints should be at all penetrations to wall surface.

If such expansion joints are not provided by the Builder or Head Contractor, cracking due to movement of the substrate may occur. This is in no way indicative of faulty material. Rather it indicates sub-standard building practice.


In dry, mild conditions, Unitex® Polymer Render should be dry after 72 hours after application. When dry, Unitex® Polymer Render can be overcoated with a texture from the Unitex Applied Finishes range. With certain site conditions such as shaded areas, lower temperatures or high humidity, curing of the render may take longer, even up to 7-10 days. Prior to overcoating with Unitex texture, base coat must achieve a minimum of 12% WME. Always check the weather forecast before applying renders to masonry surfaces as rain, especially within the first 8 hours after application, has a tendency to damage and weaken the render or at best, leave water marks. Heavy rain at any time during the initial 2-3 weeks may leave water marks on the surface. Should rain damage occur, the render integrity and adhesion must be checked, and any necessary repairs carried out and then allowed to fully dry prior to allowing Unitex® Polymer Render to be overcoated.

Both frosty conditions and excessively high temperatures should be avoided. Unitex recommends applying Unitex® Polymer Render in temperatures greater than 8ºC and less than 30ºC. Should hot and windy conditions be encountered after commencing rendering, dampen the substrate with water. Do not apply render until the “wet” look has receded and the surface has absorbed the free water. This will enable Unitex® Polymer Render to remain as workable as it is in milder conditions.

Unitex® Polymer Render:

  • Trowels on easily, smoothly and thinly
  • Is the strongest render in the Unitex Renders Range
  • Is more waterproof than conventional render
  • Ideal for patching, levelling, skim coating and restoration of damaged surfaces
  • Ideal for FRC sheeting
  • Just add water (19kg bag)

Step-By-Step Instructions for FRC Sheet

  1. Apply the mixed Unitex® Polymer Render to the sheet gaps and embed the pre-cut (50 mm) Uni-Mesh (alkaline resistant). Allow to dry fully before step (2).
  2. Skim coat with Unitex® Polymer Render over whole of FRC Sheet surface with a steel or perspex trowel to a depth of approximately 2-3 mm. If studs behind the sheet are uneven then use Unitex® Polymer Render a little thicker to feather out the worst of the unevenness.
  3. When the Unitex® Polymer Render is through dry and cured for minimum 48 hours, in temperate conditions, overcoat with any of the Unitex® range of applied finishes (eg Uni-Trowel Décor, Uni-Roll Décor).
  4. The system requires the above (when through dry) to be over coated (by roller) with one coat of Uni-Flex Membrane (wet 011, or Dry 811) at a rate of approximately 2m² per litre or two coats of Uni-PTC (Unitex® Protective Top Coat 111).

Guide to Good Mixing Consistency (19kg Bag)

  1. Add the contents of the bag slowly to 4 litres of water (25% volume of entire bag) with vigorous drill mixing to ensure a lump free render of required slump.
  2. The mix can be later water thinned to required viscosity.
  3. Ensure wall surface is stable, clean, dry and free of dust, etc prior to application.
  4. For difficult masonry and non-masonry surfaces contact Unitex for product and surface preparation advice.