K REND BASE COATS - Standard UF Base, HP12, HP14, HPX Base

Base coats are applied to substrates as preparation for subsequent coats. Thickness can vary but as for general guidance:

HP12, HP14 & HPX Base              4 – 6mm

Standard UF Base                         8 – 10mm

  • Please see product specification pages for detailed information about application thickness and unusual substrates.

  • Take care when applying the base coat and level with a straight edge to ensure that the next coat is applied flat - Form a light key only.

  • Base coat may take up to 24 hours to cure before further application. 

K REND SCRAPED TEXTURE - Silicone K1 Spray, K1 Spray, Silicone FT, Silicone Spray E Grade

One Coat Application

  • Apply directly to blockwork in 2 passes; the first pass 6-8mm and the second pass 12 - 14mm for a total of 18-22mm.

Two Coat Application

  • The Finish Coat is applied over a K Rend Base Coat (10mm thickness) to line level using a straight edge, to a minimum thickness of 10 - 12mm.

  • When straightening, hollows should be filled out immediately before a skin is formed.

  • Avoid small hollows, which can make it difficult to achieve a good finish. Small areas such as quoins, reveals and bands can be left with a plastic float finish. Do not polish.


  • Scraping should take place when the render has set but has not fully hardened.

  • Setting time varies according to weather conditions - from 4 to 36 hours after application, but typically the render should be scraped the day after application, or as soon as a thumb impression cannot be made but it can be marked with a thumb nail.

  • At the correct time, the aggregate scrapes easily from the wall and does not stick to the scraping tool.

  • Scraping should always be done lightly, & in a tight circular motion to produce a uniform finish.

  • Remove only 1 - 2mm from the complete surface.

  • All areas must be scraped at the same stage of readiness, as early scraping will result in darker shades and late scraping in lighter shades. A uniform approach is essential to achieve an even finish.


  • Immediately after scraping, use a soft brush to remove loose material. This will highlight any unscraped areas, which must then be scraped immediately to avoid colour variation.

  • If scrape patterns or marks are observed, they should be softened by further gentle scraping or brushing. Small blemishes should be repaired at this stage, using material freshly scraped from the wall.


Having scraped the surface level, the ashlar effect is achieved by cutting into the surface with an ashlar cutter to form grooves.
  • Leave a minimum 10mm of coloured K Rend between the recessed ashlar cut and substrate.
  • Additional render thickness should have been applied to accommodate the depth of the ashlar cut. (Typically 20 - 25mm required in areas for ashlar cutting).
  • When forming cuts take care to avoid damaging the arises by working away from the external corner.
  • All cuts must be the same width and depth and set out uniformly as required. 


The following K Rend products can be spray machine applied;

Refina & Strata spray machines are available to purchase. A technical advisory service is also available.

K REND DASH RECEIVER - Silicone Dash, Overcoating Silicone Dash, Silicone Spray Dash

  • Dash Receiver (8-10mm thick) is applied to a K Rend Base Coat (8-10mm thickn).

  • Apply a butter coat of render to a uniform thickness depending on aggregate size (typically 8mm).

  • While the render is still plastic, throw washed aggregate onto the surface to give a uniform dense coverage

  • Immediately tamp the aggregate particles lightly into the butter coat with a plastic float, ensuring a good bond.

K REND ROUGHCAST - Silicone Roughcast

  • Dash Receiver (single coat nominal 6mm thick) is applied to a K Rend Base Coat (8-10mm thick).

  • Allow Dash Receiver to firm but not set and apply Silicone Roughcast (Dashing Coat, see below)

Dashing Coat

  • Always mix a sufficient quantity of Roughcast for the area to be rendered into a bath or box, to ensure that regularity of colour is achieved.

  • Do not add any further water to the mix in the gauging box on the scaffold.

  • Throw the Roughcast on to the surface of the Dash Receiver while the Dash Receiver is still green, using a dashing spoon.

  • Do not go over semi-cured areas to fill in misses, as this can lead to inconsistency of colour.

  • Protect from water during set.

General Information


  • For all K Rend products use approx. 4-5 litres of clean water per 25kg sack.

  • Consistent mix proportions ensures an even finish

  • Mix thoroughly, it takes at least 10 minutes to dissolve the powder additives


  • Product sacks are only shower proof, and should be further protected to prevent damp causing caking of the product.

  • Shelf life is approximately one year if stored in dry conditions in original packaging.

  • Please note that all K Rend products are non-returnable.


50mm samples are provided on request for colour indication only. A test panel from the site is recommended, to ensure satisfaction with the product colour and texture (see below).

Please also note:

  • K Rend materials are manufactured from natural products, and slight shade variations may occur.

  • All rendered areas must be scraped at the same stage of readiness, as early scraping will result in darker shades and late scraping in lighter shades.

  • A uniform approach is essential to achieve a good finish.


  • It is recommended that a test panel (ideally 2m2) be produced for inspection by the customer

  • The test panel should be prepared well in advance of work commencing, and work should not commence until the customer is satisfied with the texture and general appearance of the product.

  • Applicators should be familiar with product water requirement, handling characteristics, setting and hardening times. These may vary according to background, temperature and humidity.


  • For rendering, suitably designed overhangs and flashings should be provided to prevent water washing onto the render and causing staining.

  • At ground level it is recommended that the rendering should not bridge the DPC to form a capillary path for rising damp.

  • Sills and copings should project from the face of the wall with an ample drip groove to ensure that water is kept clear of the render.

  • Gutters and down-pipes must also be designed to keep water off the facade. Angles may be formed using PVC angle and stop beads, or by using chamfered battens.

  • Some construction materials may be susceptible to alkali attack; fittings and surfaces adjacent that are likely to be damaged should be protected.

  • Plan ahead to avoid discontinuity in any one area or walling which could lead to unsightly joints in the rendering.