From £20.80 + VAT per bag

Hydraulic lime render for traditional buildings – Baumit Klima RK 39

Baumit RK39 hydraulic lime render is:-

  • an easy to use, creamy white coloured, hydraulic lime based external render.
  • great for all types of solid masonry, historic or modern.
  • suitable as a base coat and a finishing coat.
  • ideal for preventing rain penetration into exposed walls.

Product overview

Where is it used?

  • Baumit RK39 hydraulic lime render can be applied on to all types of dense masonry such as natural stone, brick, concrete block and cast concrete.
  • It can be used as a base coat and a plain finish coat which can then receive decoration with mineral paints and is a very useful all-purpose render/plaster.
  • It contains materials which reduce water penetration so is useful for rendering exposed walls.
  • In locations with Very Severe weather exposure, with an additional coat of Baumit StarContact or MC 55 with StarTex mesh should be applied before finishing.

How is it used?

  • Baumit Klima RK 39 should be mixed with clean tap water (8-9 litres per bag) using an electric whisk to a smooth creamy consistency and applied by hand with a steel trowel.
  • It can also be applied by projection rendering machine.
  • It should be applied as an external base coat at around 18mm thickness and around 3mm as a top coat.
  • It can be applied internally at 10mm for the base coat and 3mm for the finish coat.
  • Baumit StarTex mesh should be incorporated into the outer third of the base coat if the substrate is damp or made of dissimilar materials.
  • The base coat should be finished with a grid plane or scraped with the edge of a trowel to create a suitable key for the following coat.
  • When used as a finish coat it can be trowel or sponge finished.

How much will you need?

Baumit Klima RK 39 has a density of 1.4kg per mm per m² (1mm thickness of plaster over 1m²). Each 35kg bag will cover up to 1.3m² at 18mm thickness.

Frequently asked questions

How long does it take to set?

Setting times vary with temperature and humidity but in the summer the product will usually stiffen enough to finish in a few hours and set hard within 24 hours, depending on the thickness of the applied coat. In winter stiffening may be extended to more than one day with hardening more than two days.

Product videos

Material in action.

Play Video

Baumit RK 39 is a versatile plaster that can be used for many purposes, particularly for historic buildings. Here you can see it being spray applied to the natural stone walls of a cottage, which then has the Baumit StarTex mesh trowelled in to it for reinforcement. Once set, more of the RK 39 was applied as a finish coat.

The lovely creamy, sticky nature and the extremely low shrinkage of the render make it a great product for use on historic buildings, where breathability and flexibility are important.

Pricing & shipping

This product will require one pallet space and so shipping is likely to cost between £50 and £100, depending on where you live. Contact Us for a more accurate costing.

Bag weight (kg) Coverage [m²]Single bag costFull pallet bag cost
351.3m2 @ 18mm£25.56£23.00

Book your free project consultation

We’d like to hear from you. Call us on 01392 861763 or email us at with any questions or comments.

If you can’t seem to find what you need on our website or you have large quantities of materials to purchase please contact us for a chat and we’ll offer you a more bespoke solution.

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