From £24.83 + VAT per bag

Internal hydraulic lime plaster – Baumit RK 38

Baumit RK38 internal lime plaster is:-

  • a vapour permeable (breathable), natural, hydraulic lime plaster, creamy white in colour.
  • ideal as a base coat and top coat plaster for all types of masonry.
  • suitable as a base coat plaster for wet areas.
  • a healthier alternative to cement or gypsum plasters.

Product overview

Where is it used?

  • Baumit RK38 is used as base coat for the whole interior of the building.
  • Because of it’s high breathability it can be used as a base coat in wet areas such as bathrooms and kitchens and can also be used as a plain finish plaster.
  • Because of the fine aggregates used it is suitable for finishing with Baumit Klima Glatte, a very fine hydraulic lime finish plaster.
  • As a finishing coat for a more traditional feel.

How is it used?

  • Baumit RK38 should be mixed by a plaster whisk with clean tap water to a smooth consistency and then applied by hand or it can be spray applied by machine.
  • It is typically applied at a thickness of 10-12mm on to sound substrates but can be applied in layers up to 20mm thick if required.
  • Greater thicknesses can be achieved but must be made up in layers of at least 10mm thickness.
  • Coats should be gently finished with a grid plane or scraped with the edge of a trowel prior to application of further coats or any finishing plasters.
  • Finish coats should be applied at around 3mm in thickness with a trowel or spatula and then sponge finished with a fine sponge.

How much will you need?

Baumit RK 38 has a density of 1.3kg per mm per m² (1mm thickness of plaster over 1m²). Each 35kg bag of Baumit RK 38 will cover up to 2.2m² at 12mm thickness or 8.5m² at 3mm 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 overnight. In winter stiffening may be extended to more than one day with hardening more than two days.

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
352m2 @ 12mm£24.07£21.67

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