From £17.64 + VAT per bag

Breathable Insulating Plaster – Baumit DP 85

Baumit DP85 insulating plaster is:-

  • for insulating internal and external areas of masonry walling.
  • great for prevention of mould growth on internal walls.
  • ideal for insulating old buildings where space is restricted.
  • a great way to insulate but retain the character of the building.

Product overview

Where is it used?

  • Baumit DP 85 insulating plaster can be used internally or externally and is ideal for use in old stone or brick buildings where vapour permeability is important.
  • It should not be used at plinth level on the exterior.

How is it used?

  • Surfaces should be clean, dry and free of dust and salts.
  • Baumit DP85 should be mixed with clean tap water and mixed with a plaster whisk to a smooth creamy, lump free consistency and applied by hand or by projection plastering machine.
  • The best consistency is achieved by mixing, leaving to stand for 5-10 minutes and then re-mixing, giving a nice sticky plaster.
  • Baumit DP85 can be applied at a minimum of 30mm or up to 50mm in one coat.
  • Further coats of Baumit DP85 can be applied to bring the maximum thickness up to 100mm. Each coat should be flattened off and the surface textured with a nail or grid float. Allow 1-2 days between coats.
  • After curing a 5mm coat of Baumit MC55 with Baumit StarTex mesh should be applied before any finish coats.

How much will you need?

Baumit DP 85 has a density of 0.18kg per mm per m² (1mm thickness of plaster over 1m²). Each 9kg bag (50 litres) of Baumit DP 85 will cover up to 1.6m² at 30mm thickness or 1m² at 50mm 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 solid overnight. This should be left to cure at 10mm per day before applying any further plaster layers.
  • In winter setting times and curing times will lengthen due to lower temperatures and higher humidity.

Is it breathable enough for old buildings?

  • This product does contain a small amount of cement and the main insulation is provided by polystyrene beads, both of which sound like they might not be suitable for older buildings. However, the vapour permeability of this product has been engineered to be even higher than traditional lime putty or hydraulic lime plasters making it ideal for very permeable substrates. It is also a fairly soft product once it has dried and so does not do any damage to historic building materials.
  • Over the course of 2018 we had extensive dialogue with Historic England about this product and after a great deal of scrutiny they did allow it to be used on the restoration of a 700 year old granite property in Dartmoor National Park. They are extremely conservative when it comes to accepting new materials for use so we’re very excited they allowed us to use the DP 85 for this project.

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
91m2 @ 50mm£19.60£17.64

Book your free project consultation

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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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