Limecrete Floor

The original Limecrete Floor is a modern interpretation of a traditional solid lime or gypsum floor that can still be seen in many historic or well preserved older homes.  

Mike Wye offer an option for an insulated Limecrete Floor using an insulating, coated clay aggregate as an effective capillary break. Clay aggregate can also be incorporated into the slab rather than using sand to further improve thermal insulation .

Limecrete floors offer a number of advantages:

  • Provides a capillary break to effectively manage ground moisture.
  • Can be designed to meet the insulation requirements of Building Regulations and beyond.
  • ︎Natural and environmentally friendly compared to modern floor systems.

The majority of Limecrete Floor systems now use foam glass aggregate as the sub-base (see Glasscrete).

The original form of Limecrete Floor using expanded clay aggregate can still be beneficial for small projects or where a whacker plate cannot be used.

Limecrete Example Specification

  1. Levelled and compacted ground.
  2. Layer of geotextile membrane.
  3. 100 mm – 500 mm layer of loose fill 10-20 mm Coated Techniclay.
  4. Layer of geotextile membrane.
  5. 100 mm – 150 mm Limecrete slab, 3 parts Un-coated Techniclay to 1 part NHL5 (by volume) with 30 mm Cork Board to external perimeter walls.
  6. 75 mm screed of 2 parts sand 1 part NHL5 (to bed heating pipes if included).
  7. Adhere Cal tile adhesive for floor tiles or preferred floor finish. 


labc_4890 Reg_RegDetails

Mike Wye Limecrete and Glasscrete® are LABC registered floor systems. LABC represents all local authority building control teams in England and Wales. Members work cooperatively with building owners, home owners, architects, plan drawers, developers building contractors and other professionals to ensure buildings are safe, healthy and efficient to meet the standards set by the building regulations.


Calculating volumes and insulation U-values can be complicated. Just tell us what you need and we will work it out. We will calculate all the design information you need for your floor, thicknesses, insulation values etc using our accredited design programme. As well as providing quotations, including delivery, for all the components. 


Techniclay Lightweight Expanded Clay Aggregate

Expanded clay aggregate consists of lightweight, porous, ceramic granules formed by expanding special clay at high temperatures.

The Coated Techniclay aggregate is free-draining, has negative capillary action and has good thermal qualities (k = 0.10 W/mK). It is used as an insulating layer below the limecrete slab.
This is the functional part of a limecrete floor, offering an effective capillary break as well as thermal insulation.

Mix the Uncoated Techniclay with natural hydraulic lime (NHL 5) to form the limecrete slab.

The graph below shows represents simple test on moisture absorption and forms the basis for a minimum of 120 mm of loose fill material for an effective capillary break.

limecrete graph

Water suction height above water surface and moisture content in kg/kg for the individual layers

Natural Hydraulic Lime

Secil NHLs have been available since 1891 and have made a huge contribution to the construction market in Portugal. 

We believe Secil NHLs offer a high quality option for those wanting to use powdered limes in their work.

Secil NHL5 is fast setting and ideal for limecrete floors when used with a suitable aggregate such as Techniclay ‘light expanded clay aggregate’. 


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