Multipro Resistant Board
Timber Structural Studwork
The Hemcrete® Frame system is a combination of Hemp and a lime based binder that forms an environmentally friendly building material. This material is cast ‘in situ’ around our structural timber frame system, to give high levels of insulation, air tightness and vapour permeability.
The wall construction uses the ‘Breathing Wall’ principal, as it allows moisture laden air to pass through the structure, whilst maintaining the thermal performance. In addition the structure acts to maintain the building at a constant temperature.
• The system utilises materials from sustainable, renewable sources of supply
• Excellent Thermal, acoustic and air tightness properties
• Cost effective solution compared to traditional masonry construction
of equivalent performance
• Reduces the CO2 content in the construction process
• Continues to take CO2 out of the air for the life of the building
• Is a Sustainable Home
The Hemcrete® Frame system is provided its structural strength by the timber studwork, its racking strength by the internal RESISTANT Multi-Pro lining board which also acts to retain the hemp. Insulation is provided by the Hemcrete® itself. Hemcrete® is not a load bearing material and does rely on the timber frame to carry the loads of the roof and upper floors to the foundations.
The timber frame is usually positioned to the internal of the wall structure so that the Hemp and Lime binder mixture completely surround the external of the frame ensuring that cold bridging does not occur. The lime binder provides an excellent preservative treatment which means that there is no need for any chemical treatments to be used on the timbers, and, as it only takes just 14 weeks to grow sufficient hemp on one hectare of land to produce one house, the cost to the environment is minimal.
The Hemcrete® Frame system is mixed on site usually using a pan mixer or machine mounted mixing bucket. Mixing ratios are provided and it is important that the two components are mixed efficiently, adding water at the specified rate.
The mix is then poured into either temporary or purpose design shuttering and lightly tamped into place. It is suggested that the material is placed and tamped in 300mm layers with no limit on the number of layers placed in a day.
The shuttering is left in place for 24 hours for the initial set to occur. The system can then be finished using either Mineral Lime based renders. While timber cladding, tile hanging or brick and stone facings are also options.
When building with Hemcrete® Frame, it is recommended that it stays protected from extreme weather conditions and temperatures below 3 degrees centigrade.
The system needs protection from rising dampness and falling rain, during construction and is not designed to be used below D.P.C levels.
Guide to U Values 90mm Timber Frame Wall
Depth of Wall U Value. W/m2K
300 mm 0.23
400 mm 0.17
500 mm 0.14
600 mm 0.11
The above figures are based on having a minimum covering of 100mm of Hemcrete® to the weather side of the timber frame structure. Care should be taken when choosing external finishes to ensure that the vapour permeability of the system is not altered.
VIDEO Constructing with Hemcrete® click here
View Irish Eco Homes Timber Frame with Hemcrete Construction
Tradical® Hemcrete® literature is available in PDF for easy downloading and printing
Resistant Multipro literature is available in PDF for easy downloading and printing