Variant 1: As a non-load-bearing brick wall
Brick length 55, height 20cm, thicknesses 8, 12, 20, 30, 38 and 44cm. For the calculation in Baumeister Devis, approx. 50chf/m2 can be assumed for the brick plus the normal piecework rates for bricklaying. We have several hundred pallets of bricks and cement-free mortar in stock. See webshop (quantity discounts from 10 pallets)

Variant 2: Concreting prefabricated timber stud walls
The industrialisation of hemp lime insulation has succeeded with the CANCRET AG (in foundation) patent and can now be used globally. With a mobile hempcrete production plant, classic timber frame elements are concreted at the timber builder’s premises or in a field factory close to the construction site. As a guideline for planning, a production volume of 30-50m2 per day and costs of 200chf/m2 can be assumed. The mobile mixing plant and the raw material can be hired from us, either in-house or externally. We are at your disposal for specialised planning. (140 chf/hour)

Important: The CANCRET AG patent replaces the entire conventional wall structure in timber construction (wind paper, OSB, insulation, Fermacell, etc.). Our recommendation is a 20 mm stud that is concreted over by 12 cm and plastered with lime on both sides. (see U-values)

Variant 3: Hemp tamping on the building site with ‘climbing formwork’
Conventional method practised for decades with (climbing) formwork on site. See relevant YouTube videos and SRF report from May 2023).
With prices of CHF 600-900/m2, we are in the area of hobby and single-family house art similar to rammed earth. We do not offer this work and recommend craftsmen from hemp rammed earth collectives in DE, AT and CH. Of course, we also provide our mobile hemp mixer for this work.

Extensive drying is necessary for variants 2 and 3. We recommend additional mechanical ventilation. (Fan available for hire from us)

Facade design
Beauty is in the eye of the beholder. Some builders and architects enjoy a visible hemp lime façade that is simply slurried. The basic prerequisite is that there are large overhanging roofs so that the hempcrete is protected. We also recommend careful specialist planning to ensure that the connections and seals are clean. In principle, variant 2 also provides beautiful homogeneous visible surfaces. Either way, a joint pattern is always to be expected.

We advise against open hemp façades, especially on the north side. Due to the diffusion-open wall structure, we sometimes notice damp walls. Our recommendation is therefore a classic lime plaster inside and out, which is supplied by various manufacturers with corresponding guarantees and is applied by all plasterers. (Smoothed reinforcement recommended)

Hempcrete only achieves minimal static properties and should therefore be used in combination with a disc/column construction. (Timber construction recommended)

44 cm without plaster: U-value 0.15
30 cm without plaster: U-value 0.22

30 cm with 6 cm thermal plaster: U-value 0.16
30 cm with 8 cm thermal plaster: U-value 0.15

38 cm with 4 cm thermal plaster: U-value 0.15

Recommended wall construction for multi-storey buildings (for EI60) sorted by price in ascending order:

A): CANCRET System 12/20/with 6cm thermal plaster
B) 44 hemp bricks from Schönthaler with normal plaster
C) CANCRET System 12/20/12cm with normal plaster (either inner or outer layer bricked)

CANCRET AG’s horizontal production process was developed and industrialised for our pilot project. We used around 1500m2 of timber system walls, which we produced with CANCRET in 30 days, and 2600m2 of hemp brick walls. The OPENLY construction system is freely available to everyone.

Hempcrete benefits from the rapid carbon sequestration of the plant Cannabis sativa ssp. sativa. Through its photosynthesis, carbon from the air is stored in a stable form in the fibres. The hemp shavings in our dade CANCRETE consist of 49 % carbon. 1 kg of hemp stores approx. 1.7 kg of CO2.

Hemp is grown once a year in Switzerland and is a real alternative to the widely used ‘feed maize’. It can be produced locally and harvested with the same combine harvesters (= no additional investment for farmers). It would even be possible to grow it twice a year. Our hemp currently comes from France.

By summer 2024, together with Carbon Standard International, we will be able to provide a global standard for a CO2 certificate on hempcrete. (Global Material C-Sink). This is exciting for processors (additional income) and building owners for insetting, as the operational business can be neutralised with their own construction activities. You can find more information here.