The stone façades were repaired and the interior was redesigned to include spaces that would be open to the public, an exhibition space, a documentation centre, a cafeteria and a meeting room.
An indoor walkway open right up to the roof of the building was created to encourage interaction and provide natural ventilation that flows through the building, which is key to thermal comfort in summer.

Local and renewable energy-efficient materials were used, such as wood, hemp and so on.

There was an emphasis on quality in terms of the urban context, use and energy efficiency – by optimising indoor humidity and acoustic levels – and energy and water management.

This comfort is provided by the insulation, the heating system and the ventilation system.
The client opted for a Tradical^® Hemp Render insulation solution. Thanks to the breathability of the render, it was a perfect match for the existing architecture: half-timbering on the inside of the building and thick high-inertia stone and brick walls (see the cross-section in the Tradical^® Hempcrete brochure, p.21)

Tradical^® Hemp Render also helps to absorb ambient noise.

Consumption measured as primary energy (PE) in kWh per m² of net floor area (SHON) per year (readings taken in 2004 and 2005)

• Gas (heating): 86 kWhPE/m²/year
• Electricity: 23 kWhPE/m²/year
• TOTAL: 109 kWhPE/m²/year

• Méandre Architecture (in the Seine-Saint-Denis department-France)
• MCI Thermiques (in the Marne department-France)

BCB Tradical^®: contact@weber-tradical.com

Examples of hempcrete homes and buildings

The building that is now home to the tourist office was built at the start of the 16th century in an old quarter of Troyes called Foires de Champagne, which was famous throughout medieval Europe.

The main contractor wanted to restore this building in keeping with traditional architecture, but using modern techniques that have proved their worth over the last 15 years in the town of Troyes, where several buildings have already been restored using Tradical^® Hempcrete.
Claire Perron, the architect in charge of the project for the town council’s Urban Development and Heritage department, is an expert in restoring traditional buildings and offered to use a material that was suitable for half-timbering, but would not compromise its charm.

Hempcrete offered the thermal and vapour regulating properties required for the insulation and it was one of the reasons why the architect chose this material.

Hempcrete inherently rhymes with thermal performance. The tourist office building provides a perfect example of the benefits of hempcrete when you want to save energy and improve thermal performance.

The energy value recorded is barely above 100 kWh per m² per year, making the building eligible for French Bâtiment Basse Consommation Effinergie Rénovation certification. The entire building will be monitored for its hygrothermal performance and comfort using an integrated monitoring system.

This project actually enabled Troyes to win the French regional PREBAT 2011 call for projects, becoming the only town to be awarded a prize for an old building.

Insulating screed made with Tradical Hempcrete

In the basement, Capristo cast an insulating screed in a part of the building that was going to be used for the archives. It was cast in compliance with French professional rules (included at the project design stage). A 25 cm thick drained hardcore layer was laid and a Tradical (BCB) Hempcrete screed, made of Tradical PF 70 + hurds, was cast on top of it.

300 m² of half-timbered Tradical^® Hempcrete walls

Léon Noël, a firm of builders specialised in listed buildings, carried out the hempcrete work involved for the half-timbering and the roof.
The builders sprayed a 30 cm thick insulating wall between the timber framing: Tradical^® PF 70 plus hurds (mix proportions = two bags of Tradical^® PF 70 for one bag of hurds).

300 m² of exterior wall finished with traditional Tradical^® lime render

A complementary material that would respect the vapour permeability of the hempcrete wall was required. The builders therefore applied a two-centimetre thick layer of traditional Tradical^® lime render, with base and brown coats made with Tradical^® PF 70 plus sand, and the finishing coat made with Tradical^® PF 80 plus sand and natural pigments.

Interiors finished with a Tradical^® Hemp Render

Again, with the idea of maintaining the hygrothermal performance of the hempcrete wall, the builders applied a three-centimetre thick layer of hygrothermal lime render, made with Tradical^® PF 80 plus hurds.

340 m² of roof insulated with Tradical^® Hempcrete

The builders mechanically cast the hempcrete to a thickness of 30 cm (mix proportions = one bag of Tradical^® PF 70 for one bag of hurds).

• Net floor area: 712 m²
• Net floor area (SHON) created: 302 m²
• Building height: 14.82 m

• Main contractor: Troyes city council – Building department – Architect, Claire Perron
• Thermal engineering consultants: MCI Thermiques
• Company in charge of demolition, masonry, stone cutting and hempcrete casting: LEON NOEL SAS
• Contractor in charge of structural work and casting the insulating screed in the basement: Entreprise Capristo
• Contractor in charge of the timber framing: Les Charpentiers de Troyes

• Insulation methods: Mechanically projected hempcrete infill for the half-timbering and the roof, and hempcrete projected onto a hardcore layer for the screed.
• Hempcrete project end date: August 2012
• Total surface area of hempcrete: 630 m² with an infill thickness of 30 cm

BCB Tradical^®: contact@weber-tradical.com

More examples about hempcrete houses and buildings

Renovation and conversion

The Ile-de-France regional council awarded this project to architects Belus et Henocq. The architects reinvented the idea of traditional rural architecture, with a daring yet respectful architectural approach to heritage, opening the door to the future for this site which now houses offices, meeting rooms, multi-purpose rooms and a cafeteria.

The main contractor offered a solution consisting of a Tradical^® insulating lime-hemp lining made with Chanvribat^® and coated with a Tradical^® hygrothermal render, and it works excellently here as a high-performance insulation layer. The building benefits from the material’s plasticity in view of the geological constraints imposed by the marl-type soil.

Tradical^® Hempcrete lining and stone walls are a perfect match

The architects decided to keep the large open spaces of the barns (9 m up to the roof ridge and 4.5 m high walls). These volumes required excellent insulation.
The volumetric dimensions are 862 m³ for the cafeteria, 2,329 m³ for the open space in building A, 231 m³ for the music room, 1,009 m³ for the multi-purpose room, and 713 m³ for the dance studio.
BCB’s insulation solution consists of an insulating lining combined with an insulating render.
It was chosen because it has a high thermal performance rating, it is perfect for mineral substrates, it has excellent hygrothermal properties and it can be used on high walls.

Awarded French high energy efficiency (HPE) C certification (ref. -10%)

Tradical Hempcrete lining

• Thickness of 14 to 18 cm. Overall R value of 1.8 m² K/W for the room.
• Surface area of 650 m²
• With the Tradical^® PF70 + Chanvribat^® blend

Tradical^® Hemp Render finish

• Thickness of 3 cm
• Surface area of 650 m²
• With Tradical PF 80 M + hemp

BCB Tradical^®contact@weber-tradical.com:

More examples about hempcrete houses and buildings