The Barrel Store Youth Hostel

This is the first Passivhaus certified youth hostel in the country created by the conversion of a large former barrel store in an arts centre in Cirencester.

As well as being first, the Passivhaus Certified project will also be the largest building in Gloucestershire with this certification. The hostel will play host to parties of school children as well as providing accommodation for those attending courses and workshops run by the building owner, New Brewery Arts.

For the design team, the Youth Hostel Project design has presented a few challenges compared to other Passivhaus structures, simply because of the scale of the project and the number of rooms requiring water supply and ventilation. Additionally the original design had to be pared back to meet lower than expected levels of funding, but the finished product is an impressive, Passivhaus-certified building which uses innovative approaches and may well form the blueprint of other, similar projects.

Toby Cambray, Director, Greengauge Building Energy Consultants, who are responsible for the Pasivhaus Assessment of The Youth Hostel, says “The Youth Hostel is certified under the Enerphit scheme. The particularly challenging aspects of this project have been the design of the wall and roof insulation. Budgetary constraints meant a wholesale replacement of the roof would not be possible, and the new, thicker insulation had to be fitted internally, complicated by the need to upgrade some of the structural timbers. The wall insulation system will achieve a U-value of around 0.2 W/m2.K The roof and floors achieve around 0.1 W/m2.K, and windows at 1.0 W/m2.K (centre pane 0.52 W/m2.K). The ventilation system will recover 80% of the heat from the stale exhaust air into the fresh supply air.

Speaking of the project Ali Russell, Centre Director for New Brewery Arts says “I originally pitched the idea of the Youth Hostel to the Trustees as a way of creating a sustainable future. It has been funded mainly through grants from The Arts Councils and Winstone Trust, as well as through private donation. We’re really excited to see the project come to fruition and know that it will be a great addition to Cirencester and the County. The Passivhaus status will be a bonus and hopefully the success of our project will be a pilot for more projects like this in the future.”

Technical details for the Youth Hostel build include:

• 48 bedspaces
• It has been developed in close consultation with the YHA and includes maximum privacy for shared accommodation rooms and minimal sound transmission between bedrooms.
• It will adopt the Passivhaus principles of high levels of insulation, air tightness and controlled ventilation using mechanical ventilation systems with heat recovery. The building also features a “microbore” hot water supply pipework to minimise heat loss from the hot water system.
• Minimal sound transmission between bedrooms thanks to consultation with Ion Acoustics
• The proportion of rooms requiring water supply and ventilation was very high and this resulted in a more complex servicing installation than is normally found in Passive House projects
• The construction will be within the existing envelope of the stone building with slate roof; a highly insulated and air tight timber structure will be inserted with accommodation at ground and first floor levels and the Plant in the roof void
• The external walls are being insulated from the inside with a build-up of wood fibre insulation products, which allow the building to “breathe” and thus reduce the possibility of the build-up of water vapour and condensation. The existing roof coverings are being retained, and rigid insulation boards are being applied between and under the existing rafters to meet the required levels. The existing lower ground floor is being filled and the new ground floor slab will “float” on a thicklayer of insulation board which will be turned up at the edge of the perimeter of the slab to remove “cold bridges”.
• The finishes use natural finishes where the budget permits – Hardwood (a mixture of oak and ash) and linoleum flooring, and waxed or stained timber internal joinery
• The internal layout is of a generous entrance hall with a top lit winding oak staircase lined with ash boarding (the barrel…) with a common lounge and kitchen to one side at ground floor level, and to the other laundry, linen store, disabled persons adapted bedroom and shower room and other bedrooms with 30 bedspaces at first floor level
• Initially the first designs included a front projection for hotel-styling, but this was later revised as the initial fundraising fell short of target.