Wraxall Yard

The stone and brick dairy barns date from the mid-19th century and sit on the edge of Lower Wraxall, adjacent to the Grade I*-listed St Mary's Church. They are arranged around a courtyard extending to the South to create a more open farm yard, flanked by a steel Dutch barn.

We developed a new environmental and building services strategy for the derelict stone and brick barns.

As much as possible of the original building fabric was retained and thermally upgraded. The existing stone walls are insulated with vapour permeable cork insulation. Roofs are generously lined with woodfibre to provide the lowest thermal diffusivity and hence a slower reaction time.

Existing openings have been reused in collaboration with new opening rooflights to enable cross ventilation through all buildings and generous daylight within all primary rooms.

The site water supply is derived from a local spring at a rate of 1m³/hour. A large underground collection tank provides a buffer to on site water treatment and the potable water supplies. The storage and distribution are designed for dual purpose and feed both domestic appliances and fast acting sprinkler heads within each building.

All foul water is treated on site through a bio-digester. The treated water and surface water are discharged to the nearby River Frome.

A ground source heat pump system was initially proposed as the primary heat source, but it was eventually decided to use biomass wood chips given the availability of thinnings from the local forest.

The site can accommodate wood chip deliveries from a 2-axle tipper trailer and part of the Dutch Barn has been designed to store up to 60m³ of wood chips in a dry environment. A 20m3 secure wood chip store with rotating blade agitator feeds a 50kW ETA biomass boiler.

Wood chip is transferred between stores by a tractor with a grain bucket.

Primary buried supplies for heating, water, power and data are routed to all buildings within the site from common plantrooms. Each cottage has a utility cupboard acting as a distribution node to receive the incoming services and then distribute heat, hot and cold water, power and data throughout.

Careful consideration was given to the planning of the equipment to ensure electrical consumer units, heating & hot water controllers are positioned to be wheelchair accessible.

The Barrier-free design includes switches and sockets at accessible heights, fully integrated motorised hoists for the mobility impaired, and vibrating fire alarms for the deaf.

Water and drainage connections work with motorised rise and fall worktops in each kitchen for ease of cooking using a wheelchair.

The refurbished building achieved an A rating in the post construction energy performance certification.