Surface Design Awards – Complete

• HOUSING - INTERIOR 
  Buildings such as houses, flats and apartments that are used for sheltering people. These could be either part of the private or public sector and could be individual dwellings or multi-dwelling developments. Social rented, affordable rented and intermediate housing, provided to specified eligible households whose needs are not met by the market are included.

This extension and remodelling project breathes new life into a large Arts and Crafts house, harmonising disparate elements and adding bright, hardworking spaces.

The original building was run down, with mismatched extensions from different eras. Convoluted routes through the ground floor and the lack of connection between the entrance and the garden made it feel disjointed.

The clients - a couple who relocated from the city in the search of countryside on their doorstep and more space for visiting family and friends – wanted to improve the flow of the house and unlock space for hobbies and entertaining.

Inserting a double height central volume into a previously unused external gap was a key design move, creating a new ‘heart of the home’ which links all the main living areas and gives unexpected views across and through different levels and spaces in the house, as well as to the outside. The design unifies the ground floor while celebrating the house’s original Arts and Crafts spirit.

The scheme delivers a new kitchen and home office, a utility room with direct access to the outside to minimise muddy boot and paw prints, and a training room with ensuite shower – perfect for an enthusiastic cyclist.

A large side extension with mirrored double pitched forms to front and back houses the kitchen and training room, linked by a central utility and shower to maximise functionality.

The exposed timber roof structure, made from sustainable douglas fir, brings rhythm to the spaces. A family of solid oak-framed windows and large glazed doors fill the ground floor with light and pull together the different areas.

Materials have been chosen to blur the boundaries between the different sections and periods of the house – including solid stone and oak for the floors inside and bricks and clay tiles externally which reference the house’s period architecture. The breathable lime plaster and wood fibre insulation specified are sustainable materials which also improve the internal environment.

Completed Jan 2022, project cost: £292,500 ex vat

Oak has been used across the windows and doors, stairs, flooring and custom joinery. This traditional native timber was popular with Arts and Crafts pioneers, referencing the building’s heritage. Prized for its strength and warm tone, oak also ages beautifully.

Prime visual grade solid douglas fir used for the roof structure has been hand painted so that the natural grain of the timber can still be seen.

St Astier Ecomortar R50, a Natural Hydraulic Lime Eco pre mixed renovation plaster. This readily available material is a relatively affordable and simple to apply alternative to specialist plasters that can still be used to achieve truly beautiful results. The textured finish brings a warmth to the space and catches the changing light throughout the day

The stone used for the kitchen floor references traditional flagstones and the hand built and painted kitchen units are made of tulipwood.

The use of low carbon materials, prioritising natural light and ventilation and improving thermal performance were the main sustainability drivers for the project.

Douglas Fir has a very low carbon footprint in sourcing and low embodied energy in processing. It is sourced from well managed forests in Wales and is strong, durable and lighter than hardwood alternatives – minimising transportation loads. This timber has a reliable supply chain, it is fit for purpose with a single conversion process and is low maintenance in situ – all of these factors result in it being carbon negative overall. Using Douglas fir for the exposed timber structure also reduced the amount of steel and concrete required.

Pavatex wood fibre insulation was used in the building envelope. It is produced from 95% natural and sustainable building materials, manufactured from waste sawmill wood shavings, which locks up more carbon that is required to produce and transport it.

The use of wood fibre insulation lowers energy requirements and reduces emissions of CO2. Its thermal mass keeps the property warm in colder months and cooler in the summer than the equivalent PIR insulation. are reduced and carbon is bound by the structural use of wood. The boards are free from harmful substances and, thanks to their vapour permeability, enable healthy and pleasant rooms as well as secure constructions. At the end of their lifetime, wood fibre insulating materials can be composted or thermally utilised in other applications.

The ceilings of the extensions were lined with natural hydraulic lime plaster which is produced with lower energy than cementitious mixes and re-absorbs CO2 during the production process. It continues to recarbonate CO2 over its in-use phase, creating a complete life cycled, closed-loop process, resulting in negative carbon emissions. This breathable plaster helps regulate internal humidity as well as bringing warmth and tactility to the space.

The use of timber framed windows and doors contributed to the reduction of embodied carbon, having – on average – around half the lifetime carbon footprint of metal-framed glazing.

The natural stone floor was selected for its sustainable credentials – a recent comparison of floor coverings showed that those produced from natural stone cause a significantly lower environmental impact in their production, installation, and use than common alternatives.

The expansive glazing and rooflights maximise natural light entering the home. By incorporating opening rooflights at high level, stack ventilation is encouraged enabling a comfortable internal temperature to be maintained. All if the existing windows in the property were replaced with high quality double glazed units, dramatically improving the building’s overall thermal performance.

The project had a tight budget and the architects worked hard to find a local contractor who they could collaborate with to achieve a low cost of £1662/m2. The scheme was delivered under the challenges of negotiating post-Brexit supply chains which delayed the arrival of the doors and windows by 3 months, necessitating a re-configuration of the schedule of works.