kingsknowe // retrofit
A deep retrofit and extension of an existing tired 1920’s house located in south-west Edinburgh
The existing dwelling had been extended poorly; excessive circulation and sub-standard construction culminated in this once attractive, robust building being blemished by alterations. The initial project brief was to reorganize the layout and thermally upgrade the fabric.
Early design discussions were borne out of our client’s desire to capture the essence of previous lives in a more temperate climate: maximising a connection to the external environment, living in well-lit and harmonious spaces, and creating safe and healthy family orientated places that they could all enjoy.
The contemporary and energy efficient replacement extension, in tandem with the conversion of the central portion of loft space, creates designated areas for family activities as well as home working.
The climate emergency is about more than energy reduction: decarbonisation and ecological regeneration are imperative for a truly sustainable future. Our whole-building retrofit measures were driven by a multi-fold approach, in which the component parts operate synergistically.
Energy reduction through additional insulation and controlled air leakage, with consequential reduction in unintended heat loss, combine with a move away from a gas energy supply to a building powered by LZCGT’s: a holistic approach towards decarbonising the retained and upgraded building.
The front elevation has a modest appearance that merely hints at the changes that have taken place behind: a contemporary canopy between two existing bedroom projections creates a practical covered space that signifies the entrance; a glimpse of some renewables on the refurbished slate roof signal the use of the high performing building technologies.
The exterior of the extension is defined by the tapered edged, untreated timber clad ‘lens’ which addresses the rear garden and open landscape beyond. The existing slate roof was refurbished with all usable slates salvaged and re-fitted around the new integrated PV array. Zinc cladding to the extension sides and dormers also speaks to the durability and re-use or recyclability potential of many of the chosen materials.
Natural bio-based insulation materials were selected for their reduced embodied carbon as well as vapour open moisture management properties.
The extension roof will feature an extensive sedum blanket to promote biodiversity and ‘give back’ an area of elevated garden; seen by the occupants from the dormers of the newly converted roof space and enjoyed by insects and birds alike. High performance glazing facing the garden combines with rooflights overhead to flood the new family space with light, providing a fresh, contemporary space at the center of the home.
This axonometric diagram explains the key retrofit steps that we undertook to ensure the longevity and durability of this home.
In-use data from the owner confirms an energy reduction of c.73% compared to the base-case of the dwelling prior to the works.
The completed house has been restored: it is now a demonstrator that sits comfortably within the suburban context and discreetly represents the best methods for de-carbonising and regenerating an existing building.
Structural Engineer // Form Structural Engineers
Photography // David Barbour photography