James Alder Architects has completed a timber-framed residential extension in Crystal Palace, south London, designed to support gardening, cycling and family life. Called the Tabberner Cook House extension, the 57-square-metre wraparound structure introduces a potting shed, bike workshop and a new family kitchen, blending functionality with a calm, nature-oriented aesthetic.
A Multi-Functional Extension
Extending across the rear and side of the existing home, the addition goes beyond typical London refurbishments. The layout is tailored for a family of four seeking dedicated hobby spaces, seamless indoorโoutdoor flow and improved ground-floor storage. The extensionโs design prioritises practicality while maintaining visual warmth.
Operational Details: Potting Shed, Workshop and Family Kitchen
A standout feature is the indoor potting shed, equipped with generous plant-nurturing surfaces and storage. An oak-framed greenhouse cabinet uniquely links the potting area with the kitchen, enabling easy access from both rooms.
Additional integrated planters frame the kitchen edges and cascade down a new patio terrace.
Behind the potting room, a bicycle workshop offers space for storage and maintenance, supported by a WC, pantry and utility room. A secondary entrance allows direct access to these hobby-focused spaces.
Design and Materiality
To balance durability with a light aesthetic, the architects selected pale, robust materials suitable for gardening and workshop activities. The extension is characterised by:
- White brickwork for interior and exterior walls
- A whitened glulam timber waffle-slab ceiling with skylights
- On-site fabricated zinc cladding for upper walls and roof
- Aluminium-framed glazing wrapping around the elevations
These choices contrast with the main houseโs dark brick and slate roof, creating a brighter, contemporary expression.
Economic & Livability Impact
The extension not only boosts the propertyโs functional value but also enhances daily living by integrating dedicated hobby spacesโreducing clutter and improving workflow for gardening and bike maintenance. The enriched connection with the garden supports healthier, nature-oriented routines for the family.
Strategic Significance
This project exemplifies a growing trend in London architecture: designing multi-purpose residential extensions that accommodate modern lifestyles. By addressing hobby needs alongside family living, the Tabberner Cook House sets a thoughtful precedent for future domestic renovations.

Share your work with Architecture Pulse. Upload your PDF below.