Timberframe replacement home, Ottershaw

Overlooking open farmland to the south, this backland site is accessed down a narrow driveway between a pair of ordinary looking detached houses in Ottershaw, Surrey.

Replacing an existing chalet bungalow with a full two storey house while still satisfying the planners was always going to be a challenge and several different design options were explored for the roof form.

The final approved scheme, due for completion on site in Spring 2018, included a shallow monopitch roof to create full height first floor spaces while maintaining a lower eaves to the north front elevation.

The main timberframe and foundations were build by MBC Timberframe who specialise in Passivhaus buildings. They completed the insulated raft foundation which laps with the external wall insulation within their twin-wall with minimal thermal bridging. U-Values down at 0.12 and with guaranteed air-permeability rates below 0.6 air changes per hour help drive energy costs down.

A standing seam zinc roof with pre-weathered ash Thermowood cladding over a self-coloured acrylic white render with light grey aluminium windows complete the palette of materials.