Pocket House, London

Introduction

Pocket House is an award-winning family house, distinguished by its character, the quality of its detailing – much of it in timber – and by the skill with which the architect has made use of a dauntingly restricted site. It is the first building completed by Tikari Works, a young practice established in 2014 by Nicola and Ty Tikari, and it is also their family home. They were not only client and architect but also acted as main contractor, directly employing a team of craftsmen and subcontractors for the building works.

The site itself, in a residential street in London, was only 80 square metres in plan and was additionally limited by planning restrictions, existing building lines and by a need to maintain a neighbour’s privacy, resulting in a ground footprint of only 35 square metres. To avoid overlooking neighbours at the rear and sides, all windows had to face west towards the street.

The challenge for the architects was to create a house which would not feel compromised by these limitations. The solution was to locate part of the house below ground in a basement, with a large courtyard cut into the corner of the basement plan to bring natural light into the lower rooms.

The ground and first floors of the house step back from the street to align with neighbouring building lines and at the rear the first floor is also set back to limit impact to adjoining gardens. To make most effective use of this arrangement, the more private spaces – two bedrooms and bathroom – are placed below ground and orientated around the sunken courtyard. A timber ‘pod’ placed in the darkest corner of this floor contains a family bathroom. The thick 'poche’ walls of the pod create spaces for desks and storage.

The kitchen and dining areas are at ground level and are separated from the entrance sequence to the house by another timber ‘pod’ which contains a WC, coat cupboard and kitchen storage. A timber staircase at the rear of the house connects the floors and leads to an open plan living space on the first floor.

The unique character and quality of the house is imparted by the use of timber, both externally and internally. Facing the street, the main elevation is clad with a screen of vertical cedar slats. Internal surfaces are lined with spruce plywood panels, conveying a warm and hand crafted feel.

The external timber cladding and screen

On the main elevation a screen of vertical western red cedar slats extends from basement to roof, harmonising the façade into a sculptural ‘whole’. It makes reference to local timber garages and garden sheds, helping to contextualise the building.

The screen acts as external cladding to solid walls and also covers parts of the floor to ceiling glazing on the ground and first floor, where it helps to mitigate the conflicting requirements of daylight versus privacy as well as keeping the western sun at bay.

As a screen to the glazing, the vertical slats of 32 x 38mm western red cedar are screwed 30mm apart with stainless steel screws to a sub-frame of horizontal and diagonal bracing of 45 x 45mm cedar battens, sloped at the top to throw off rainwater.

In front of the solid walls, the vertical cedar slats act as a rainscreen and are lined with vertical 18mm cedar boards with open joints, on a horizontal sub-frame fixed back to sarking board which in turn is fixed to the timber stud wall. Similar vertical cedar slats are used in a simplified form as balustrading to the basement and to the entrance walkway.

The slats are finished with a white Osmo Natural Oil Woodstain.

The rear and side walls of the house are of insulated brickwork, fair-faced on the inside, and the ground floor is a cast in-situ concrete slab.

The internal use of timber

Of the inside, the architect explains: ‘To enhance the sense of space, perspectives are carefully curated as you move through the house, focusing views into other rooms or outside to planted areas. Oversized doors and folding walls further play with your expectations and sense of space, offering a more generous experience. Punched windows are rejected in favour of full height glazing, creating an arrangement of solid and void which helps create a unity between the limited outdoor space and internal spaces.’

The Douglas fir joists which support the ground and first floor ceilings are exposed and lined with 18mm South American pine plywood soffits. The internal walls and partitions, together with the basement and first floor ‘pod’ walls and storage units, are lined with exposed 12mm spruce veneered plywood panels. The wall panels rise to the undersides of the Douglas fir joists, reducing the need for horizontal joints.

Internal doors were purpose-made to be taller than standard sizes, so that the frames align with the underside of the joists; several are also wider than standard sizes and fold back into purpose-made wall niches.

The warm and pleasant aspect of the first floor living room is enhanced with a rear wall of Douglas fir bookcases with cupboards below, and a Douglas fir boarded timber floor. Like other rooms in the house, the double-glazed windows are storey height, and are made of Douglas fir.

A solid yellow pine staircase runs along the rear wall of fairfaced brickwork, with a 2 x 18mm structural balustrade of decorative South American pine plywood sheets bonded together with adhesive. The internal timber surfaces were finished with Osmo Polyx Oil.

The structure

Richard Watkinson, structural engineer and director, Built Engineers Ltd, describes the structure:

‘The predominantly visible structural timber of Pocket House required careful design integration with the masonry and steel elements to achieve the architect’s clean visual detailing.

The stepping external walls and the structural voids to rooflights and stairs make use of hidden steel framing elements to maintain stability of the external envelope. The trimming structure to the main rooflights and stairs utilised steel T-sections flitched between pairs of joinery grade Douglas fir joists, designed to allow a consistent member size across the visible floor and roof soffits.

The high standard of workmanship was achieved by pre-fabricating the floor and roof in cassette panels which were lifted into place on site with all visible fixings plugged. The exposed Douglas fir joisting is sheathed with Douglas fir plywood to form structural diaphragms at floor and roof levels; we utilised a mix of traditional half-lap joints and modern screw and dowel fixings to achieve a clean interface with brick and timber walls.

The bespoke staircase was given our usual scrutiny, with detailed hidden connections between elements as well as consideration of practical installation on site. A perimeter face- fixed plywood stringer to the outer edge is detailed with spacers to achieve a shadow gap to the exposed brick. At the inner stair edge the laminated plywood balustrade forms a stiff beam element in combination with a localised steel stringer to achieve a rigid connection with the supporting flitch beam at first floor level. The main flight has open risers, allowing light to permeate, and the laminated plywood treads span between the plywood stringers with housing joints and hidden screw fixings.’

Awards

2019 RIBA Regional London Award

2019 RIBA House of the year shortlist

2019 Wood Awards: Private sector, Highly commended

2019 Stephen Lawrence Award shortlist with special mention awarded by jury

Completion Date:

May 2018

Building Type:

Private house

Location:

East Dulwich, London

Architect & Client:

Tikari Works

Structural Engineer:

Built Engineers

Main Contractor:

Tikari Works

M&E Consultants:

SGA Consulting

Joinery:

Tikari Ltd

Timber Supplier:

Whittens Timber, Silva Timber, Specialised Panel Products

Kitchen Manufacturer:

Uncommon Projects

Timber Elements:

cladding, floor and roof joists, staircase, internal wall panels

Timber Species:

PEFC-certified Canadian western red cedar,
PEFC-certified North American Douglas fir, PEFC-certified Finnish spruce

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