Conveniently located in the heart of Finchley in North London, Church Crescent is a residential street of large semi-detached family homes. A recent project, executed by Evonort Architects for a private client had three particular goals; a rear extension to create an informal dining area bridging the half storey change in level between the kitchen and garden terrace; rearranging the first floor bedrooms to form a master bedroom suite; and excavating part of the basement to increase headroom and create an additional bedroom and shower.
Every extension project is unique and Evonort Architects worked closely with the client to create a modern and bespoke extension that would sensitively integrate with the brick house and mature garden. Evonort sought to specify just one material that would be suitable for both the interior joinery and the exterior of the extension. After extensive research into sourcing a suitable type of oak, American white oak was the timber of choice. For the exterior walls, the unfinished creamy light brown tones of American white oak which will weather naturally and require little maintenance for the life of the building, appealed to both the client and architect. In contrast to the natural finish cladding, pre-finished engineered white oak boards were suitable for the interior floor, steps and joinery in the extended dining area as it is a hard and heavy wood with a medium bending quality and visually appealing. A number of timber suppliers were contacted in order to discuss at length their requirements and criteria for the timber. According to Adam Howard from Evonort, “We wanted an oak that was sustainable, within budget, durable for external use without sealing or finishing, and available in our specified size of 32mm x 32mm. American white oak was the perfect solution”.
The objective was to create a contemporary rear extension with substantial glazing to maintain maximum daylight in the existing kitchen. Square sections of natural American white oak were used to clad the extension walls and roof, surrounding the glazed sliding doors and large roof light. The solid white oak rain screen cladding helped to achieve a detailed bespoke and contemporary aesthetic manner following the slope of the roof. Carrying the cladding over the roof with flush detailing to the roof-light helped to enhance the building when viewed at any angle. This gave the extension a sharp and dynamic appeal whilst sensitively integrating the extension with the brick house and mature garden.
A system of double battens allowed for a construction method to avoid visible fixings. By creating angled notches in the secondary battens to the front face of the extension, the square section cladding was also fixed at the angle of the roof, creating an interesting junction with the side elevation cladding. 10mm gaps between 40mm oak enable ventilation behind the cladding.
The finished result was hugely satisfactory to both the client and architect. Evonort worked to a specific brief from the client but were able to deliver a beautiful white oak cladded exterior displaying the luminous dining area extension, creating a warmth and brightness to Church Crescent.
Species: American white oak
Photographer: Janie Airey
More information on American white oak
Botanical name: Quercus spp.
American white oak has a creamy coloured sapwood and a light to dark brown heartwood. White oak is mostly straight grained with a medium to coarse texture, with longer rays than red oak, producing a distinctive and attractive grain pattern.
American white oak is widely available and is a popular choice in export markets around the world for many furniture, flooring and joinery manufacturers due to its colour consistency and the high volume of square edged lumber production, and veneer availability. The wood is hard and heavy, with medium bending and crushing strength. It is low in stiffness, but very good in steam bending.
To be used externally without preservation a timber has to have a minimum durability rating of Class 3, moderately durable. American white oak meets these requirements. As with all timber, if sapwood is present then preservative treatment will be required.
AHEC produces a full range of technical publications which are available free of charge by visiting www.americanhardwood.org or by faxing (44) 20 7626 4222