Contemporary Design in Detail: Sustainable Environments

112 Sustainable Environments

Above Windows on the north, east, and west

sides are modestly sized to provide suffi cient

light and views but prevent heat loss.  e wall

construction consists of plywood fl oor joists

run vertically to a height of 25 feet (7.6 meters)

to form a hybrid balloon-framed curtain wall; it

maintains an insulation value of R40 through-

out because the fl oors do not penetrate the

walls but are supported by a post-and-beam

structure within.  e thick walls, fi lled with

cellulose insulation, are clad with a prefi nished

birch plywood rainscreen.

roof

desk

sleeping

bathroom

open to below

solar h.w. panel

outdoor deck

below

113

Alternative Energy Sources

Above Left Windows are triple glazed with a

low-e coating and gas fi ll to admit daylight and

refl ect solar radiation as part of the house’s

“mass under glass” system.  e parallam post-

and-beam frame rests on metal columns just

inside the building envelope.

Above  e concrete fl oors store heat from

sunlight coming through the large south

window and release it at night. On colder and

overcast days, the radiant in-fl oor heating sys-

tem warms the house. During the winter, the

utility service (from which the owners have

elected to buy renewable power only) supplies

just 8 percent of the house’s energy needs; the

rest is generated by the house itself.

114 Sustainable Environments

Bill Dunster Architects,

Beddington Zero Energy Development

(BedZED), Hackbridge, Sutton,

United Kingdom

BedZED launches sustainable lifestyles and

building systems at the scale of the housing

estate.  e architect’s mandate is to reduce

the average household’s yearly carbon emis-

sions output (typically occurring through

energy use, vehicular use, and food sourcing)

and thus its ecological footprint.  e design

retains the qualities of a garden village, while

establishing suffi cient density for a thriving

sustainable community—a model that could

greatly reduce urban sprawl and increase the

quality of life.  is development in a south

London borough, which includes a mix of

eighty-two housing units, workspaces, an of-

fi ce park, and shared leisure and sports facili-

ties, introduces the idea of “solar urbanism”

to the design of the terraced row house.

115

Above Wind scoops with colorful vanes

capture the breeze for the wind-driven

ventilation stacks.  e heat recovery system

preheats incoming fresh air throughout the

buildings using heat from outgoing stale air.

 e system omits a fan-assisted mechanical

system, which would increase effi ciency but

carbon emissions as well.  e passive ventila-

tion system is one of the features of the ZED

in a Box standard housing type (based on the

BedZED model) that the fi rm is selling as a

carbon-neutral housing kit to introduce sus-

tainability to the construction and develop-

ment industry.

Left A section through the three rows of

terraced houses reveals dwellings of diff erent

sizes, ranging from a studio fl at to a three-

bedroom maisonette, as well as live/work

units to discourage vehicular use. All of the

residences have access to either sunspaces or

an outdoor garden. Circulation through the

complex includes both a narrow mews road

and a pedestrian walk.

land garden

green roof

bridge to skygarden

skygarden skygarden skygarden

windcourt

pedestrian walk

sunspace workspace in shade zone

rainwater store

mews road

live/work unit

sunspace

Alternative Energy Sources

116 Sustainable Environments

Right  e development makes the most of

passive design strategies that greatly decrease

the overall demand for heat, enabling the

entire community to meet its energy needs

through renewable sources alone. A large

glazed façade runs along the south side of the

three rows of homes, warming the sunspaces

within, which have fl oors and walls of high

thermal mass.  e superinsulated triple-

glazed windows provide abundant natural

light, and in the evening, the interiors are

illuminated with energy-effi cient artifi cial

lighting. Other passive measures, such as

natural stack ventilation and energy-effi cient

appliances, contribute as well.

Opposite All photovoltaic panels are inte-

grated into the glazing system on the south

façades and terrace roofs. Laminated be-

tween glass, they appear as a seamless part of

the design. Suffi cient solar energy is generat-

ed throughout the development to run forty

small electric vehicles intended for carpool-

ing. A power plant on the site provides other

heating and power needs and is fueled by 850

metric tons (937 tons) of woodchip per year.

 e woodchip is sourced from a regional

urban tree station, which collects tree waste

from two south metropolitan boroughs, con-

verting to fuel a valuable resource that would

otherwise be sent to landfi lls.