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the combined attributes. For instance, proper combinations of passive design techniques
for reduction of energy demand and active renewable techniques for power generation
are of important in enhancement of values rather than costs. Accordingly, this study
focuses initially on examining some passive design techniques selected in view of the
Government’s Standard Assessment Procedure (SAP) for Energy rating of Dwellings,
which has been applied for issuing Energy Performance Certificates in the UK. Moreover,
active mechanical devices such as heating systems and renewable energy technologies
are also taken into account for further comparative analysis of design components.
Based on the SAP calculations, an analysis matrix that aims to combine the design
components selected will be shaped so as to examine the cost effectiveness. The
assessment tool will be unveiled after the list of design options (i.e. components and
approaches) relevant to this study is identified below.
Orientation of building unit
: The orientation of a housing unit can be considered as
critical for optimal use of solar gains for heating and lighting as well as power generation.
Some projects do not allow stakeholders to determine the orientation due to the site
constraints. Also, the relationship of a building to the sun and prevailing winds may need
to be taken into account while the site and building configurations are planned. The
building facades should be oriented in a way that helps maximise solar heat gain in cool
and cold climates, yet it needs to be designed to reduce glare and overheating. The
optimal use of daylight minimises the need of artificial lighting during the daytime. It is
desirable that the zoning and placement of internal spaces should be planned with due
consideration of the above aspects.
Built form
: The type of built form, such as attached, semi-detached, and detached
housing, as well as flat multi-floor residential dwelling unit, needs to be identified for the
simulation of energy demand. There is a clear relationship between the exposed area of
building envelope and the associated heat loss. However, due to the site setting applied
to ZEMCH 109, only end-terraced option was considered for further assessment in this
study.
Sheltering sides
: The amount of buildings’ heat loss is partially related to the level of
wind protection of building envelope, which could be affected by trees and buildings
surrounding the house in question. According to BRE 2009, “a side of a building is
sheltered if there are adjacent buildings or tree-height hedges which effectively obstruct
the wind on that side of the building” (BRE 2009). The sheltering depends on the height
of obstacles surrounding the house in question, distance between obstacles and the
house and the width of obstacles.
Draught lobby
: The minimisation of ventilation heat loss is one of challenges and a
main entrance may need to be protected by the placement of a drought lobby which
consists of two doors that form a lobby. To satisfy the function, the floor area of at least
2m² is requited (BRE 2009). The Draught lobby helps prevent or minimise the entry of
direct air into the house every time the external door is used.
Location and size of lounge
: To maintain thermal comfort, the temperature of a
lounge/living room is usually estimated at 21
°
C in view of SAP calculation. On the other
hand, 18
°
C setting is applied to the rest of the house. The lounge can be placed on the
upper floor to reduce or minimise heat loss while the size also affects energy demand for
space heating.
Size of opening
: The size of windows correlates with the amount of solar gain and
natural light, as well as heat loss. Moreover, cross ventilation can also be secured by
