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Often referred to as building physics in Europe.

Definition:

Building science is the systematic study of the physical performance ofbuildings under natural conditions.

It is an applied science that draws on the more fundamental sciences ofphysics, chemistry, and biology.

Building science provides the base of knowledge and understandingthat permits designers, builders, product manufacturers, and building

code officials to deliver buildings that are durable, useful, sturdy,healthful, and comfortable.

William Rose, Water in Buildings

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One way of classifying the major systems

of buildings is by their function:

The building envelope or enclosure is an assembly of componentswhich separates two different environments

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At times this assembly is best characterized byits ability to resist forces, stresses or loads

solar

radiation

precipitation

exterior air

temperature

soil

temperature

interior air

temperature

soil moisture

level

exterior air

moisture level

interior airmoisture level

exterior air pressure &

movement

interior air pressure &

movement

occupant

activity level

occupant count

building thermal

mass

exterior noise

interior noise

At other times it is better characterized by its ability to controlthe movement of energy and matter, more like a filter.

heattemperature differences

liquid watermomentum, air pressure

differences, gravity, capillarity

air

air pressure differences

soundsound level differences

radiationelectromagnetic energy

water vapourvapour pressure differences

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foundations

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exterior walls &

windows

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floors over basement

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floors over c rawlspace

The various elements of thebuilding enclosure must forma continuous and closedpath

separating interior fromexterior space

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Performance:

overall technical performance of the assembly, identification & functionof each individual component (some perform multiple functions)

Assembly: relationship of components to one anot her & the sequence of their

assembly within the construction, attachment methods, trades involved,

tolerance for movement

Durability:anticipated functional lifetime of each element, maintenance

requirements, potential for replacement of the various components

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