We control direct UV radiation
by placing a barrier so that it intercepts the sun’s rays,
thus creating ‘shade’. The barrier could be built or natural
(such as trees and other vegetation.)
The barrier must
be the right size and be located in the right place. It must
allow for daily and seasonal shade movement.
The
quality of the shade created depends on the properties of the
barrier:
'solid' or opaque barriers (such as metal roofing,
structural PVC
fabric and dense foliage) will create dense shade and
provide good
protection from UV radiation
'open' or transparent barriers (such as natural glass,
open
lattice or sparse foliage) will generally create light
shade with limited protection - polycarbonate and treated
glass are exceptions to this, as they can provide high
levels of protection from UV
radiation.
Built shade provides
greater design possibilities, while natural
shade can include the cooling effect of trees and
enhance the aesthetic qualities of a site. In many situations
a combination of built and natural components
will be best.
In WebShade, ShadeDesign
provides design guidelines for creating effective shade using
built and natural shade systems and profiles the advantages
and disadvantages of each.
Shade +
comfort Shade should be designed to provide
comfort for outdoor spaces as well as protection from UV
radiation. To do this, an understanding of the local climate
of the site is necessary.
In WebShade, ShadeCalendar
lets you tell the type of protective shade (warm or cool)
required at your location throughout the year.
Cool shade - Providing shade in summer
that protects against UV radiation and provides a cool
environment is a high priority in most locations. Cool shade
should minimise UV radiation levels and reduce heat and
light. Trees and materials which significantly exclude heat
and light, as well as UV radiation, are suitable.
Warm shade - Many locations have high
UV radiation levels in autumn and spring and so providing
protective shade that is comfortable when the weather is
cool is a priority. Warm shade should minimise UV radiation
levels, while allowing heat and light to be transmitted –
this can be achieved by using materials such as
polycarbonate and treated glass.