What
is a Curtainwall Test?
Energistics was one
of the first firms to perform curtainwall tests. We have probably
performed more of these tests than other laboratory in the country.
There is a wide range in the thermal properties of the glass and
mullions that form a curtainwall. One of the common uses for a curtainwall
test is to insure that the proposed curtainwall is neither under
- or over-engineered for the climate in which it will be built. Therefore,
it is critical to check thermal performance under actual
mockup conditions. As an example, a building in a city with a colder
climate would benefit from a curtainwall system that had better thermal
properties than a city with a warmer climate. The better the insulating
characteristics of the glass and mullions, the easier it is to attain
and hold the temperature set point. Another purpose is to allow the
clients to "feel" what the space will be like when the
heating and air conditioning systems are operating.
How
is a Curtainwall Test Conducted?
In a curtainwall test, we construct both
the curtainwall and a typical office space, taking into account
room size, ceiling height, and the positions and sizes of the
diffusers that will be used to distribute the air. To test the
efficacy of the proposed curtainwall, we set both the airflow
and the temperature to the specified levels and monitor the ability
of the diffusers to keep the room at a specific temperature set
point.
Curtainwall
tests also help us to monitor the flow of air movement as it
exits the specified slots or diffusers. As the air enters the
space, we actually "map" the movement of the air with
smoke generated by a commercial "smoke" machine. As
the smoke disburses, we can videotape its movement.
Successful
Curtianwall Testing
Reference for temperature and airflow
are very individual, and in some cases, regional. In the northern
climates, occupants don't really like to "feel the movement
of the air" in the space. In cities like Houston, the preference
is just the opposite. For these reasons, we insist that the
client actually come to the mockup test and experience the conditions
him - or herself.
The
most common problem we find is that the specified diffusers do
not perform as the client wishes... sometimes "dumping" the air
so it literally hits the occupant in the head; other times stratifying,
coming down in layers so that it is cooler at the floor than
it is higher up. In a recent project we were able to remediate
this problem for a client by recommending and then testing different
diffusers. |
