Customer Advice Guide
Condensation on Penjerex insulation film
WHAT IS CONDENSATION?
Cold object + Warm Moist air = Condensation
It is quite likely you already know what
condensation is. Getting up in the
morning, you may have seen the water
droplets covering the inside of your
windows.
Although windows may seem like the
culprit, they are actually not the cause of
condensation.
Condensation is due to you and your family's activity within your home. Our activities and our every breath
when sleeping or awake, puts moisture into the air. Water vapour can come from using water, such as when
cooking, showering and growing indoor plants. Use of clothes dryers and some gas heaters can create a
significant amount of moisture in the air inside our homes.
When the indoor temperature cools down the air cannot hold as much water vapour. The result is that the
water vapour condenses as a liquid becoming visible particularly on cold non-absorbent surfaces such as
windows. Unseen moisture penetrates your carpets, fabrics and any other absorbent surface often making
them feel cold and damp.
Even your geographical location and climate can have an effect on condensation. New Zealand humidity
levels vary across the country.
Thermafilm Customer Advice - Penjerex Condensation
Does Penjerex increase or decrease window condensation?
The volume of water on windows with Penjerex applied is 5 times less than compared to standard glass in
laboratory testing.
Penjerex actually causes smaller droplets of water which evaporate more easily. Due to Penjerex absorbing
more of the solar energy than clear glass and that it creates less total volume of condensation and the
droplets are smaller, it can increase the rate at which condensation evaporates.
Condensation generally forms overnight as the moisture in the air and the temperature outside drops. Once
the day’s sunlight and heat increases temperature of glass most condensation disappears and with Penjerex
this process is accelerated so that water droplets evaporate quicker.
Test Conditions
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test conditions
size of glass
glass type
test time
25℃, 70%RH
width 160mm, height 220mm
Float glass 3mm
8 hours
Thermafilm Customer Advice - Penjerex Condensation
Penjerex Condensation volume test result
Condensation
Without Penjerex
2.8 g
Condensation
With Penjerex
5 hours
0.5 g
5 x less
condensation
Thermafilm Customer Advice - Penjerex Condensation
What is the visual effect of Penjerex to condensation?
Penjerex will decrease the volume of condensation but because smaller droplets are formed on the glass and
as the glass is better insulated than standard glass the visual affect is that you are more likely to notice the
moisture as a mist on your windows. In some situations, Penjerex can cause a condensation mist to form on
the Penjerex film sooner than it would on glass as less heat energy is transmitted through glass with Penjerex
causing the glass temperature to drop slightly with Penjerex applied.
How does condensation affect the performance of
Penjerex?
While condensation is present on your windows, Penjerex performance can decrease up to 54%. Thermal
performance of Penjerex will return to 100% as soon as condensation is no longer presentation. Due reasons
mentioned, Penjerex can increase the rate at which condensation evaporates reducing to small period of the
day when total performance may be affected.
Thermafilm recommends that you look at your whole home envelope of heating, cooling and ventilation so
that you can minimise your condensation and increase the airflow in your home.
For more information contact your Penjerex Agent
Thermafilm Customer Advice - Penjerex Condensation