23 March, 2006
Tim Renouf
Wren Industries P/L
139 Herald St
Cheltenham VIC 3192
Concertina FOIL BATTS between roofing rafters
Dear Tim,
In 2003, I bought a house in a Mirvac estate The Heath, Heatherton, in the south-west of Melbourne. The two level
house itself is a very modern contemporary design. Mirvac installed some foil insulation under the black tiles but only
in a couple first rows of tile work, which is not enough. They also installed fibreglass insulation on the ceiling.
We moved into the house in August 2003. As August is not a very hot month we did not know what would happen
when hotter days arrived. In October we started to be aware of the large
amount of heat upstairs and it was difficult
to live or sleep at night. I knew that the builder has installed some insulation and I did not want to complain much
about the heat problem.
In November 2003, I decided to install a central airconditioning system to be prepared for the increasing summer
heat. After installation I did not get much improvement in the second level and I started to complain about the
airconditioning. People from Dandy Air came and tested the unit and said everything was fine. As I was not
satisfied with the testing I called Lennox, the manufacturer of the airconditioning system, to investigate my
problem with the heat. I remember that one of the technicians measured a starting temperature of cooled air
generated at 9 degC, and on one of the outlet points discharging cool air into an upstairs room, the temperature
was 19 degC. From start to finish, that was a 10 degC increase in temperature of the cooled air passing through the
airconditioning ductwork which is laid across the roof space.
I was complaining for two years and finally gave up in December 2005.
Then I started to think about insulation and
to take some action in that way. After I visited the Home Ideas Centre in Clayton, I contacted Tim Renouf at Wren
Industries who explained to me that the reason for my problem with airconditioning not working properly is that
the fibre insulation around the ductwork is not able to cope with the intense heat radiating down from the roof tiles.
He said this heat can be around 70-80 degC which makes it extremely difficult for the airconditioning system to
operate efficiently.
Firstly, I installed two roof fans and achieved a two degree C drop in temperature upstairs. Following this I
have stapled Tim's product Concertina FOIL BATTS between all the roofing rafters as well as also wrapping
FOIL BATTS around the ductwork. The room outlet temperature now recorded 12 degC this is 7 degC lower
compared to the original 19 degC. Now my airconditioner is starting to work properly and it can much more easily
maintain thermostat temperature settings of 24-26 degC and will have much lower running costs.
Better advice is needed about how different insulation products work. It seems clear to me that fibre insulations dop
not work properly in stopping high temperature radiation. Thankyou to Wren for their advice and great product.
Regards,
Miro Belic
77 St. Andrews Drive, Heatherton VIC 3202
bmiro@netspace.net.au