Newbie here (1st post).
I was wondering if anyone has had experience with the 'Enerlogic' films for Windows.
ncl_knight said:They make some pretty impressive claims.
Their sales spiel certainly does...
ncl_knight said:I have a 'Queensland Room' which has large, single glazed windows. We really didn't know much about the building process, and believed everything the salesman said. Needless to say, I won't be falling for that again
ncl_knight said:Anyhow, in order to give some insulation qualities to the Windows, I found the Enerlogic site, and it seems really good.
I thought you said
ncl_knight said:I won't be falling for that again
There's a saying that if it sounds
ncl_knight said: too good to be true.
it probably is...
It's not strictly untrue, it's just presented in a way that the unwary will be inclined to extrapolate the claimed benefits into situations where they simply do not apply.
There are three heat transfer mechanisms and this film address only one of the three - radiation. It is a low "e" film that reduces the glass pane's transmission of infra red radiation. Imagine that your windows become mirrors, reflecting the outside heat out in summer and the inside heat inwards in winter. That's the good bit...
If you have well positioned windows that allow winter sun in and block summer sun, then this film will be a disaster, doing exactly the opposite of what you want. So use it on north facing windows with caution. But it would be good for unshaded west and east windows. It isn't going to do much on south windows unless you have a large radiant heat source outside in summer - like a nearby wall, or a large area of glass on the south side of a room with radiant heating such as a fire, underfloor or in-ceiling coils. For R/C or gas ducted heating, the radiant energy in the room is lower, so the benefit will be lower.
The other two mechanisms are conduction, where double glazing or secondary glazing will beat the pants off this film for efficiency, and convection or drafts. If your house / room is leaking like a sieve, no amount of window treatment is going to do very much. You just have to pour the heat in as fast as it blows out.
To be honest, this film is really useful for very specific circumstances where reducing radiant heat gain or loss is important and there is no other way to do it, such as skyscrapers, or high solar gain windows where the view is more important than the energy bill.
Posted Saturday 25 Aug 2012 @ 6:25:16 am from IP #