Which film manufacturer puts it in writing the highest % of heat loss

[vquestfilms.com]

The original question s still out here, nOT how to disprove, but rather which company boasts the most heat loss..in writing

I'm not sure you would want to boast about heat loss, reduction in heat loss would be Enerlogic by a long shot. Amazing film when it comes to emissivity.

Is it me or wouldn't you want to advertise "the lowest percentage of heat loss?" Am I missing something?

Sorry, I meant boast the highest heat retention in winter, best film for heat loss

So you are talking about published "emissivity" or "U-value/U-factor?"

[EWF]

They all spout bollocks in one way or another.

Thats whats cool about NFRC, it stops the misleading facts quickly and at this point if it doesn't have NFRC its because its specs aren't what they are claimed to be

Hi LTL,

You're spot on (as usual) but unfortunately they do not publish the Emissivity for window film (per the subject under discussion). Only the VLT and SHGC.

If you want to "keep them honest" a good lab will charge you about $750-$1,200 to run the test and issue a written report.

The only "beef" I have with most Low-E films is that they often have either no hardcoat, or one which is not very durable. Things may have improved recently, so if someone has any light to shed on that, please chime in. I would like to learn more.

We did sell Low-E films at EWF in the past (USA made) but we had enough of the hardcoat complaints and dropped the lines.

As far as manufacturers fudging their specs: I am not saying this does not occur, but I can give you my perspective on this.

A lot of this testing is outsourced to independent specialty labs that do these tests on a contract basis and publish reports. I think it would be pretty embarrassing to take your lab's report and "fluff it up", to suit your needs. The lab that did your testing is not going to be very impressed with you if you take their work and alter it. In most cases the manufacturers and the test labs have established working relationships and I think it would be very uncomfortable dealing with a team of test engineers that know you are "a cheater".

Some allowance can and should be made for measurement errors, variances in production lots, etc. But I find it hard to believe (I certainly hope not) that there is wide scale blatant cheating going on. The published numbers may not be exact, but they are "close enough for government work".

V.C. (may he rest in peace) would take me to task over this post, but I deal with so many folks on the manufacturing end and I would not characterize any of them in any way as "cheaters".

-Howard

-Howard