Jump to content

Can any solar film raise the R Value by 1 point?

Recommended Posts

Hello smart people, hope everyone is doing ok in these crazy times! 


I received a call from a commercial glass company who are looking for a window film that will raise the R-value of their triple pane units by 1.

The exterior pane being heat treated. The other two interior panes are regular annealed glass. There is a low-e coating on surface #2 (starting from outside)

They would like to keep the look of the glass as neutral as possible, if possible.

The larges panes are 54-1/2” x 72”.(approximately 60 panes)

If there is such a film, I would need to submit something tangible that would show the science.behind the madness.

Any info on this would be much appreciated.


thanks so much everyone, stay safe!!

Link to comment
Share on other sites

R value is the U value of a material divided into 1 as a standard so that commonality can be found across dissimilar materials. U value is a percentage because flow rate of energy is important but actual degree measures are not useful.  A brick has an R value of 4. Why? Because 1/.25=4. The U value of a brick is 25%. that means 4 degrees go in one side and 1 comes out the far side. Or 40 go in and 10 come out or 100 go in and 25 come out. U values on products like Enerlogic are given around .62 these days. 1/.62=?. So in the overall measurement of the R value of a window of course the frame comes into play. The frame is roughly 25% issue, made problematic by the reality that the more solid a material is then also the better it conducts and holds energy due to its mass.


If you did the little math I left for you then you should also know that R values of materials are sums. They add together like you wearing multiple shirts.

Edited by Tintcutter
spelling as usual
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Create New...