How to make single glazed windows more energy efficient?

[fadetoblack]

Hi All, 
I recently bought an old town house with predominantly west facing single-glazed windows and am now looking at adding an extra glaze to the windows to make it more energy efficient. 

Due to budget constraints, I'm looking at a DIY project using either acrylic and/or polycarbonate materials for the second glaze. 

I'm just writing to see if anyone has any recommendations on using the two materials?
Can both materials be pre-treated – maybe with a tint?– to block UV and mitigate direct sun?
Also, for the sake of better security, is it possible to install the polycarbonate panels on the outside (first floor anyway) effectively? 

Any tips on the subject would greatly appreciated. 

Thanks in advance, 

[RichardC]

Hi,

I have successfully used double walled polycarbonate sheets on the outside of windows as a cheap/light alternative to double glazing.

I sealed the cut ends with clear silicone to trap the air inside & then attached them directly to the glass with more clear silicone just around the outside edge. The view is a bit obscured, but light still gets through & the glass inside doesn't get as cold as it used to, so no condensation.

Regards,

Richard

[EricL]

Hello @fadetoblack 

Thanks for sharing your question about double glazing your window. Would it be possible for you to post a few photos of your window frame both inside and outside. This will give our members a better idea of its construction and configuration. We can then make recommendations on how to mount the polycarbonate sheet to your window frame.  

If you have any other questions we can help with, please let us know.

Eric

[EricL]

Hello @RichardC 

Welcome to the Bunnings Workshop community. It's wonderful to have you join us, and thank you for sharing your knowledge and experience regarding double glazing your windows.

It's great to hear that you've managed to double glaze your own window with polycarbonate. Would it be possible for you to post a few photos of your project? I'm sure our members would be keen to see how you did it.

Again, thank you for sharing your knowledge and experience regarding double glazing.

Eric

[fadetoblack]

Thanks Eric.
I just uploaded some images.

[fadetoblack]

Thanks Richard, 
would it be possible for you to send a photo of this job. 

Cheers,

[Dave-1]

Afternoon @fadetoblack 

I havnt used polycarbonate materials per say... But have used old CD/DVDs as a glazing to trap air between the window and the edge of the window sill.

Recycled CDs used as window curtain 

Previously I had a sheet of white paper stuck to the glass andwa sconcerned when i installe dteh cd's that the temperture would rise. It rose maybe a degree compared to the white paper, it stayed cool through the height of summer even with the door open. It allows light to enter and gives privacy at the same time. 

Recycled CDs used as window screen 

This one worked extremley well. The foyer is so much cooler in summer and strangely in winter it is warm. Paperclips, Cd's and timber trim plus cup hooks were the materials I used.

I figure the heat/light is trapped between the glass and the reflective surface of the CD's and bounces back out only getting to heat that air in between (havnt used a temp gun on it yet but now you have me thinking)

Would really like to see how you go about with your double glazing. Or maybe even hang a sheet of polycarbonite from the top of the window instead of sealing it?

Dave

[fadetoblack]

Thanks Dave, this sounds like a very creative approach. I’m fascinated  by how it all works.

re acrylic or polycarbonate double glaze, there are heaps of videos  on YouTube illustrating, - mainly by elderly British people - how to install them and the benefits of doings so. 

[RichardC]

Hi Eric & fadetoblack,

Initially I attached the double walled polycarbonate panels to the outside of the glass with double-sided tape. That worked fine for a couple of years, but the window is North-facing, the UV got to the tape & one panel fell off, so knowing it worked, I bit the bullet & then attached it with silicone. Obviously you can see the silicone from the inside so a small, consistent bead is best.

My window is in a bathroom, so the partly obscured view in/out isn't a bad thing. I wouldn't use it across a nice view. I think it works best horizontally, not vertically. If vertical, the warm air would gather at the top of the tubes whilst the bottom would get cold. Horizontally prevents this from happening.

Regards,

Richard

[Dave-1]

Afternoon @fadetoblack 

Yeah I have gone down that rabbit hole as well One thing I try and keep in mind when I am look at English or European stuff is it is from countries a LOT colder then here. So What workes really well for them may only partially work here. I like the idea of sandiching an air gap between two surfaces. Its why curtains do such a good job. And using other materials is something I dont mind trying. 

I want to do the same cd/dvd curtain as a seperator for the back of the house in winter. Really i should get some temperture sensors to quantify the information

Dave