Keeping my sunroom warmer (making interior storm windows)
 

Last year was our first year using the sunroom. We love the room and all of the 13 windows, but that does come with a price once the sun sets. The windows are newer and of decent quality. Still, I believe they probably have an R value of 2-3 where the wall has R20 insulation. So, they loose tons of heat at night.

I'm really looking for a semi-permanent way of reducing heat loss through these windows. Something I can put up in fall and take down in summer. I don't want to use those disposable films as this will be a requirement year after year.

My innitial idea (and only one really) is to remove the screen in winter and replace it with a piece of lexan or plexiglass. They would clip in with the pins that hold the screen in currently (spring loaded goes into the window frame). I would add a gasket to the inside of the plastic to seal it. This will add another air pocket just like the disposable film does and help insulate further. However, it will be reusable every year.

I'm open to any ideas, so toss em out there. :)

This is the room before we moved into it. I'll get more detailed/updated pics later on.

http://www.tercelreference.com/downloads/house056.jpg

Oooh, I just thought of another one. Adding tracks to the sides of the blinds. They are the double honeycomb type and do provide some insulation IF they sealed better on the sides. I could add rails/tracks on the side to reduce air movement past them.

I'm really not a huge fan of closing the blinds on 13 windows every night, but if it helps...

I found some very good stuff on builditsolar (as usual). :)

Home Energy Conservation

I'm especially interested in a frame designed interior storm window. You take a 1x2 and cover each side in film. Then, you shove it into the window cavity and bingo, two more air pockets. Sounds like a great idea, but I shall continue reading.

Still looking for suggestions though!

Storm windows, shutters?

Can't do external storm windows or shutters. There isn't enough room between windows, and they are mounted flush with the outside of the house. However, this does leave a fairly deep sill to play with on the inside.

http://www.tercelreference.com/downloads/house034.jpg

My parents have a sun room about the same size and they have window quilts that cover 3 windows at a time, 1/3 of the number of shades to close, they have a layer of silver mylar between the layers of quilt batting giving it I think an R value of R6-8 if I remember correctly.
Alot of the heat loss from windows is the radiant heat.

Do you have any information that quantifies the radiant vs conduction losses through a window?

Bumping for ideas since the forum is clean again.

I think this idea is probably the simplest and perhaps best. Removing the screens should boost your solar gain by +/- 30% (depending on the screen). Adding a storm window / lexan / plexiglass uses the existing hardware and doesn't interfere with window or blind operation.

I'd check with local hardware stores and glass shops to price simple framed storm windows built to fit where your screen does. I'm not sure about lexan / plexiglass and how well they weather over time. My experience is that thin plexiglass can be very wobbly and get brittle in time. There may be better, weather-resistant plexi and lexan formulations that are more durable.

Let us know how it goes,
Tim

I'm kind of leaning toward the frame with film on it. Mainly this is due to the higher r value it will provide. I'd like to get as much as possible.

http://www.arttec.net/SustainableLiv...erm/index.html

http://www.arttec.net/SustainableLiv...EP_diagram.jpg