Insulation Value of Window Coverings

GaryBIS said:

Hi MSNomer,
Your initial results:
Results:
Ambient: 24° (Colder than I expected)
Van Interior: 68° (Warmer than I expected)

Quilt Alone: 62° inside surface, 61.5° outside surface

Quilt with white light-blocking fabric: 64.5° inside surface, 51° outside surface

Quilt with thin reflective fabric: 64° inside surface, 40.5° outside surface

The progression seems right for the different treatments, but could you get one more set of readings?

I will set it up again tonight.

Its interesting to have the temp of the outside surface of the shade. I guess you are getting that by quickly pulling the shade in and getting a reading on the back? It should be helpful to have these as it will show how much of the temp drop is over the shade itself.

Both front and back of shade have tape, and yes, I quickly pulled it back and measured. Is there a better way? None of these has stitching in the middle, just around the edges. The "middle" one with light-blocking fabric hangs loosely enough that there is probably a gap between inside and outside fabric. The extreme one at the rear is resting against the insect screen, so its layers are probably touching.

I'm a bit puzzled by the big drop in temperature of the outside surface for the last one (40.5F).
It would be good if both the front and back of shade had the painters tape where you take the reading - this will keep the IR gun from getting confused by the reflective surface.

All measurements were from green tape surface.

Can you also get a reading on an adjacent window with no shade? Just put some painters tape right on the inside of the glass. This can then be the baseline for all the window treatments.

I will do that.

Since the inside temperature probably varies around the van, best to get the inside air temp with a thermometer placed a few inches in front of the window you are getting the shade measurements on.
Are the different shade constructions all being measured on the same window? That is, measure quilt alone, then add light blocking fabric and measure again? If so, good to allow some times for things to stabilize.

All curtains were set up in their intended positions before I went to bed and measured early morning, so nothing was disturbed except to pull the corner back to quickly take the outside measurement. The ambient thermometer was set a few inches from the window with light-blocking fabric.

For the ambient measurements, what if I put some green tape on upturned plastic cups situated on the bed near each window?

Gary

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rjcarter3 said:

I finished hanging all the reflectix shades in my PM which make it practically pitch black in there and completely dark outside as well when I have the full lights on. Is there any reason besides aesthetics and some R-value gain from some of the other bulkier ones? For the cab glass, I bought some from YellowPro on Amazon and can't recommend them highly enough. Seem to be much better quality than off the shelf stuff from Lowes or HD and fit absolutely perfectly.

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MsNomer said:

For most people, windows are a minor portion of their "envelope." For me, they are essentially the entire mid-height section. Not only are the windows themselves maximum size all around, but there is no "box" around them, as many have, so the entire recessed area is either glass, aluminum or bare steel.

Several years ago, I made coverings for the side windows from a cheap Walmart quilt with the fake glued-together "stitches." The primary use has been for blocking unavoidable bright lights at night. I decided that this year's winter project will be to upgrade them, but I like the look of the existing ones so well, I decided to improve them rather than start from scratch.

View attachment 82179

View attachment 82180

The windshield screen doubles as a barrier between cab and rear.

Amazon.com

I have been using an identical one across the rear, but decided to upgrade to a quilt one. It wraps under the mattress and connects with the side curtain to insulate the living space not just from the rear windows, but from the entire rear area including the D-pillars. This is its first mock-up.

View attachment 82181

As you can see in the photograph, this quilt fabric is not blocking light very well, so I decided to add light-blocking fabric. As soon as the clerk handed me the folded fabric, I knew I could not use it on the rear curtain—its weight would pull the curtain off its magnets. It will work for the side curtains because they hang on hooks. For the rear, I bought the Class A sized version of the windshield cover and will attach the fabric with the shiny side out.

Sooo, I have three scenarios to test and compare if the cold weather lingers around long enough—quilt alone, quilt with heavy impervious white backing, and quilt with thin but reflective backing.

I have already determined that I can have at least a 25° differential across the original. (HF laser gun, surfaces taped per Gary's suggestion.) Given that I can practically see through it and a large percentage of its surface area is squished flat, this surprises me. Reflecting on the concurrent discussion of the R-value difference between Thinsulate and Polyiso, I wonder if the R-value of this fabric can even be measured. However, we both notice the substantial rush of cold air when it is removed.

More tomorrow, I hope. Any suggestions, @GaryBIS?

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MsNomer said:

For most people, windows are a minor portion of their "envelope." For me, they are essentially the entire mid-height section. Not only are the windows themselves maximum size all around, but there is no "box" around them, as many have, so the entire recessed area is either glass, aluminum or bare steel.

Several years ago, I made coverings for the side windows from a cheap Walmart quilt with the fake glued-together "stitches." The primary use has been for blocking unavoidable bright lights at night. I decided that this year's winter project will be to upgrade them, but I like the look of the existing ones so well, I decided to improve them rather than start from scratch.

View attachment 82179

View attachment 82180

The windshield screen doubles as a barrier between cab and rear.

Amazon.com

I have been using an identical one across the rear, but decided to upgrade to a quilt one. It wraps under the mattress and connects with the side curtain to insulate the living space not just from the rear windows, but from the entire rear area including the D-pillars. This is its first mock-up.

View attachment 82181

As you can see in the photograph, this quilt fabric is not blocking light very well, so I decided to add light-blocking fabric. As soon as the clerk handed me the folded fabric, I knew I could not use it on the rear curtain—its weight would pull the curtain off its magnets. It will work for the side curtains because they hang on hooks. For the rear, I bought the Class A sized version of the windshield cover and will attach the fabric with the shiny side out.

Sooo, I have three scenarios to test and compare if the cold weather lingers around long enough—quilt alone, quilt with heavy impervious white backing, and quilt with thin but reflective backing.

I have already determined that I can have at least a 25° differential across the original. (HF laser gun, surfaces taped per Gary's suggestion.) Given that I can practically see through it and a large percentage of its surface area is squished flat, this surprises me. Reflecting on the concurrent discussion of the R-value difference between Thinsulate and Polyiso, I wonder if the R-value of this fabric can even be measured. However, we both notice the substantial rush of cold air when it is removed.

More tomorrow, I hope. Any suggestions, @GaryBIS?

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MsNomer said:

I began to wonder whether the actual temperature of the gun was having an effect. That 16° was certainly having an effect on me. 🥶

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