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Radiant heat reflective clothing

To insulate homes sometimes glass wool is used with on one side a film with a thin layer of aluminum. The glass wool insulates by still air in the glass wool, and the layer of aluminum reflects the radiant heat back.
This radiant heat is also called thermal radiation or infrared radiation.

I wanted to use this same principle to keep myself warm. The insulation by still air can be achieved with synthetic batting/wadding, but also normal clothes will do. The layer of aluminum (or some other metal) should be breathable and must be on the outside. To protect the aluminum layer an extra layer of fabric could be added.
For good insulation, the layer of aluminum must be on the outside. For when the layer of aluminum would be on the inside, then the aluminum is heated by the body, causing it to transfer heat radiation to the environment.
It doesn't matter whether the layer of aluminum blocks the wind or not.
For example, a raincoat doesn't need to be breathable, but because I want to wear it indoors constantly, it is necessary that the fabric is breathable.

Heat Reflective clothes work especially well for inactive people.

After using heat reflective clothing for a few years, it proves to do very well for me. When I'm indoors and I sit still, then normal sweaters and jackets are sometimes not enough to keep me warm, while a layer of heat reflecting material does keep me warm.
When I have more mechanical pressure on my neck, it is harder for me to stay warm. I mainly used an electric heating vest to stay warm before, but clothing with a heat reflective layer proved to work very well and is perhaps also healthier because it does not add external heat to my body.
A healty and active person produces more heat. So for healthy people is enough to put on an extra sweater. It is therefore almost impossible for me to explain to healthy people how big the effect of a heat-reflective layer is.


I started with non-breathable materials with a layer of aluminum:
a few radiant heat reflective materials reflective material reflective material reflective material reflective material
The pictures show: A ground cloth, an emergency blanket, bubble wrap and carpet underlayment.
The emergency blanket is so thin that you can see through it. Yet it works very well. If I wrap the emergency blanket around me, then I notice after a quarter to half an hour that I lose less heat.
The underlayment with a layer of aluminum works also well.
I haven't used the others that much, but I assume they work just as good.

Below is a vest.
I tried to attach bubble wrap with a heat reflective coating to this vest. But I couldn't do it, because it was not flexible enough.
jacket with bubble wrap

It was my intention to buy a roll of flexible and breathable aluminized fabric. I wanted to sew that in a vest, a jacket and a duvet.
A number of brands of reflective material are: XITANIT™, Temptrol™, MIRoTEC©, Sympatex Reflexion©, Aluminet©.
Beside those, there is also lamé
Lamé is a shiny fabric, sometimes used for Christmas clothing. The fabric is woven or knitted, and it consists mainly of a 'thread' of a small strip of plastic foil with aluminum. It is not intended to reflect radiant heat, but it turned out to have a reasonably good result.

This is the sample of Temtrol I received.
sample Temtrol
This material is very easy to cut and sew. It is less flexible and less breathable than woven fabric. If it is firmly rubbed with the aluminum side against another fabric, then the aluminum comes off.


Flammability

All these materials consist of plastic with a layer of aluminum. Because I want to use them as clothing, I wanted to know how flammable they are. So I tried it out.

This is with 3 different kinds of lamé, lying on sand.
When using these as clothing on the outside, then walking along a burning candle is already a risk.

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This is with Temptrol, lying on sand. It melts, but doesn't catch on fire very easy:

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These are the pieces lamé, in free air:

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This is Temptrol, in free air:

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This is a piece of knitted lamé:

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Lamé

I bought a few different kinds of lamé, such as woven, knitted and stretch-lamé:
different kinds of lamé

The material turned out to be difficult to handle, like cutting and sewing. The plastic threads coated with aluminum easily break during sewing.

Below is my duvet cover with lamé:
duvet cover with lamé
For a proper effect, only the topside of the duvet cover has a layer lamé.
I might turn the duvet cover inside-out, so the lamé is protected by the fabric of the duvet cover.
The radiant heat reflection appears to work well. And the material is well breathable.
I only lie on my back, and my top (belly side) was warmer than my back. So I added another layer of lamé under my mattress. After that I stayed nicely warm.
In the winter I used two electric heating blankets (one on top, and one underneath me). But now just one electric blanket is sufficient, and sometimes I don't even have to turn it on.

This is my first garment with lamé:
garment with lamé
It was mainly to see if it could be sawn onto a garment, and to see how the lamé would be if it was worn and washed in a washing machine.

Two years later, and after being in the washing machine six times, the major part of the reflective layer (aluminum) had disappeared.
As shown in the picture below:
heat reflective vest after two years
In some parts the lamé layer was double, and in those parts was still sufficient reflective aluminum present. It also appeared that a higher temperature and a more aggressive detergent in the washing machine were extra disadvantageous for the reflective layer.
The fabric also began to tear.

Until about the year 2008, a heat reflective layer was sometimes used in more expensive jackets. But after 2008 I see this more and more. Beside insulation for building and clothes there are also other applications with heat reflection.

This jacket concists of foil with a layer aluminium:
surviva jak surviva jak
Brand and Type: Surviva Jak
This jacket with heat reflective foil is a very small package when folded. It fits well, it is even for me large enough. A few stickers on the jacket are used to close it.
Using this jacket indoors is not very useful, because of the crackling and creaking sound of the foil.


In 2013, I checked what was available at the moment.
My preference is for a fabric that is good reflective, smooth and breathable.
Below are two fabrics that I bought.

This is stretch lamé:
stretch lame stretch lame
The fabric is very well stretchable in all directions, and it is smooth and strong and the aluminum is firmly attached to the fabric.
It can thus be used on the outside of clothes.
Unfortunately, the fabric is almost not breathable.

The picture below is a plastic foil with a layer of aluminum combined with fleece.
bosal poly-therm fleece bosal poly-therm fleece
Brand and type: Bosal Poly-Therm Fleece
The plastic foil with a layer of aluminum is attached to a cotton-like layer fleece. Also on top is a very thin layer of fleece. This prevents the crackling sound of the foil, and makes it easy to handle like cutting and sewing. The foil is made air-permeable by perforating it with small holes.
This heat reflective foil combined with fleece is the most warm fabric of all heat-reflective fabrics I have.
Because the fleece is fluffy, it can not be used on the outside of clothes.
The foil is not woven, it is therefore not flexible enough to be used in a vest or jacket


The fleece jacket below from Columbia Sportwear is heat reflective.
For the first picture I put the jacket on snowy tiles.
Columbia Omni-Heat jack Columbia Omni-Heat jack Columbia Omni-Heat jack
Brand and type: Columbia Sportswear, Omni-Heat, Men's Heat 360 II Full Zip
The jacket consists of fleece and stretch fleece and has heat reflective dots on the inside. The heat reflective dots are also in the sleeves.
For the maximum effect, it would be better if the heat reflective layer would be on the outside, and would fully cover the surface. The dots occupy unfortunately less than 50% of the surface.
Compared to my homemade garment with lamé, this fleece jack is slightly less warm. My shoulders stay warmer with this jack because also the sleeves are heat-reflective, so in the end the effect is about the same.
The heat-reflective dots do not come off. Due to wear they get less in some places, for example at the end of the sleeves on the inside.

Last change to this page: May 2013