Heat insolation

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Heat insolation

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Heat insolation
Wärmeisolation

What is the basis of the insulating effect of down and feathers?

The insulating capacity which acts as a barrier against cold is one of the most outstanding properties of down and feathers (the capacity to store warmth, heat insulation). This property is grounded on the capability of down and feathers to store millions of insulating air-filled buffers.
 
You know that air is not a good heat conductor.
The insulating capacity which acts as a barrier against cold is one of the most outstanding properties of down and feathers (the capacity to store warmth, heat insulation). This property is grounded on the capability of down and feathers to store millions of insulating air-filled buffers.
 
You know that air is not a good heat conductor. For instance double glazed windows and cavity bricks benefit from this property.
The air between the two layers of double glazed windows has an outstanding heat insulating effect.
 
The same physical principle works with a down- and- feather- filled quilt. The down and feathers form countless air-filled pockets which make up a large percentage of the volume of the quilt. These air-filled pockets make up the insulating layer which prevents the heat of the body from disappearing.

It is almost impossible to examine the filling of finished products and check, whether the composition of the filling was reported correctly on the label.

At this point, you should pay attention to the indications reported on the label. The product properties are confirmed there and the quality standards that apply to the product are indicated.
 
The TRAUMPASS and Daunasan® / Downafresh® refer to the filling. It is stated by NOMITE that the quilt is suitable for house-dust-mite-allergy-sufferers, and the KIS®Komfort Information System is a valuable assistance for you to choose the optimum quilt.
 
 

 

Daunen Wärmeisolation

Why do down have very good heat-insulating properties?

The quilt and the filling themselves do not keep the body warm. The feathers and down make sure that the heat of the body does not disappear, i. e. they store the heat.
 
Down are significantly lighter than feathers. With the same weight they offer a much larger volume. Due to their three-dimensional structure like a flake down are able to store large amounts of air which is not a good heat conductor. The countless air-filled buffers make up the high capacity in terms of heat insulation.
The quilt and the filling themselves do not keep the body warm. The feathers and down make sure that the heat of the body does not disappear, i. e. they store the heat.
 
Down are significantly lighter than feathers. With the same weight they offer a much larger volume. Due to their three-dimensional structure like a flake down are able to store large amounts of air which is not a good heat conductor. The countless air-filled buffers make up the high capacity in terms of heat insulation.
In contrast to the feather, the down is multi-dimensional. Due to its three-dimensional structure and the ability to continuously recover its original shape, a down traps large amounts of air in proportion to its weight.
 
Air is not a good heat conductor. This property works for instance with double glazed windows and cavity bricks to the effect that air forms a protective buffer from cold.
 
A good down filling contains about 2 millions of interweaved and fluffy barbs. Hence, a layer of air is formed which is a poor heat conductor and protects from cold. Due to their resiliency down can be crushed or compressed. If they are thoroughly fluffed up, they will quickly recover their old shape.
 
Wärmeisolation

What is meant by “warmth without weight“?

Among experts, this term describes the capability of feathers and especially of down to offer a high degree of thermal insulation without much weight ensuring excellent sleep comfort.
Among experts, this term describes the capability of feathers and especially of down to offer a high degree of thermal insulation without much weight ensuring excellent sleep comfort. “Down and feathers trap air in between“ is a common phrase in the market.
 
Due to their three-dimensional structure the countless, finely branched down form millions of small air-filled pockets which make up a large percentage of the volume of the quilt.
Since air is not a good heat conductor the countless air-filled pockets make up an insulating layer just like double glazed windows. This insulating layer prevents the heat of the body from disappearing.

The structure and resiliency of down enables down to recover its original volume after having been subjected to specific pressure.
 
 
Source: ARO Artländer GmbH, Kettenkamp.
  
Down and feathers can be compressed to a small volume then. If the pressure, for instance the weight of a human body, is removed, the down and feathers will quickly recover their original shape. Since they are resilient, they can be compressed a billion times and recover their original shape again and again. In the course of this down and feathers form countless air-filled pads which act as an insulating layer.

Due to their three-dimensional structure and the capability to continuously recover their original shape, down store quite large amounts of air in relation to their weight. Since down are very light, they keep the sleeper warm and comfortable without much weight.
 
Wärmeisolation Vorteile von Daunen- und Federbetten

Is it true that heat is likely to accumulate under featherbeds?

Down-and-feather-filled duvets are always capable to regulate the climate in bed. The idea of heat accumulation under a down–and-feather-filled duvet might trace back to the “bulging balloon bed” shown on the pictures in Wilhelm Busch´s classic children´s stories. However, scientific research on the subject “micro climate in bed“ revealed that high temperatures do not occur under featherbeds, even less under a down-filled duvet which is light by nature.

Further information at :

Down-and-feather-filled duvets are always capable to regulate the climate in bed. The idea of heat accumulation under a down–and-feather-filled duvet might trace back to the “bulging balloon bed” shown on the pictures in Wilhelm Busch´s classic children´s stories. However, scientific research on the subject “micro climate in bed“ revealed that high temperatures do not occur under featherbeds, even less under a down-filled duvet which is light by nature.

Further information at :

Federn Wärmeisolation

What kinds of feathers offer favourable heat-insulating properties?

Due to their chemical structure, feathers are poor heat conductors. Besides, they form millions of small hollows (air pockets) imbedding a large volume of air which acts as an insulating layer.
 
Goose and duck feathers have a curved and soft quill which brings about excellent fill power, i. e. the capacity to unfold the largest possible volume again and again, at the same time imbedding millions of insulating air pockets.
 
Chicken feathers, however, have a flat shape. The main part of the quill is flat, i.e. the firm shaft in the middle.
Due to their chemical structure, feathers are poor heat conductors. Besides, they form millions of small hollows (air pockets) imbedding a large volume of air which acts as an insulating layer.
 
Goose and duck feathers have a curved and soft quill which brings about excellent fill power, i. e. the capacity to unfold the largest possible volume again and again, at the same time imbedding millions of insulating air pockets.
 
Chicken feathers, however, have a flat shape. The main part of the quill is flat, i.e. the firm shaft in the middle. They are not resilient enough to “fluff up“ again, for instance after having been compressed by the human body. Therefore, they are less suitable as filling material for pillows and duvets than the plumage of waterfowl.
 
Goose and duck feathers place underneath down as well as regards fill power and insulating capacities. Nevertheless, they are frequently used as filling material for pillows - partially in combination with down.
 
Further information at DOWNAPEDIA:

 

Wärmeisolation Decken

Why do down-and-feather-filled duvets provide such a favourable micro climate?

Bedding products filled with down and feathers are capable of providing a high degree of thermal insulation with a low filling weight. The comparatively low filling weight is a significant factor for sleeping comfort – the duvet is supposed to keep the body warm with very little weight.
Humidity is another important criterion for the climate in bed.
Bedding products filled with down and feathers are capable of providing a high degree of thermal insulation with a low filling weight. The comparatively low filling weight is a significant factor for sleeping comfort – the duvet is supposed to keep the body warm with very little weight.
Humidity is another important criterion for the climate in bed. Bedding products filled with down and feathers are capable of absorbing and transmitting the body's humidity so that it is not perceived by the sleeper as being uncomfortable. A scientific study confirmed the favourable micro climate created under down-and-feather-filled duvets and clearly showed that there is no heat accumulation under featherbeds.
 
In the scope of a scientific study conducted by the University of Kiel in 1992, the issue of what impact the duvet has on the micro climate of the bed was investigated in particular.
As part of a major study with test subjects, 14 duvets were investigated, which reflect the supply of bedding products currently available on the market, both with regard to the materials used and to the filling quantity (e.g. fillings made of animal hair, silk, synthetics, down and feathers).
 
For these studies three groups of candidates, namely persons with mild, medium and strong perspiration, were selected so that the whole spectrum of the requirements of a person for a duvet were able to be covered.
 
During a test with comparable bedding products, the focus of the study was on whether or not the assertion is true that there is heat accumulation under featherbeds.
 
Heat accumulation is characterised by an increase in the core temperature of a person, so that the sleeper starts to perspire exorbitantly. The duvet was unable to compensate for the temperature in a suitable manner
 
The tests conducted with different duvets were able to clearly show, however, that inappropriately high temperatures in the bed hollow do not occur under normal bedroom conditions for any filling material, and therefore, also not for featherbeds.
 
Wärmeisolation Austausch

Suddenly the duvet does not keep the body warm any longer. Why?

Since down and feathers are natural materials they undergo a certain natural ageing process. In the course of time the filling gradually desiccates and you will find an increasing number of broken and damaged down and feathers. You can slow down the process by proper care (fluff up the duvet or pillow every day and air them regularly), but you cannot stop it.
 
If your duvet is not worn out, you should have it cleaned to remove residue such as sweat.
Since down and feathers are natural materials they undergo a certain natural ageing process. In the course of time the filling gradually desiccates and you will find an increasing number of broken and damaged down and feathers. You can slow down the process by proper care (fluff up the duvet or pillow every day and air them regularly), but you cannot stop it.
 
If your duvet is not worn out, you should have it cleaned to remove residue such as sweat. Besides, worn out filling components, in particular broken down and feathers are picked out and replaced by new material.
 
If your duvet has been used for a very long time, it will hardly be worthwhile to have it cleaned. You should rather consider to purchase a new one.
It is generally advised to replace a pillow after 5 years of use at the latest. You should purchase a new duvet after 8 to 10 years.

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