In order to identify the appropriate insulating solution, it is necessary to analyze how heat and cold flows operate.
Heat moves from hotter to colder zones. This process occurs due to different heat transfer mechanisms. It is important to reduce and restrict heat conduction, convection and radiation transfer in order to reduce and insulate it.
Conduction
It is process by which heat or electricity is directly transmitted through the material of a substance when there is a difference of temperature or of electrical potential between adjoining regions, without movement of the material. Conduction is a natural property of materials.
Heat conductive transmission is measured by Lambda coefficient.
A low heat transmission coefficient means that the insulating material reduces conductive heat leaks. The lower the lambda value, the more efficient in terms of reducing loss of heat by conduction.
Convection
Why is it said heat usually goes up?
When the molecules in a liquid or gas get warm enough, their density changes and the hot air (which is lighter) goes up. This process in known as natural convection.
When this natural movement is accelerated by wind or other artificial elements, we call it forced convection.
When we insulate a closed cell with small cell sizes, convection is inhibited within the cell. Therefore, the cell becomes less likely to affect the surrounding cells and we can control heat transmission.
Radiation
Radiation is energy that comes from a source and travels through space at the speed of light. This energy has an electric field and a magnetic field associated with it, and has wave-like properties.
La radiación es la forma en que el calor se transfiere a través del espacio de un cuerpo a otro como energía.
The rate of heat transfer through radiation is controlled by:
- The difference in temperature between the surface that is radiating heat and the surface that is receiving it.
- The distance between each surface.
- The emissivity of each surface. A low emissivity material repels radiation heat and eliminates “furnace effect”.
An efficient insulating solution also depends on the capacity to reduce heat transmission.
Lambda Value
Lambda Value or Thermal Conductivity is used to measure the ability of a material to conduct heat in an efficient way. Thermal conductivity is measured in W/K*m.
Revestimientos técnicos Sostenibles s.L.
Revestimientos Técnicos Sostenibles S.L.
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An efficient insulating material must have a low Lambda value which reduces heat leaks.
Lambda values are usually considered as general. In order to know how a specific value and thickness affect heat transmission, it is necessary to identify R Value.
R Value
R Value (or Thermal Resistance) is a measure of how well a specific material resists heat transmission. R Value is measured in m²*K/W.
The lower the Lambda value, the thinner the insulating solution and the higher the R Value.
U Value
U Value (or Thermal Transmittance) is the result of all R Values of the whole construction system including fixation setting and air chambers. Thermal Transmittance is measured in
W/m²*K).
In this way we can discover the ability of all the elements (construction system) to transmit heat and cold between different spaces.
The lower the U Value, the more thermally efficient the construction element is.
Building Envelope
The building envelope includes all the building components that separate the indoors from the outdoors. Building envelopes include the exterior walls, foundations, roof, windows and doors.
So that a building can have good thermal insulation and reduce heat loss, in addition to having low values, it must have the least possible number of thermal bridges and at the same time contain the transmission of heat, either by conduction, convection or radiation.
Once you have described how an insulation works and its most characteristic values, we may think that thermal insulating efficiency highly depends on layer thickness.
However, the insulating systems manufactured by RTS can help to control the heat transfer at the same time you reduce thickness because
- All ReveCork and Zeramic Extrem products have low Lambda Values which reduces thermal conductivity. ReveCork products and made from vaporized natural cork being based on thousands of closed, watertight and occluded air cells that achieve a very low heat transfer by convection.
- Zeramic Cells products (based on entrained air microcapsules and low emissivity, with very good SRI rates) control radiation heat transfer.
- This is how RTS insulating products work.
As a conclusion, you will see that there is no need for extremely expensive insulating solutions based on high thickness which mean a lot of money/square meter. On the contrary, RTS products are the low thickness insulating solution and value for money.
