ABC of insulation

Thermal Insulation – Basics

Thermal insulation acts as a barrier to the movement of heat, therefore slowing down the escape of heat from a building in winter (when the outside temperature is lower) and the entry of heat into a building during summer (when the outside temperature is higher).

To change the temperature of an object, energy is required in the form of heat to increase temperature (e.g. by using heaters), or reduce temperature (e.g. by using air conditioners). Once the heat generation or heat extraction stops, a reverse flow of heat happens and the temperature returns to ambient. To maintain a given temperature considerable continuous energy is required. Insulation reduces this energy loss.

 

Heat moves though a wall or inside the roof space by any of the following means:

  • Radiation – caused by direct incoming infrared radiation
  • Convection – caused by the movement of air currents
  • Conduction – caused by heart moving by touch from one material to the next

 

The movement of heat in, say, a roof-space is achieved by all three means but mainly by convection and conduction.

Certain insulating materials act as radiant barriers, convective barriers and conductive barriers. However, certain very commonly used materials such as foil insulation contribute almost exclusively to the control of radiation only, by reflecting heat. The purpose of Eco-Insulation is to trap a dormant layer of air inside a stable fibrous insulation layer. This effectively stops convection and conduction by means of the entrapment of a large volume of air, a poor conductor of heat.

 

What to look for when buying insulation?

Look for the "R-value." "R" means resistance to heat flow. The higher the R-value, the greater the insulation power. The R-value must be disclosed for most insulation products. (Pipe and duct insulation are the exceptions, although duct wrap is covered.) For instance, if you buy loose-fill insulation with an R-value of 1.97 from Company A, it will have the same insulating power as loose-fill insulation with an R-value of 1.97 from Company B. You also can compare the R-value of one type of insulation to another, such as loose-fill to blanket.

 

What is R-Value?

“R” stands for resistance to heat flow or Thermal Resistance Value. The higher the R-value, the greater the insulating effectiveness. R-value is measured through a series of industry standard tests. Manufacturers of insulation products print the R-value of their products on either bags or on labels attached to plain bags. In most cases, R-value is also printed on the facings of batts and rolls. On un-faced insulation, R-value may be printed on the product or indicated by stripe coding.

 

R Value = thickness of insulating material ÷ thermal conductivity of material.

 

With the introduction of uniform standards for measuring the effectiveness of various insulations, the Thermal Insulation Association of South Africa, TIASA, has introduced a range of total recommend R-Values for each of 7 different Climatic Zones. Results are in fact, the TRV’s of the total system – including static air gaps and roofing materials – and cannot be compared with R values of the bulk insulation products. Make sure that test methods used are clearly declared in order to avoid a poor basis for comparison between different types of materials.

 

(SEE PRODUCT TAB FOR Eco-Insulation’s Thermal Conductivity Chart)

 

Why install insulation in your home

  • Warming and cooling your home, home comfort control
  • Lowering energy consumption
  • Suppressing noise
  • Providing fire resistance
  • Increasing your resale value
  • Lowering your carbon footprint with a natural safe, recycled insulation product

 

About Energy Efficiency:

Energy consumption in South Africa measured against output (GDP) is very high compared to other countries. In the past, the use of insulation materials & techniques has been very low. There is a misconception that insulation in building is not essential and regarded as a luxury item due to the low cost of electricity.

 

This is changing rapidly; cheap fuel such as coal has not been used to South Africa’s advantage as a non-renewable resource and has rather been wasted by burning for energy (electricity). This is very bad for the future because the abuse has diminished our long-term resource and contributed to creating environmental pollution and ultimately global warming. Also peak demand for electricity during the winter exceeds capacity, which Eskom can cost effectively supply to most homes at an affordable rate.

 

The first low-cost homes that were built under the RDP were highly energy in-efficient. With the introduction of SANS 204, “Energy Efficiency in Buildings”, by SA Bureau Standards, this is set to change and developers will be considering what materials to specify in their projects in order to achieve efficient thermal performance.

 

Eco-Insulation represents a highly cost-effective and extremely safe choice for both ceiling and cavity thermal insulation. Eco-Insulation recently had the honour of receiving the Southern African Energy Efficiency Association’s Company of the Year Excellence Award, 2008.

 

Users of Eco-Insulation have the peace of mind of knowing that they are using an excellent product, that also contributes to the environment by supporting recycling and lowering the consumption of electricity.

 

Acoustic Insulation – Basics

Acoustic insulation is used to reduce noise inside a room such as a hall, or to keep the noise from entering that room.

 

  • Firstly, a sound wave travelling in the air outside the room may strike the outer wall of the room and set it vibrating, thus passing on and generating a sound wave inside the room.
  • Secondly, machinery operating inside a building can also cause wall vibrations, thus passing the sound waves on. Thus, machinery must be insulated by placement on shock-absorbing materials such as rubber pads. Exactly the same principle applies to noisy wooden (upstairs) floors. However, walls can also absorb and pass on noise that passes through the air. This is why it is necessary in some cases for walls themselves to be insulated, so that the sound waves are absorbed before being passed through.

 

Eco-Insulation has a natural ability to become an integral part of the wall, floor or ceiling by filling all the gaps and irregular spaces and thereby producing a significant improvement in noise suppression. Due to the porosity of its interwoven fibres, cellulose insulation is able to absorb low and high frequency ranges within an enclosed wall or ceiling cavity. Cellulose fibre has a NRC-Noise Reduction Co-efficient of 0.90 (90% of sound energy absorbed).

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