Thermal Insulation: Facts and Fiction
Or: Why neither the myth of mould nor any other tall tales bear up against the reality of a perfectly insulated façade. And what you can do to make your energy-saving dreams come true. With the innovative Baumit ETICS systems, achieving the correct insulation is quite simple.
Energy-saving is happening. Throughout the whole of Europe. In all areas where it is possible. Because in order to save effectively, it is not enough to switch on fewer electrical devices or actively reduce the amount of heating used. A much more significant proportion of total energy consumption can be saved through appropriate "hardware" measures. Even within the existing building stock, that is, all of the buildings in a country. According to a study by the Munich Technical University, the resulting energy savings in Germany - 700 terawatt hours - would be around five times as much as the annual output of all the German atomic power stations put together.
Myth versus fact
To achieve this there is really only one solution: installing thermal insulation composite systems, known internationally as: External Thermal Insulation Composite Systems (ETICS). In the existing building stock as well as new builds. And these systems primarily revolve around one material: Styrofoam. For at present there is hardly anything that is better or more suitable.
Alongside this, for special applications, for example when special materials are required for high-rise buildings, insulation systems are also available that are based on other materials, such as mineral wool.
The pearl among the plastics
The insulation material Styrofoam (or polystyrene) is an invention and protected trademark of the famous German chemicals company BASF ("Badische Anilin- und Sodafabrik"), now the world's largest chemicals corporation. Technically speaking: it is mainly a "closed cell" (the walls between the cells are sealed, and therefore liquids cannot be absorbed), hard foam material, produced through heat treatment of an expandable polystyrene granulate material.
The secret of this material: it contains up to 98% air, with the remaining two percent polystyrene, the cell structure that surrounds the air. This means that Styrofoam is extremely light, insulated exceptionally well against cold and heat and is resistant to mechanical and chemical influences. Styrofoam is therefore often, quite rightly, referred to as the "pearl among the plastics".
An environmentally friendly material
In spite of this, building insulation with Styrofoam has recently been subject to public criticism. It is said, for example, that the "insulation frenzy could result in rubbish mountains as high as the Alps".
However, it is not some sort of madness - the fact is that globally we do not currently enjoy an excess of the material, but on the contrary we actually lack Styrofoam recycling material. This is because Styrofoam waste can be recycled, both mechanically and chemically, making it a sought-after raw material for a large number of recyclers. As an aggregate material in lightweight concrete and insulating plasters, as a pore-forming agent in brickwork, as a material for park benches, fence posts or shoe soles, as a base for other plastics.
Moreover, the fact is that the manufacture of Styrofoam already contributes to conserving our fossil fuel resources and it is also recyclable. Granted, it is a petroleum product, but it requires a exceptionally small quantity of the valuable raw material, as low as just two percent. Over the entire lifespan of the product, it can be calculated that with every litre of petroleum from which Styrofoam is manufactured for the insulation of buildings, in turn, up to 200 litres of heating oil are saved.
And ultimately, there is no recycling problem on account of the fact that the existing thermal insulation composite systems from the 60s, 70s and 80s can be "doubled up": here a second, generally thicker, Styrofoam layer is placed on top of an existing, thin Styrofoam façade.
The myth of mould
Another argument from the critics: Insulation leads to the build-up of mould. However, the opposite is true. Mould develops primarily in places where insulation is incorrectly installed or not installed at all. Insulating materials that are applied correctly to the wall increase the wall temperature and thus minimise the risk of mould. Cold wall surfaces and high air humidity in the room are thus the most frequent causes of mould problems.
However, the residents of buildings that have been renovated in an energy-saving manner, in which the windows have been replaced, must be sensible, and this means letting the air flow in and out from time to time. If insulation is installed perfectly and the room is regularly ventilated, the home will remain mould-free.
Risk of fire lies at one in one thousand
At present, it is the risk of fire posed by thermal insulation systems that is the particular subject of media discussion. These fears can easily be disproved. For example, evaluating the available 2011 fire data in Germany shows that Styrofoam-based thermal insulation composite systems were involved in under one percent of all registered fires - around one in one thousand. It was also evident that the main cause of façade fires was containers that had been set alight and the fire then spread to the façade. It didn't occur to any politician, planner or journalist to ban wooden houses simply because burning containers could be placed in front of them.
Façade burn tests in Austria have also demonstrated that a 30-centimetre-thick thermal insulation composite system made from Styrofoam can resist a fire load for 30 minutes. The spread of fire was not detected on or beneath the surface of the façade within this period. Thus, all protection objectives are fulfilled to an extremely high degree: the residents can vacate the building themselves or can be rescued by other measures, the safety of the rescue teams is taken into consideration and effective fire-fighting operations are possible.
Peak economic value
And finally, doubt is continually expressed as to whether the insulation brings financial savings as large as those claimed.
The answer: insulation always pays off The Internet is full of scientific and practical proof. The optimal insulation thickness, financially speaking, lies between 14 and 33 centimetres. Thus, for example, when renovating a house from the 1970s, around 1,000 to 2,000 euros can be saved each year in energy costs. Under the condition that the investment costs that are required for repairs anyway (so-called "business-as-usual costs") are not taken into account, on average a renovation will pay for itself within around ten years. Business-as-usual costs include, for example, sums for equipment and plastering work if the old façade would have to be renovated anyway. Besides, in some European countries, thermal renovation is actually required for energy-political reasons.
Especially in the case of a new build, by planning correctly in advance the developer or investor can – depending on the size of the project – save up to several hundred thousand euros.
An example: a 16-family apartment block in Munich, planned with ETICS and solid walls made from concrete, sand-lime brick or solid brick with a thermal insulation composite system, can provide up to 70 square metres of additional living space in comparison with monolithic building techniques. Based on Munich construction costs, this amounts to a cool 280,000 euros. If this is translated into the additional rental earnings that can be achieved, taken over a period of forty years this can amount to an income increase of up to 336,000 euros for the investor.
An insulated façade dries five times quicker than other façades. This is just as important in old buildings as in new builds. An old building will have a permanent, albeit low, basic moisture level and will therefore certainly benefit if this humidity is channelled out via the walls. In new builds the problem is often that the construction is carried out quickly, but it can take three to four years for the building to dry out fully. This results in daily humidity. In an average household, around twenty litres of water are released per day – through entirely normal processes such as breathing, showering, cooking and even by house plants. With a correctly insulated façade, all of this humidity will be released outside the building. The risk of mould formation is thus effectively alleviated.
In the southern European countries, there is also a pleasant side-effect: up to 30 percent insulation against summer heat.
A range of state-of-the-art products
Essentially, it is the same as in all areas of life: quality pays for itself As one of Europe's largest construction materials manufacturers, Baumit has developed a range of thermal insulation systems, which respond to the special requirements of the individual construction and the respective countries.
Baumit systems are simply more durable, secure in terms of materials and most of all: more carefully thought through. This is because Baumit offers complete concepts and not individual components, as is the case with other manufacturers. This means: everything fits together, every component is tailored to the next. A compact system such as this consists of adhesive, insulating material, primer and a final coating. Thus, with Baumit, the money you have available is sustainably invested: the insulation works right from the offset and has been proven to last for several decades.