Analysis of Technical Characteristics of Building Materials in the Construction of a Single-Family Building from Natural Materials

In writing the diploma thesis, he presented technical data of the most important natural materials such as straw, wood, stone, clay, which are used in house construction. He presented the comparison of natural building elements in various tables. In the final part of the analysis of walls made from natural materials and brick walls, based on a price comparison of data obtained from Merkur and Ytong building shops and a local farmer, where he compared the prices of straw bales and brick walls, he came to the conclusion that construction from straw bales, which are one of the materials for building naturally constructed houses, is cheaper than those where the basic material is brick masonry, i.e. the classic method of construction.

Problem

In writing the diploma thesis, he presented technical data of the most important natural materials such as straw, wood, stone, clay, which are used in house construction.

Solution and Method

He presented the comparison of natural building elements in various tables. He also described the technical, mechanical and physical properties that are important for construction with natural materials. The basic building materials that humans used for construction were precisely clay, stone, wood and straw.

We live in a time when we are increasingly aware of the importance of preserving nature and protecting the environment. Nature offers us the most favourable and most economical shelters. If we give natural materials an opportunity or utilise them well, we can ensure a cleaner and healthier future.

The author in the diploma thesis devoted himself primarily to questions of comparability between houses made from natural materials and classically constructed houses, and on the basis of hypotheses set in favour of natural materials, he wished to confirm the set hypotheses.

Results

In the final part of the analysis of walls made from natural materials and brick walls, based on a price comparison of data obtained from Merkur and Ytong building shops and a local farmer, where he compared the prices of straw bales and brick walls, he came to the conclusion that construction from straw bales, which are one of the materials for building naturally constructed houses, is cheaper than those where the basic material is brick masonry, i.e. the classic method of construction. With these findings, I dare to answer the first hypothesis affirmatively: 'Natural construction is cheaper than classic construction', also with the facts that in a naturally constructed house from straw bales, according to his calculations mentioned in table 20 in the diploma thesis, the price is 10,999.22 euros, whilst in classic construction, the price is slightly higher, as construction with bricks amounts to 11,738.11 euros for an external wall area of 177.85 m², without windows.

The calculation included only material, without labour. In addition to the lower price of construction from natural materials, a more cost-effective variant of a constructed natural house is also represented by the fact that materials can be obtained directly from nature – from local raw materials. The purpose of the diploma thesis was to increase the use of natural materials and to draw attention to the importance of natural materials on their well-being and health, and thereby also confirm the second thesis: 'A house made from natural materials is more friendly to the environment and life'.

I could not obtain faster execution of house construction from natural or classically constructed houses from the study, as other factors also influence the speed of execution. When studying the literature and analysing the advantages and disadvantages of construction from natural materials, I find that ecological materials used for the construction of natural houses decompose more quickly, natural materials themselves do not contain chemicals and unnatural harmful substances dangerous to the environment and humans, and are thus more friendly to the environment, which has a positive effect on their health.

Many artificial materials that decompose over a longer period and which in some cases require thermal and chemical treatments for decomposition have a negative impact on their environment and on ourselves. Straw as one of the basic materials for building structures is a very economical and ecologically good building material that can also be used in modern construction. The advantage is the quality of living in such a space, as a wall made from straw bales, plastered with clay, effectively and naturally regulates humidity in the space.

Straw does not emit any toxic substances and is thus a very nature-friendly material. At the same time, it also breathes, which means it enables natural ventilation of the building. Wood, as another most common building material, is the most energy-efficient of all materials.

It is naturally renewable and meets the principles of sustainable development. In a house that is built from wood, the living climate is also much better than in a building with other, mainly artificial materials. The downside of wood is its lifespan, which compared to other materials (steel, concrete) is short, but wood can also be recycled and despite its impermanence does not have as much negative impact on the environment and on people. Clay has shown its usefulness throughout history and was already considered in the past to be suitable, safe and durable building material.

Likewise, clay materials give buildings a more pleasant and much healthier living environment than modern materials. It enables moisture to be absorbed from the space and released again under different conditions, which means that there is always approximately 50% humidity in the house throughout winter.

It regulates heat and ensures that the space is cool in summer and warm in winter. Most importantly, this natural building material also satisfies physical building and ecological requirements and is very favourable to the environment and people. Just like wood, clay can also be recycled, which means that if we add water and grind it, we can use it again.

Clay solidifies through cohesion by mixing clay particles. We call such a process reversible, as clay softens with the addition of water. Buildings that are constructed from clay must be well protected from meteoric and capillary water, which is a weakness of clay, but despite some weaknesses, it has good potential to represent environmentally and people-friendly building material. In the analysis section on natural materials and brick blocks, with the help of the URSA4 computer programme, he wished to obtain data with which he would confirm or reject the final hypothesis, namely: 'Natural house construction with natural materials has better insulation'.

The calculation of thermal conductivity of materials of equal thickness showed in favour of straw bales (0.110 W/mK), which, as in many cases, is the basic material of naturally constructed houses. According to the results, it is followed by brick material such as 'YTONG TB 40', but the thermal conductivity between straw bales and brick material is still not negligible. In terms of thermal conductivity, brick blocks with a small difference value (0.308 W/mK) are followed by wood (0.482 W/mK) and finally stone (2.927 W/mK). The results of specific transmission heat loss through external surfaces also showed in favour of a wall constructed with natural materials – clay and straw bales.

I assert that the construction of a house from natural materials, where the basic building material is straw bales, is certainly much more insulative than construction with brick material, which was also confirmed by fire safety tests carried out in Austria, which also positively confirm the fact that a wall made from straw bales and plastered with clay is very well protected against fire. Tests have shown that straw bales are more convincing than classic material in terms of sound and thermal conductivity. As for wood, I cannot fully confirm its good insulation.

The fact that the insulation of natural materials is better, as learnt from the analysis in the diploma thesis, cannot be completely generalised to all natural building materials. Despite some negative aspects of natural materials mentioned in the diploma thesis, I believe that if we exploit all the positive properties of natural building materials, we can expect in the near future an increase in the construction of healthy, environmentally friendly, cheaper and in some cases more insulative buildings. Although construction from natural materials is already very old, it is nevertheless experiencing a resurgence.