This paper is based on the results of theoretical and implementation work in the development of mechanical connections with steel plates and steel elements in timber structures. The analysis of the slip of joints and support details ranks among important issues from the point of view of designing timber structures. The influence of joint stiffness on structural behaviour should be considered in modelling assumptions.
In January I published an article about the upcoming revision of CSN 73 0540-2 Thermal protection of buildings, Part 2: Requirements. I expressed to changes in each individual chapter. Since then there is new development in the standard revision. Some comments by members of the Standardisation Committee No. 43 and by professionals from the April public consultation of the standard were implemented. Some chapters of the standard are nearly unchanged since January, but some have changed in fairly major way.
Much has been written about this Moravian Village at the foot of the White Carpathian Mountains. It is renown for its environmental projects, it has been visited by many prominent personalities and it is considered an example of energy saving and environmental construction. This time, we have focused on a passive house that works as a model of environmental projects in rural areas.
Wood pieces, even locally damaged exhibit useful stiffness and strength parameters with which they can help continue to meet current requirements - after repair. Experience with old wooden structures such as roofs of church towers demonstrate the ability of timber stored in a suitable environment to retain its material properties for many centuries.
The construction of a family house in a quiet spot in a village is a common request that should not surprise anyone. In the village of Mylsejovice, located in the Olomouc Region at 353m above sea level, there is an interestingly designed low energy house that has dealt with the use of the chimney, among other things. Originally, the owner didn't have in mind a passive house. The final measurements pleasantly surprised him.
One of the important functional properties of ETICS is the stability on the substructure after construction into the building. The paper deals with the CSN 73 2902, which specifies requirements for the design and use of ETICS, which consists thermal insulation boards made of expanded polystyrene or mineral wool.
Our serial continues with this low-energy house built with sand-lime bricks. This time, the family house is located not far from Liberec, in the foothills of the Jizera mountains. The surroundings, predominantly rural houses near a protected natural area, influenced the shape of the house. Its location responds primarily to the surrounding buildings and the slightly sloping land.
The less the knowledge, the better the (shown) results.“ This proverb should never be applied in Civil Engineering works, not even in the field of energy calculations of a building. The technical documentations should provide clear evaluation guidelines and, whenever possible, plenty of straightforward information. Thanks to the subsidy programs of the Czech Republic, which are finally being applied to passive buildings, the issue of energy calculations has suddenly become important for planners and the administrators of the programs. Refining the definition of zero-energy buildings will be a key issue in the near future. Zero energy buildings should be understood as a logical continuation of passive buildings, a reasonable addition to active energy components.
The paper describes the role and necessity of water in floor screeds and provides examples of damages caused by moisture. Water is an integral part of many of the widespread construction materials. However, in relation to floor toppings, it poses a risk to their durability. Recent examples show that floor damages caused by moisture are still a current issue. Partly due to the design of potentially hazardous structures and partly due to incorrect detail implementation or to the pressure to shorten necessary technological pauses.
While in Germany and Austria this kind of buildings are already a common sight, in the Czech Republic it was celebrated as a local pioneer. The calcium and sand structure with a gabled roof supported by glass rubble, which was certified by the Passivhausinstitut Dr Wofgang Feist y Darmstadt, has passed a wide range of technical measurements and numerous visits. We attended one of them.
Dry floors are among the proven and technically perfect materials of our times. The paper brings attention to the need to know about what should be below and above the structure. Only then these structures will be realised without mistakes by both designers and builders. The system of floor layers is an important link on the chain of fast, economical and modern building methods. It is important to know not only the structure, but also the composition and design of the dry flooring systems, the design solutions that use dry flooring elements and aim to improve the acoustic and technical thermal parameters of the floors.
Even though the use of skylight windows in passive houses is questionable, sometimes it can not be avoided. The increase in the number of energy efficient buildings has lead to an increase in the range of products aimed at this type of constructions. On our market there are several manufacturers that offer windows for passive buildings. Usually they are standard triple-glazed skylights supplemented by a so called thermal kit. If a manufacturer presents other parameters than just the value of the Ug coefficient of glazing, a lot of optimism will be needed for that to be believed. However, the underlying problems of the use of skylight windows in passive buildings will still remain.
Durability and functional reliability of buildings and structures of wood and wood based materials is significantly influenced by moisture content of these materials. In the article we report the results of measurement of moisture in the wood samples mounted between the outer walls with air chambers and comparing the measured values with values calculated by us in the recommended way of moisture balance in the construction according to ČSN 73 0540.
The hot-air treatment of the roof truss of the Upper Church in the village of Velká Lhota at Dačice is documented in stepwise details as a graphical and textual presentation with supporting charts and photographs. In addition to a mycological analysis, a project preparation plan and the main heat treatment technology, a detailed operations schedule is introduced as well as temperature measurement, supporting constructions and heat penetration. The writers’ utmost objectiveness towards this method is demonstrated by thermal camera images of the critical sites and cavities attacked by fungi. The article provides a comprehensive overview of application practices with all necessary recommendations, including the final application of chemical preservatives on the already heat-treated wooden framing.
The higher insulations standards for windows used in the construction of passive houses usually result in lower energy permeability of the glazing. Whether it is more efficient the use of triple or double glazing will depend on the orientation and shading of the windows, and will also be related to the characteristics of the whole building and the way it is used, specially the size of the internal gains. A study conducted on groups of apartment buildings, using multiple simulations, evaluates the impact of the properties of the glazing and the resulting heating needs for various conditions of shading, insulation and size of the internal gains.
Today, if a standard windows and doors consider single-frame windows and doors from plastic and aluminum profiles and wood “Euro” profile, non-standard, in terms of representation on the Czech market, include lining windows, skylights, interior doors and door frames, and light tubes. A very special par is fire resistant windows and fire resistant interior and exterior doors with declared reaction to fire, which are not the topic of the paper.
The paper is focused on some new types of timber structures made from solid timber, glued laminated timber and wood based materials. Especially glued laminated timber is a highly engineered material, because large sizes of structural members and the possibility of various shapes in beams, frames and arches are available. The analysis of intensive loaded structures with large spans shows clearly that to the most advantageous types of connections belong those made by means of steel elements. The analysis of the slip of joints and supports ranks among important issues in designing timber structures. The paper summarises some experience and conclusions from the construction of timber systems with steel-to-timber joints.
In 2007 the group GAIA SpA got an idea from Massimo Fiorini (an amateur builder) to reconstruct the delapidated Marconi Laboratories in Coltrano, near Pisa (Italy) and turn it into EneryPlus terraced passive houses. The group was fully convinced after a visit to the ASSA passive office building in Santa Croce Sull'Arno, and in 2008 they began the design works. The building turned out to be appropriate to be turned into a passive house project. However, the problem was listed in the highest heritage class, which had been granted not for the importance of the building itself, but as part of a listed group. The planning had to be very detailed. Another problem was the arched concrete roof, which was extremely vulnerable to collapse. The Heritage Protection Office in Pisa was at first very sceptical with the project, but in the end they were convinced about the interest and the quality of the project after a series of meetings with the builders and the representatives of TBZ.
