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The water damage in buildings because of leaking pipes and increasingly because of floods and severe weather require professional help. Methods for improved repair and remediation techniques have to be developed. The water damage in buildings because of leaking pipes and increasingly because of floods and severe weather require professional help. Methods for improved repair and remediation techniques have to be developed. The paper aims to discuss these issues.

Therefore, large scale laboratory tests with four rooms, each with three types of masonry walls (Figure 2 and Plate 1) and typical floors for intermediate storeys with insulation were performed within a climate simulator. Artificial water damage was provoked through watering the floors, and the dispersion of water in the floors and the rising damp in the walls was measured. In the follow-up to the watering of the floors, a company specialized in drying wet buildings, installed systems for under floor drying and wall drying.

The drying process of the different components and layers of the floor construction and walls was monitored by a measuring system with more than 300 sensors for moisture content, relative humidity and temperature accompanied by thermography and demonstrated so the advantages and disadvantages of the different tested drying systems. After providing an initial contamination that is typical for construction sites, the microbial load (mould infestation) within the wet components was monitored at different times by experienced biologists. So after three weeks under floor drying no mould growth could be asserted but more bacteria than expected were found.

The aim of the research was to gain more confidence in selecting appropriate drying procedures and systems in order to identify the right moment for terminating the drying process. A further intent was to acquire data for computer simulations.

Decreasing energy demand due to improved building standards requires the development of new biomass combustion technologies to be able to provide individual biomass heating solutions. The purpose of this paper is, therefore, the development of a pellet water heating stove with minimal emission at high thermal efficiency.

The single components of a 10 kW water heating pellet stove are analysed and partly redesigned considering the latest scientific findings and experimental know‐how in combustion engineering. The outcome of this development is a 12 kW prototype which is subsequently down‐scaled to a 6 kW prototype. Finally, the results of the development are evaluated by testing of an accredited institute.

Based on an existing pellet water heating stove, the total excess air ratio was reduced, a strict air staging was implemented and the fuel supply was homogenized. All three measures improved the operating performance regarding emissions and thermal efficiency. The evaluation of the development process showed that the CO emissions are reduced by over 90 per cent during full load and by 30‐60 per cent during minimum load conditions. Emissions of particulate matter are reduced by 70 per cent and the thermal efficiency increased to 95 per cent.

The result represents a new state of technology in this sector for minimal emissions and maximal thermal efficiency, which surpasses the directives of the Eco label “UZ37” in Austria and “Blauer Engel” in Germany, which are amongst the most stringent performance requirements in the European Union. Hence this design possesses a high potential as heating solution for low and passive energy houses.