This research deals with determining the acoustic attenuation of heating, ventilation, and air conditioning (HVAC) ductwork. A finite element approach was developed for calculating insertion loss and breakout transmission loss. Procedures for simulating the source and receiving rooms were developed and the effect of structureborne flanking was included. Simulation results have been compared with measurements from the literature and the agreement is very good. With a good model in place, the work was extended in three ways. 1) Since measurements on full-scale equipment are difficult, scale modeling rules were developed and validated. 2) Two different numerical approaches were developed for evaluating the transmission loss of silencers taking into account the effect of higher order modes. 3) A power transfer matrix approach was developed to assess the acoustic performance of several duct components connected in series.

The aim of this master thesis is to design a seven-storey office building in Hodonín, Czechia. The building has retail spaces in the basement and first floor and offices in second to sixth floors and utility room and elevator engine room in the seventh floor. Individual floors are accessible via stairs and elevator. The vertical load-bearing structure consists of reinforced concrete walls and columns. Horizontal load-bearing structure consists of cast-in-place reinforced concrete slabs. The roof is flat with photovoltaic power plant connected to main battery. The main source of heating energy for the building is a heat pump (air-water) backed by a secondary electric boiler. Fresh air is supplied by a HVAC unit installed on the roof. Overheating due to solar heat gains and equipment is mitigated by local AC ceiling units. Automated roller blinds reacting to solar gains and glare are installed over the windows. The next part of thesis consists of comparison of pressure properties of sheet metal duct and CLIMAVER system.