German

The current German Standard specifies a minimum thermal insulation. However even with excellent insulation, if the air change rate is too low, condensation can form. High humidity emissions in dwellings can require air change rates of more than 2/hour. The use of mechanical ventilation, possibly humidity-controlled and with a heat recovery system, is suggested to minimize ventilation heat losses. The user has to be educated to provide adequate ventilation in spring and autumn, but during the cold season the ventilation rate can be reduced to two thirds of the minimum value.

Presents a compact control system of modular construction, developed in the Netherlands, which incorporates in one unit the functions of air circulation and ventilation, heat recovery and heating. It conforms to the German health and building regulations and operates with any fuel. In 1983 it was installed in 6000 new, highly-insulated Dutch dwellings and in another 10000 dwellings in 1984. Operating costs are 700-800 florins/year for heating a living area of 110m2. Future models may include water heating.

Describes four ventilation options for a 3-4 person dwelling of 100-140 m2 living area. These are: a simple transverse system conforming to State (Land) building regulations, a shaft system conforming to Standard DIN 18017 (old design), a central heat recovery based system conforming to Standard VDI 2088, and a central heat recovery/heat pump system. Presents the energy balances of the four systems with the aid of energy flow diagrams.

Discusses the problems arising from inappropriate ventilation in highly-insulated flats and houses: outlines the advantages of ventilating systems with heat recovery as a possible solution. Deals with the advantages of combined ventilating and space heating installations including those which can blow air directly into bedrooms.

Discusses the various measures used to achieve the energy-conservation aims of the Federal Republic of Germany thermal insulation regulations of 1 January 1984 and to counter the health problems that arose as a result of higher fuel prices leading to reduced domestic fuel consumption in conjunction with poor ventilation. Discusses the advantages of installing heat recovery based central air conditioning systems with filters which are eligible for tax relief.

Presents a mathematical model for the measurement of thermal comfort. Compares the results with previous measurements of air velocity in buildings with and without air conditioning.

Describes qualitative experimental investigation of the air flow in a scale model representing a typical, average hall. Smoke was used to display the air flows. A mathematical model was also developed. Determination of the turbulent air flow in the model confirms the suitability of the mathematical model foruse in quantitative experiments, in particular for measuring the heat flux density.

Summarizes the factors affecting air infiltration, with definitions of the terminology used. Discusses minimum and optimum air change rate, and choice of ventilation system. Lists research in Switzerland.

Discusses the future prospects of domestic ventilation and whether mechanical ventilation will be necessary to satisfy requirements as windows become more airtight. Suggests use of centralized mechanical ventilation, with openable windows for summer ventilation.

Notes that the trend to airtight window constructions has upset the balance in buildings between moisture generation and its removal. Treats the factors which combine to determine whether a building will have moisture problems. Presents a procedure for the straightforward determination of the specific minimum air flow required in a particular building to prevent condensation on the inner surface of corners formed by two dimensional external walls. Determines the base air flow and the supplementary air flow for four models of representative apartments.