In order to investigate the possibilities of installing heat recovery equipment in old apartment houses, a large project has been started. There are 30,000 to 35,000 apartment houses in Finland with an average volume of6000-7000 cu.m. Possible savings from heat recovery in houses with mechanical exhaust are the transfer of heat to supply air using standard equipment and heat recovery from exhaust air using heat pumps.

Notes that if the exhaust air flows in an apartment building are adjusted to the same value in similar apartments, the pressure conditions may not be the same in these apartments. 

A fair comparison of ventilation systems is almost an impossible achievement. Even an economic comparison causes difficulties; the different systems render different room air qualities which cannot be counted in money. 

Reports the development of a small air-to-air rotary heat exchanger for residential applications in progress at Ontario Hydro Ltd. A prototype has been constructed and tested. Gives results of performance tests and the results of a numerical model for the solution of heat transfer equations as related to the prototype performance. States exchanger will be installed in aHUDAC conservation house.

Briefly describes a heat exchanger designed for use in a tight, solar heated house. The exchanger consists of three 3in. galvanized steel ducts within an 8in. galvanized steel duct. The ducts can be assembled in any length - 33 ft. was used in Provident House, giving a theoretical effectiveness of 33%.

The proceedings of the Canada Mortgage and Housing Corporation industry/science seminar "Controlled Ventilation with Exhaust Air Heat Recovery for Canadian Housing" 26 October 1978

A short note giving formulae for the design of spires for use in simulating the planetary boundary layer. Gives expressions for the height and base length of triangular spires which will produce given values of the boundary layer thickness and power-law exponent. Gives comparisons of calculated values with experimental data.

Describes a covariance integration method for the determination of fluctuating overall structural loads due to wind and their effects on low rise buildings. The required aerodynamic information can be obtained from boundary-layer wind tunnel tests: static structural influence coefficients are also required. Themethod is an alternative to the direct on-line weighting technique, but is less demanding on wind tunnel instrumentation and data acquisition facilities. To obtain peak values, Gaussian probability distributions have been assumedfor the loads or their effects.

Gives a brief historical review of the development of wind engineering as a discipline. Discusses the simulation of wind loads on buildings, the development of boundary layer wind tunnels and problems in modelling the natural wind. Describes modelling of the aerolastic behaviour of buildings andof stack gas diffusion. Describes instrumentation and measurement techniques. Indicates areas requiring further development.

Reports results of measurements of radon gas made in each of the Saskatoon low energy houses in December 1980. Finds that gas levels were higher in basements than on the ground floor but that concentrations of radon were not high enough to constitute a health risk. Suggests that permeability of basement walls may have a great effect on radon concentration and that sealing a basement may reduce levels.