Describes a technique developed for measuring air flows between internal spaces of houses. Involves using a portable gas chromatograph to monitor the concentrations of three tracer gases released in three distinct zones within the building envelope. Using the results of each measurement, which takes approximately two hours, the ventilation rate of each zone can be calculated along with the interconnecting air flow. Presents the tracer gas equations involved, and includes an account of the experimental method and the practical difficulties encountered.
Discusses the use of a regenerative, air-to-air, rotary heat exchanger as part of a controlled ventilation system in a modern tightly built house. Describes analytical studies and the construction of a prototype. A four-month trial ina test-house indicated that the unit would be capable of recovering 5000 Kw/hof waste energy if operations were extended over the full heating system.
Gives measurements of the ventilation as well as the temperature efficiency of mechanical supply and exhaust systems (balanced systems). The ventilation efficiency is a measure of the performance of providing air in the occupied zone and is also an indicator of the air quality. The temperature efficiency is a measure of the system's capability of supplying heat in the occupied zone. Monitors ventilation efficiencies by adopting tracer decay techniques and the temperature efficiencies by measuring the stationary temperatures.
Reports measurements on air transport through homes made by a committee working a Dutch Standard on Heating Load Calculation similar to DIN 4701, but taking account of air infiltration losses through joints and cracks between glazing, window-frame and facade construction. Describes the measuring method applied. Tables air leakage coefficients c and flow exponents, n ,of a number of flats and single family houses. Also tables c and n values of cracks according to type of construction and material, use of weather strips and measuring institute.
Describes methods of measuring the three-dimensional flow field using a three-sensor hot-wire probe, with emphasis on the techniques developed by the author's group at the Pennsylvania State University. The hot-wire equations, data processing procedure, calibration techniques, and a discussion of various errors in the measurement are included. Some typical data acquired by thisprobe is also included.
Describes an energy audit being developed at LBL to determine economically optimal retrofits for residential buildings, based on actual, on-site measurements of key indices of the house. Measurements are analyzed on a microprocessor and retrofit combinations compatible with minimum life-cycle cost and occupant preferences are then determined. An important element of this audit is its treatment of infiltration.
Reports on the Swedish Energy Saving Survey of 1980, which produced two kinds of estimates on the effects of a number of energy conservation measures:< 1. Theoretical estimates based on simple degree-day models.< 2. Empirical estimates based on the amount of savings actually obtained in a house after retrofitting.< Compares the two methods of estimation, which shows the limitations of the theoretical estimates.
Reports on continuous energy measurements carried out in 6 detached single-family, low-energy houses in Copenhagen. Describes a few typical construction details to illustrate solutions to the problem of cold bridges, and to demonstrate ways of obtaining airtight constructions. Measures air change rate using tracer gas decay method and pressurisation and suction tests. Works out total heat loss for a period when ventilation systems are sealed and the houses heated by electric resistance heaters.
Shows the development of a procedure at Princeton University which involves an instrumented energy audit combined with a partial retrofit, and especially applicable to post-war single-family housing. This procedure is known as the `house-doctor' approach and is being tested in a 168 house experiment. Preliminary results show a 10-15% reduction in total use of natural gas following partial retrofit measures. Further retrofits based on house doctor observations led to a 20-25% reduction.