residential

The Net Zero Energy Residential Test Facility (NZERTF) was constructed at the National Institute of Standards and Technology (NIST) to support the development and adoption of cost-effective net zero energy designs and technologies. Key design objectives included providing occupant health and comfort through adequate ventilation and reduced indoor contaminant sources.

Sizing rules in residential ventilation standards lack uniformity in both methodology and resulting design flow rates. Additionally, mere comparison of design flow rates is case sensitive and, due to effects of infiltration, adventitious ventilation and occupancy, ill-suited to assess performance of an exhaust ventilation system with regard to the achieved indoor air quality and energy cost in terms of heat loss.

Sizing rules in residential ventilation standards lack uniformity in both methodology and resulting design flow rates. In order to investigate the best achievable performance of natural ventilation, exhaust and fully mechanical ventilation systems, this paper presents a multi-zone simulation based optimization study for both a detached dwelling.

The airtightness of 36 houses built since 1995 and across four cities in New Zealand (NZ) was measured. In a subset of 31 of these homes, the average ventilation rate was measured over several weeks in the winter using a perfluorocarbon tracer technique (PFT). These results can be added to earlier airtightness data to provide a platform for improving the air quality and energy efficiency of residential ventilation in NZ.

It is widely accepted that ventilation is critical for providing good indoor air quality (IAQ) in homes. However, the definition of "good" IAQ, and the most effective, energy efficient methods for delivering it are still matters of research and debate. This paper presents the results of work done at the Lawrence Berkeley National Lab to identify the air pollutants that drive the need for ventilation as part of a larger effort to develop a health-based ventilation standard.

A retrofit study was conducted in an unoccupied manufactured house to investigate the impacts of airtightening on ventilation rates and energy consumption. This report describes the retrofits and the results of the pre- and post-retrofit assessment of building airtightness, ventilation, and energy use. Building envelope and air distribution systems airtightness were measured using fan pressurization. Air change rates were measured continuously using the tracer gas decay technique.

As part of a field measurement project of unvented gas fireplaces in 30 homes, portable carbon monoxide sensors were located in several places in each home. This was done to assess the degree to which combustion by-products became distributed throughout the home. The sensors indicated that carbon monoxide levels began rising throughout the home almost immediately, at or near the one-minute sampling interval. The results show that, on average, the reading in the middle of the fireplace room was about 95% of the reading at the mantel.

Indentifying pollutants that pose a potential hazard indoors is an important first step to reducing risks. We reviewed key published studies reporting measurements of chemical pollutants in residences. Summary results were compiled and used to calculate representative mid-range and upper-bound concentrations relevant to chronic exposures for over 300 pollutants and peak concentrations relevant to acute exposures for a few episodic activity-associated pollutants.

For residential forced air heating and cooling systems conventional thinking is that air supply registers should be located under exterior windows. There were good reasons for this in the past (primarily to counteract the cold downdraught from the window) but new construction standards (well-insulated walls, better glazing and air tight wall/window interface) mean that there is now less downdraught. Positioning the supply air register away from a window could have a large impact for new construction as duct lengths could be shortened (saving materials and construction time).

Living room winter temperatures are explored using data from 397 randomly selectedhouses from the Household Energy End-use Project (HEEP). HEEP has collected energyand temperature data on a statistically representative sample of New Zealand houses(Latitudes 35S46S). Initial analysis of the winter (June-August) living roomtemperatures shows that heating type, climate, and house age are important drivers ofindoor temperatures. On average, houses heated by solid fuel are the warmest, withhouses heated by portable LPG and electric heaters the coldest.