To Russia With Blower Doors

Russia may soon be the scene of one of the world's largest building energy retrofit projects, designed by the Russian government with support from the World Bank and other agencies.

Thousands of apartment buildings were constructed across Russia during the Soviet era, when energy was thought to be almost free, due to the seemingly limitless natural resources of the region and a system of allocating economic resources that was generous to the energy production sector. Now that Russian energy prices are rising to world levels, these buildings are very expensive to heat.

In the Soviet era, a "company town" was built and run by each enterprise to house and provide the basic social needs of its workers and their dependents. Enterprises paid for all utilities, including energy, which accounts for over half of the costs for operation and maintenance. Enterprises are now required to divest "social assets," such as housing, to municipalities. However, rising costs of operation, especially energy costs, are a major disincentive for cities to accept the housing. Although a timetable exists for raising residential tariffs to recover 100% of the energy costs, the cities now spend much of their budgets subsidizing housing maintenance and utility costs.

To address this problem, the U.S. Department of Energy supported a study last fall of the potential for efficiency improvements in Russian multifamily buildings. From this initial effort, the Russian Ministry of Economy, with financing from the U.S. Trade and Development Agency, contracted Battelle Pacific Northwest Laboratories to develop a retrofit strategy. In April 1995, Battelle formed a team of energy experts to collect data from a representative set of apartment buildings in the Moscow suburb of Zhukovskij. This international team consisted of engineers from Battelle; Infiltec; the Center for Energy Efficiency in Moscow; the Institute of Building Physics in Moscow; and IVO-Group in Tallinn, Estonia, and Helsinki, Finland.

Three buildings and a heat substation were instrumented to begin long-term monitoring of energy and water use as well as indoor and outdoor conditions. Short-term tests included wall U-value determinations at about 40 locations in 11 apartments. The bulk of the team's activity, however, focused on blower door testing of 50 occupied apartments.

Tens of thousands of Russian apartments have been mass-produced since World War II using a few standard designs. The Zhukovskij blower door testing involved standard 14-story, nine-story, and five-story buildings. In these designs a typical one-bedroom apartment contains a kitchen, a bathroom, and one sleeping-living room, totaling about 33.5 m2 (360 ft2). A typical 54-m2 (580-ft2) two-bedroom apartment has an additional sleeping-living room, and a typical 73-m2 (790-ft2) three-bedroom apartment has two additional sleeping-living rooms. Most of the common areas, such as the lobby, stairwells, halls, and elevators, are poorly maintained and barely lit, but the apartments are comfortably furnished.

The buildings tested in Zhukovskij were all constructed of precast concrete panels. In this type of building, there are many joints that must be sealed after the panels are lifted into place. There are no insulation cavities in the side walls of the Zhukovskij buildings, so the total wall insulation value is provided by the 14-in thick exterior concrete panels. Our heat flux measurements from Zhukovskij showed that the effective R-value was about R-3, as expected for 100-lb/ft3 concrete. All windows are wooden casement, double-pane, with no effective weatherstripping; windows cover over 16% of the total wall area and represent about 10% of the apartment floor area. Apartments in regions further north than Moscow are reported to have triple-pane windows. To combat drafts, most of the residents use foam rubber, newspaper, or tape to seal up their windows around October 15 each year. They unseal them around April 15.

Heating is provided by radiators located below each window. The radiators receive hot water through an extensive distribution system from a central district heating plant. Apartments generally do not have individual controls or metering, and these cannot be easily added because radiators are typically plumbed vertically in series. Heat delivery is controlled by varying the hot-water supply temperature at the central plant according to daily ambient temperature. Ventilation is driven by a passive vent chimney system with separate vents in the kitchen and bath-toilet. This type of system must provide excess ventilation in cold weather in order to create adequate ventilation in moderately cool weather. The Russian building experts said that the design air change rate induced by the pre-1985 passive ventilation system was four air changes per hour (ACH) when the outside temperature was -28deg.C (-18deg.F)! The building code of 1985, which calls for 0.8 ACH at 5deg.C (41deg.F), will still result in 2 ACH at -28deg.C.

During a typical day at Zhukovskij, three separate blower door teams each tested two or three apartments. Each team had at least one Russian speaker so we could ask apartment occupants about ventilation and comfort issues. At each apartment, we took three blower door measurements: leakage as is, leakage with the ventilation ducts sealed, and leakage with the ducts sealed and all the window and door cracks sealed with masking tape. This sequence led to the discovery of ventilation problems (some vents were completely blocked) and provided estimates of the leakiness of the windows and apartment envelope.

The next phase of the project is to analyze the measurement data, model the heat loss and ventilation rates, and determine the cost-effectiveness of retrofit strategies. Some retrofits with high potential energy savings, such as installation of exterior wall insulation or wholesale replacement of windows, may not be feasible based on domestic fuel prices, which will have to be estimated over the time frame of the analysis. Preliminary results suggest that life cycle cost-effective retrofits may include

• Modifying the passive stack ventilation system to reduce the flow during low-temperature periods.
• Installing effective permanent window and door weatherstripping.
• Reducing stack-induced infiltration by repairing or weatherstripping access doors, dampers, and panels, and by sealing around conduits that provide leakage paths to stairwells, elevator shafts, garbage chutes, smoke exhaust risers, and electrical and plumbing risers.
• Adding attic and crawlspace insulation.
• Controlling heat delivery at the distribution substation level, at the building level, or possibly within buildings at the perimeter radiator risers or individual radiators.
• Repairing leaks and insulating distribution piping.
• Installing low-flow plumbing fixtures.

Installing a more comprehensive and equitable energy metering and cost-allocating (billing) system, though not an efficiency measure in the strict sense, is also expected to yield cost-effective energy savings (see "The Best Boiler and Water Heating Retrofits," p. 27).

We plan to make measurements in more Russian cities before next winter, and to install some retrofits in selected buildings so that their performance can be monitored over the winter. Large-scale installation of efficiency measures will begin once the true costs and performance of retrofits have been demonstrated. The World Bank expects to finance about two-thirds of the cost of retrofitting up to half a million dwelling units (about seven thousand apartment buildings) in six Russian cities.

David Saum is president of Infiltec, Peter Armstrong is senior research engineer at Battelle Pacific Northwest Laboratories, and Yurij Matrosov is leading researcher with the Center for Energy Efficiency and the Institute for Building Physics, both in Moscow.