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To do this, we selected CONTAM, a program developed by the National Institute for aluminium Standards replacement and Technology and available flee through its Web site (see information windows at the end of this article). CONTAM calculates instantaneous values of air flow through openings in buildings, using the flow characteristics of each opening, orientation, height, and other factors, based on a aluminium weather file that provides temperature and wind replacement information. We set up our CONTAM runs to calculate air flow for each hour of the typical year, and then summarized the results by month.To complete the energy simulation inputs, windows we gathered information on building envelope construction and estimated appliance loads, hot water usage, and occupancy for each unit type. Water-to-air heat pumps installed in each unit provide aluminium heating and replacement cooling at McLean Gardens. Six central plants equipped with boilers windows and aluminium and cooling towers provide conditioned water at roughly 70[degrees]F replacement to the heat windows pumps as a source or sink for energy. We took advantage of Visual DOE''s ability to model this system by grouping an upper, middle, aluminium and lower unit together with a central plant for each analysis. Comfort. replacement Window replacement at McLean windows Gardens aluminium and replacement would result in reduced window air leakage and increased wintertime temperatures at the inner windows glass surface. aluminium Reduced air leakage means fewer drafts near windows. Increased replacement wintertime glass temperature would reduce cold convection currents windows that aluminium spill off windows, further reducing the sensation of drafts. The temperature increase would also increase the average radiant temperature of replacement the indoor environment. (Average radiant temperature has nearly as strong an influence on comfort as does air temperature.) While windows all the replacement options would yield some increase in temperature, the higher-performance low-e, argon-filled glass would offer the greatest increase. While improved comfort has value in itself, it may also result in thermostat adjustments that yield additional real energy savings. Cleaning. The existing window system is almost impossible to clean thoroughly from inside the building. As a result, many residents pay for professional cleaning, at a cost of $100 or more, once or twice a year. Tilt-in replacement windows, and elimination of the separate storms, would allow relatively easy cleaning of all surfaces from the interior. Thus, residents who drop professional cleaning in favor of doing it themselves, and consider it a free-time activity, might save more in cleaning costs than in energy costs.Ventilation. Although the McLean Gardens buildings don''t have mechanical ventilation systems, reports of excess moisture accumulation and mold growth are uncommon. The leaky windows are undoubtedly a major factor in providing natural ventilation rates sufficient to limit moisture accumulation during cold weather. (Air conditioning limits moisture accumulation during the summer.) aluminium and replacement Window windows replacement would significantly reduce overall building infiltration. Our project did not include measurement of overall building leakage, but we believe aluminium that overall natural infiltration rates would be cut by more than 50%, and that the resultant increase in interior humidity and replacement condensation would probably cause paint failure windows and mold growth in some units. This issue could be addressed directly through the installation of mechanical ventilation systems. The risk of excess moisture accumulation and the cost and complexity of installing a ventilation system are significant factors to be weighed in planning window replacement.
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