Measurements of the airtightness of blocks of flats in Lithuania were carried out between 1995 and 1997 to assess the effectiveness of energy saving measures. At that time there was no real data on the airtightness of such dwellings available. The aim of the measurements was to evaluate how much heat could be saved by diminishing the air change rate. Since there are no thermostats installed in the dwellings, 'tightening' becomes the only measure available to increase indoor temperature.
Two-dimensional numerical simulations have been undertaken for the steady turbulent fluid flow in a room containing a fume cupboard which is attached to a wall and a ventilation duct which is situated in the ceiling of the room, see figure 1. The wall opposite to the fume cupboard is assumed to be porous and a fully developed fluid velocity profile is applied far upstream. The calculated flow is considered to be that which is actually found in the central plane of a practical fume cupboard.
Windows and doors currently 'use' more energy than any other building component. The cost of heat lost through a window over the lifetime of its use in a building is greater than the purchase cost. Energy and money can be saved, and greenhouse gases reduced, by choosing energy efficient windows.
Much has been said recently about healthy home environments. For many years anecdotal evidence has been collected about the improved health that residents in R-2000 homes have experienced. CW/Chas been promoting healthy home environment ideas through their Healthy House initiative. But is there scientific evidence behind claims that R-2000 homes are healthier for their occupants?
This study compares the characteristics of two tracer gases - sulphur hexafluoride (SF 6), and nitrous oxide (N20) – whose densities are different from that of air (i.e. 5.11 and 1.53, respectively). The study is based on exclusively experimental work; and concerns the behaviour of the two gases with regard to their distribution and dispersion in an experimental cell, incorporating into the comparison method an index that is intended to characterise the ventilation of an enclosed space, namely ventilation etfectiveness,