The presented review has been devoted to the problem of volume-determined properties relaxation of silicate glasses at room temperature. It is shown that the experimental data are described by the simple Debye exponential law or by a superposition of two exponents. Their parameters are calculated and systematized. A molecular-kinetic model is proposed for these ageing processes. It proceeds from the possibility of volume relaxation due to the cooperative beta-relaxation mechanism with no change in the system's topology. The characteristic ageing times can be calculated according to equations obtained based on the viscosity data in the glass transition range. The precision of the calculations is about (+-)15% at the time variations from a new weeks up to about 15 years. The system of calculated parameter is proposed which characterizes the completeness of ageing and its rate at any glass age. Optical and thermometric glasses have been ranked by their tendency to ageing. The scheme of future investigations predetermined by practice is defined.
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