A well constructed above-ground cellar or a well dug underground cellar will require the minimum of additional temperature control.
The position of your cellar or your climate may oblige you to introduce a cooling device. The introduction of a cooling unit into a constructed cellar will provide complete temperature stability. However, care must be taken with the placement of the unit to avoid uneven distribution of the cooling air.
Regard assembled wine as your best cooling block. A high density of wine bottles will reduce wine temperature fluctuations.
Consider keeping your long-term wines in a professional storage facility if your cellar cannot conform to the optimum temperature ranges.
A hygro thermometer will provide you with accurate information as to both the temperature and humidity ranges within your cellar.
This is just a sample of the information available in “How To Build Your Own Wine Cellar”!