To prepare for a switch away from gas to potentially less efficient heating, start with loft insulation, draughtproofing and double glazing.

He says that the experience could have turned into an ordeal had it not been for an endless supply of fresh coffee and the school's efficient heating system.

Attention should be paid to sound reduction and efficient heating.

These modified fireplaces are often equipped with a large fire window, enabling an efficient heating process in two phases.

Unlike the common coal gas, or coke gas which was used in municipal service, this gas provided a more efficient heating fuel.