People who live in listed properties or in areas of conservation have been advised against fitting plastic windows as it can spoil the look and feel of a house.
However, the Heritage Trust has noted that there are still ways such
people can increase their energy efficiency.
Speaking to the BBC, Chris Wood, head of building conservation and research at English Heritage, advised homeowners who were carrying out renovation work on their properties to use the appropriate materials.
However, this does not mean that energy efficiency has to take a back seat.
The Heritage Trust claims that windows can be draught stripped or secondary glazing can be added inside the existing windows to reduce heat loss.
Furthermore, putting up curtains made of thick material and closing them in cold weather can also act as a form of secondary glazing, the group notes.
And for Britons living in more modern housing, the Energy Saving Trust advises that double glazing could
see £135 a year being saved on gas and electricity bills.
