At todays prices, depending on what fuel you use by installing D/G you can expect to save around £75 to £150 a year but if you take into consideration annual price increases it will be considerably less over the long term.
So if your D/G cost you £1800 to install it will take more than twenty years to pay for itself, so purely as a financial investment its not brilliant, although it may help to resell your unit when the time comes.
Fitting heavy curtains like Phil suggested will insulate against the cold and will certainly help make a difference.
However, D/G has other possible benefits, like reducing condensation, but there are no guarantees with this.
Increased security, outside noise reduction, less maintenance and more comfortable living are all definite pluses.
I hope all goes well with your installation and you benefit from positive results.
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Tuesday, 6 December 2011