Hello. Many thanks. It all turned out very well. I used a Festival Ale Kit (Golden Stag) and it really is very nice beer. It's a very fruity beer - although VERY lively (plenty of carbonation).
Thank you for the reassurance. My beer has been fermenting for around three weeks (without assistance). Obviously, the ambient temperature has risen greatly - the room is now 21 degrees.
This idea sounds just what I'm looking for - as my kitchen is a little too cool just now.
The heaters seem to be anywhere from 25w to 500w. Are you able to give a rough idea of a suitable power rating? Many thanks, Stephen.