Get a heat pump drier. They are like 600W and will cost a quarter as much to run.
Going electric will cost you 4x as much - look at the comparative pence per kWHr.
I have an ASHP - R290 based with 24,000 kWhr per annum heating...
How are you doing “some cooling”?
Have a look at this: Free UK Span Table for Domestic Floor Joists to BS 5268-7.1 (C24, 1.5 kN/m² load) - Timber Beam Calculator
Do you have a BT line box as the master socket?
What is the size of the joist and what will be the span, with it removed. Is there any particular loads above it?
will the door be able to open?
I prefer them as the compression fittings always seem to come lose eventually.
Or even just push fit, depending on what pipe is coming out the wall.
I would however suggest getting a structural engineer round to look for the sake of £150 or whatever. What do building control want to see?
After nearly 15 years there would be signs of stress appearing if is wasn't adequately supported IMO. e.g. cracking in plaster/cove etc below...
Electric or wet? What is the floor construction currently?
“Adequate in use” then
How long has it been there
Does it have a DPC? And is the outside rendered?
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