When I bought my current bike, I actually inflated the cost to my wife by £300, so that I could also buy a Wahoo bike computer at the same time The bike was actually £2100, I told her £2400.
Not sure I follow your maths?
You don't say what type of house that quote was for, but even if it were for a detached, it is just less than a 3 fold increase, from £170 to £500.
If the quote was for a terraced house, then it is less than 10% increase.
My savings are only about half the figures quoted by Which, only the downstairs wall has a cavity, upstairs is solid. They don't charge any less for insulating only half the house though.Duh!. I was looking at the wrong numbers. I was looking at the bill savings, rather than the installation costs.
Mine's a semi.The instalation cost from the Which article suggests £3,945-£4,930 for a detached house?
I wouldn't put too much weight behind any figures from Which. Local quotes for I stallation would probably be around 25-30% lower.