I turned down the offer of free external wall insulation under the government's green energy scheme. I'd had trouble with 3rd party contractors in the past and I'd seen the ones they were using on my road. They weren't even wearing the correct protective clothing.
I've just heard on Radio 4 that 98% of homes insulated under this scheme have potential problems with damp. The work was either substandard or the insulation wasn't appropriate for the property.