Some floors have been replaced & insulated on a room by room basis.
In the study, 150 mm Celotex was fixed between the joists by removing the floorboards, attaching battens beneath the joists, and resting the insulation boards on top. Above that, Michael and Mo put down a bamboo flooring over a 15mm chipboard subfloor.
The lounge floor was a bigger job, because of the need to adjust the levels to make space for under-floor heating. First the floor and joists were removed. Then the new joists were put in, but at a lower level. 150mm of Celotex (supplied by Westville) was put down between the joists and held up by battens. Above that is 18mm chipboard and then 15mm of thermaboard. This thermaboard has tracks cut into it for the under-floor heating pipes, and it also acts as a heat store. On top of that is 16mm of engineered oak flooring.
The old fireplace was replaced at the same time, and is used very occasionally. Most of the time only the under-floor heating is used and Michael and Mo are very pleased with it.
The dining room awaits similar treatment.
Most of the original lighting has been replaced with LEDs and compact fluorescent lights. The old halogen lights caused problems in the bathroom and kitchen by sucking the moist air up through the fittings in the ceiling and creating a damp problem in the spaces above. In the loft above the main bathroom the excess moisture rising from the bathroom resulted in ice on the joists in the recent extreme winters. Additional ventilation vents to the loft space have been now fitted in order to reduce this effect.