I have just had a survey to assess part of my house for cavity wall insulation. My house is in two parts; the original house and a large extension. The original part has been insulated by the previous owners. I was seeking to fill the cavity in the newer part which isn't insulated. The man walked around the new part and noted the ventilator on the outside which was part of the build ince there is a "flame-effect" fire in there. "Not big enough", he said, "It must be enlarged to about a square foot cross-section". He went on around the house and noted that we have an open fire in the older, already insulated, part. "We'll have to put a ventilator into this room, too" he said, "there should be one in that room too" I suggested that I hadn't asked him to look at the rest of the house which was insulated and he said it was the law. I suggested that he should partake in some "Sex & Travel".
So the questions are:
- What are the rules about ventilation when a cavity is filled?
- If the filling reduces air flow to such fires, how does air percolate today? Through the plastered walls or up thru' the concrete floor?
- What are the rules about retro-fitting old parts of a house to newer standards? E.G If I had new wiring in part of my house it would be Brown/Blue. By the same logic as the cavity wall person applied, the electrician might insist on ripping all the older red/black wire in the older parts not being upgraded..patently daft.