Mick Wallace (Wexford, Independent) | Oireachtas source

An extraordinary number of houses in the country have been built with 9 in. cavity walls. Such a cavity can carry damp across. The outside walls may be pebble-dashed, but it makes such a difference to those houses if a 30 mm baton is introduced on the inside, with insulation and a new slab over it.

It is possible to paint over the slab. If a builder does it properly it makes the house far more snug. A 9 in. cavity was not designed to keep out the moisture or cold, yet an extraordinary number of houses have been built with 9 in. cavities. They were still at it right up to the end of the 1980s.

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