Hi,
I have had a new extension built. It is single storey one bedroom. The inner skin of the wall is built with blocks and mortar. The builder did not put enough cement in the mortar and it is so crumbly I can easily poke it out and there are gaps . What should I do? I could poke it all out to a depth of an inch or so and re point the whole lot with better cement. Is it necessary? would it help anything? the roof and windows and second skin wall etc is all finished. Just about to put up the plaster board.Advice very welcome!!!