A spokesman for the bank said details were still being worked out but it would "include at a minimum always discussing with buyers if they've checked the contamination status before proceeding". Other more formal checks might be considered, he said.

ME is just one of the banks caught up in the Mr Fluffy crisis, with people unable to follow though on commitments to buy a house because at least some banks are not lending on Mr Fluffy homes.

Buyers and sellers are reluctant to speak publicly about the situation, but it is clear that some have been caught up in disputes about whether the Mr Fluffy status was properly disclosed and whether buyers can secure loans to follow through.

About 22 Mr Fluffy homes have been sold since the February 18 letter this year which sparked the crisis.

The spokesman for ME Bank said it sympathised with owners in a difficult situation and it urged governments to resolve the situation as quickly as possible to provide certainty.

St George Bank, asked how it was dealing with customers on the issue, would say only that each loan was considered on a case-by-case basis.

The Commonwealth Bank said it lent money on each property according to security and that properties "must be readily saleable".

It would not elaborate, but it appears Mr Fluffy homes would not pass the risk test.

The news that the crisis has extended to mortgages comes as the ACT government confirmed that, in the first seven days of allowing former tenants and owners access to information about Mr Fluffy homes, it had processed 113 requests from people concerned they might have lived in an affected home.

Of those, five had come back positive. The five were from a former tenant, two former owners, an existing owner and the adult child of an existing owner.