How big a gain in house prices?

The Financial Times questioned the extent of house price gains in the UK.

It showed that while two of the house prices indices showed that house prices were now 10% ahead of their previous peak in 2008, the Halifax and Land Registry indexes showed them as about 5% below that 2008 level, leaving a large gap of 15% between their estimates. It said the different bases of the indices only partly explained the discrepancies, but reckoned a new index being developed by the Office of National Statistics might provide a more reliable guide.