Persimmon achieved record profits in the first half of 2007 and is confident demand for new housing will continue despite stock market turmoil. In an interim statement the housebuilder announced record pre-tax profits of £281.1 million, a 9.8% increase. Completions were down to 8,002 from 8,226 but forward sales are at £1.35 billion and its landbank has increased to 82,145 …