The share price of plumbing-supplies merchant Wolseley has been disappearing down the plughole since June, as the group has been hit by the double whammy of a weak dollar and a slowdown in the US housing market.

However, the chairman and the chief executive did their bit to support it this week, as each spent close to £125,000 increasing their stakes.

Chairman John Whybrow bought 15,000 shares at 825p to take his holding up to 85,284, while chief executive officer “Chip” Hornsby bought 15,429 at 804.5p to take his holding to 83,795.

The company reported a 7.3% drop in full-year profit before tax and exceptional items on Monday and said it is too early to say whether “less favourable” sales trends are likely to continue.

Profit before tax and amortisation and impairment of acquired intangibles fell to £758m in the 12 months to July 31 from £817m a year ago.

The company blamed the impact of the difficult American housing market, falling lumber and panel prices and the weakness of the dollar.

- Sir Ian Gibson, the nonexecutive deputy chairman of Wm Morrison, has bought his first shares in the supermarket retailer.

Gibson, who will take over as chairman from founder Ken Morrison next March, bought 108,055 shares at 276p each. The group recently reported sharply higher interim pretax profits at £266.3m, from £134.2m previously. The company is confident of achieving its profit expectations for the year.

Directors have in-depth knowledge of their businesses, so it can pay to track their moves. Every week Digitallook.com reveals the bosses who have bought or sold big stakes.