SIG, which distributes specialist building products in Europe, saw its underlying pre-tax profit in the first half fall as revenue declined on the effects of an extended winter and weak market conditions.Underlying pre-tax profit dropped to £30.2m from the prior year's £35.5m and revenue decreased to £1.27bn from £1.28bn. Underlying basic earnings per share fell to 3.5p from 4.2p.While sales in Mainland Europe benefited from the strengthening euro, revenues in continuing operations fell slightly, by 0.7% to £692.2m, with like-for-like sales down 4.5%.The group said it has taken prompt action to reduce its costs and expects a strong performance in the second half."While there are signs that market conditions are starting to improve in the UK, construction activity in Mainland Europe remains weak," according to Chief Executive Stuart Mitchell."With the improving sales trend and the group's prompt action to reduce costs, we continue to expect to make further progress in 2013 consistent with our previous expectations, assuming normal weather conditions in the second half."The company increased its interim dividend by 15% to 1.15p per share.