Construction stocks were performing well on Friday with FTSE 100 building materials group CRH providing a lift to the sector.CRH, which manufacturers and distributed material products to the construction industry, was up nearly 4% in afternoon trade after JP Morgan Cazenove upgraded its rating on the stock from underweight to overweight.The company said on Wednesday that it had been notified by cement-maker Semapa of its intention to acquire CRH's shares in their joint venture, Secil. In 2004 CRH bought the stake for €429m euros, but Semapa has exercised its option to purchase the stake back for €574m. In 2011, Secil generated earnings before interest, tax, depreciation and amortisation of €102m on sales of €507m. Net debt at 31 December 2011 amounted to €142 million. Other stocks in the sector making gains were Balfour Beatty, Keller, and Prosperity Minerals.Top performing sectors so far todayConstruction & Materials 3,469.65 +3.43%Industrial Metals & Mining 3,906.11 +3.21%Financial Services 5,040.59 +2.29%Forestry & Paper 6,252.77 +2.20%Real Estate Investment Trusts 1,966.17 +1.98%Bottom performing sectors so far todayFixed Line Telecommunications 2,434.58 -1.38%Food Producers & Processors 5,611.14 -0.86%Mobile Telecommunications 3,954.41 -0.73%Tobacco 36,524.03 -0.15%Household Goods & Home Construction 7,156.49 -0.13%BC