Housebuilders dominate the mid-cap index Monday following bright news on the housing market.Mortgage lending leapt by 17% in June to £12.3bn, its highest since December, according to the Council of Mortgage Lenders (CML). The Bank of England said the six major banks approved 51,000 mortgages for house purchase in June versus 45,000 the month before. Gross mortgage lending rose to £9.2bn from £8.6bn.Meanwhile, property website Rightmove said the average asking price for a property in England and Wales jumped 0.6%, more than £1,400, this month as buyers chased a decreasing number of bargains.Taylor Wimpey, Barratt Developments, Bovis Homes and Bellway have enjoyed the biggest gains on Monday.Earlier this month, Merrill Lynch said many of the big names in the sector are undervalued and trading on a "worst case scenario" basis.Investors also placed orders for shares in Domino's Pizza which thanked heavy price promotions for lifting sales in the half year to 26 June by 15% to £196.4m. Pre-tax profits jumped 25% to £13.6m and the dividend leapt 30%. It was a different story for SThree though. The recruitment firm just managed to stay in profit as the recession sent revenue down to £280.6m from £295.4m. Pre-tax profit plunged to £2.7m from £21.8m, partly due to an £8.5m restructuring charge.FTSE 250 - RisersTaylor Wimpey (TW.) 37.00p +6.47%Domino's Pizza UK & IRL (DOM) 232.25p +5.81%Barratt Developments (BDEV) 174.25p +5.77%DS Smith (SMDS) 70.00p +5.66%Bovis Homes Group (BVS) 439.25p +5.34%Wellstream Holdings (WSM) 523.00p +5.07%Bellway (BWY) 707.50p +4.97%Marston's (MARS) 89.00p +4.71%Premier Oil (PMO) 1,173.00p +4.64%BTG (BGC) 176.75p +4.59%FTSE 250 - FallersFisher (James) & Sons (FSJ) 406.50p -3.67%Punch Taverns (PUB) 82.00p -3.53%Dechra Pharmaceuticals (DPH) 430.50p -2.99%SThree (STHR) 181.50p -2.68%Emerald Energy (EEN) 628.00p -2.56%PayPoint (PAY) 514.50p -2.37%Euromoney Institutional Investor (ERM) 221.00p -2.21%BlueBay Asset Management (BBAY) 238.00p -2.06%Computacenter (CCC) 215.50p -2.05%Moneysupermarket.com (MONY) 54.00p -1.82%