Lumber prices have tumbled over the past 10 weeks as consumers retreat from do-it-yourself projects and builders slow the pace of housing starts. Despite the 46-per-cent drop in prices since mid-March, relief won’t likely trickle down to consumers for at least four weeks, and recent prices are still twice as high as two years ago. Cash prices – what sawmills charge wholesalers – are at US$750 for 1,000 board feet of two-by-fours made from Western spruce, pine and fir (SPF), according to Random Lengths, an Oregon-based company that monitors wood markets. The survey by Random Lengths shows prices fell US$150 last week to their lowest level in six months. …It will likely take four to six weeks before lower wholesale prices start being reflected at retail stores. Many outlets first need to sell inventory bought at higher prices, and those prices vary regionally. [Access to this story requires a subscription to the Globe and Mail]