Hi, I'd be very grateful for any advice on a project I'm contemplating... I've got a detached single garage built in the late 1920's with solid 9 inch walls and a pitched slated roof. On the opposite wall to the main vehicular entrance there is a personal door opening, the load above being supported by two timber lintels. I want to widen this opening to allow a car to pass directly through the garage. My question is what would be the best way of spanning the opening? I guess that taking into account end bearings, I'd be looking at a 2700mm lintel. Would two concrete lintels do the job, or is it necessary to use a steel lintel if available - the steel lintels I've looked at have all been for a cavity wall at that length. Thanks in advance for your help.