I've fitted a steelbeam which is a 6mm steel box section 150wide x 250 high with a 10mm plate 250mm wide welded to the bottom over my bi fold doors at a rear lean to extension.The beam is 5m long and i've sat it on a padstone at each end ,the beam is parallel with the wall so the box section sits on the padstone and the front of the 10mm plate sits on the brickwork outside.I've sat the beam on the padstones with a bearing of 150mm is that enough?