Heather85uk

Apologies to add to the theme of questions about deflection of rsjs over sliding doors.. slight panic.. as we are in construction.. (a two storey rear extension and loft conversion with gable window. ) we have a goal post design from our SE ( who we have not had a good experience with, another story) she has calculated to use a horizontal UB of 254 x 254 x 89kg we also want to spot weld a steel plate all the way across. however, express bifold have stated they require a deflection of no greater than 3mm And she has said that the deflection is 25mm and that it’s impossible to reduce this. the length of the UB is 6.7m span over sliding doors 6m. They are bottom hung. After hours of reading I am gathering that increasing the height of the beam may help? 356 or 406 using a shallow UC..( taller and lighter ?) Will pre-cambering help? any ideas on cost increase? is it possible to add a layer around the frame using a compress-able material that will absorb some movement ? As well as specialist silicone. Live load and dead load shown on calcs below.. Any suggestions on how to not have dis functioning sliding doors and cracked brickwork? Losing sleep over this one ! Any help gratefully received! Thanks in advance, Heather