Well it seems now that Perko door closers are not fire rated any more ,the only Perko product which is fire rated is for a 54mm door thickness , I have a 45mm door thickness, and we have been asked to change to the New British fire rated over head door closer which is fine , what happens with the existing Perko in the door surely we need to remove the Perko ,then what happens to the existing hole in the door and how do we make that good to keep the 30 mins fire rate door , I would grateful for any input on this matter . Yours Michael Douglas
