Bought two units for our entrance bedrooms as we've been on a noisy major street. Set up them yesterday and the main difference in noise is wonderful. I went with the 6.4mm laminated glass and positioned the units around the entrance with the window sill to offer greatest hole. In https://holdenzefff.losblogos.com/26542512/the-2-minute-rule-for-london-sw3-secondary-glazing-services