Bought 2 units for our entrance bedrooms as we are on a loud most important road. Installed them yesterday and the difference in noise is astounding. I went with the 6.4mm laminated glass and positioned the units to the entrance on the window sill to provide greatest gap. Putting https://precisionslanttweezers10864.boyblogguide.com/33626906/5-simple-techniques-for-acoustic-secondary-glazing