We’ve had our first setback today. The pane of glass which we were going to use (the one that was recycled when we had the catflap fitted) shattered while it was being moved. Not a huge disaster – it was an opportunistic plan anyway – but it does mean we’ll need more glass!
Artis is now working on fitting the other frames. The problem with double-glazing (or in this case, quadruple-glazing) is that once the unit’s sealed you can never open it up again. This means that the glass has to be clean to NASA-like standards before the next pane is fitted. So he’s shining halogen lamps at each pane from both sides so he can see to clean any speck of dust or grease.
Today the lobby floor went in. The lobby is primarily a utility area, so we’re not going for hessian walls etc – just plasterboard walls and a chipboard/carpet-tiled floor (plus a doormat so we can leave muddy boots in the lobby when coming in from outside). The principle of floating rooms has been maintained throughout – neither room actually touches the lobby flooring, so no vibration can be transmitted between the floorboards.
I took my first measurement this afternoon of the amount of SPL (Sound Pressure Level) reduction the building provides. There are still a few panes of glass to go in, so actual performance will be better than this. On the main road outside, the reading is around 88dB. Inside the studio it averages around 40dB – though some of that might have been my own breathing – it really is quiet in there. I’m using the rather limited iPhone Decibel Meter and will be testing the levels with pro equipment soon, but it’s already clear that I’m going to be able to record whispery vocals or delicate unaccompanied acoustic guitar without any discernible traffic noise on the recording.