I had something rather large delivered in monster bubble wrap with 40mm diameter bubbles, so I decided to try "bubble glazing" some windows at home. I am impressed with the results!
The coldest room in the house is the bathroom, which is approximately 3m x 3m and has a double hung sash window facing north. The window is about 0.75 square meters, which is too small to get the full benefit of passive heating on sunny days in winter, unfortunately.
The ceiling is insulated with sarking, R3.5 fibreglass batts and AirCell reflective blanket, which is R2.2 conductive and R5.5 reflective, but this doesn't cover where the rafters meet the joists. There is one external wall which is double brick and the internal walls are single brick.
I covered the glass panes with cut pieces of bubble wrap. Not only is it effective (the bathroom now doesn't feel colder than other rooms) but it doesn't look too bad either!
I also have a room with no external walls or windows, just a 600 square skylight. The skylight has an opaque cover on the roof about the same size and the gap between the cover and diffuser is boxed in with galvanised sheet. The ceiling is insulated with R3.5 fibreglass and a reflective blanket.
I cut a piece of bubble wrap to sit on top of the diffuser and was surprised the following morning that this room had retained more warmth overnight than other rooms.
These are hardly scientific results, but the differences were quite obvious. I encourage others to experiment either as a temporary solution or as a proof of concept before committing to “proper” double or secondary glazing.
