Buoyancy from bottles...but do they degrade?

I'll be interested to see what condition the c1997 milk containers sealed fore and after in my tender are like when I replace all the woodwork later this year!
 
Clearly there are some innovative and analytical minds at work in this thread so.....
Do these pet bottles have any noise or heat insulation properties when boxed into an enclosed space?
I'm trying to reduce the ambient temperature around my fridge to cut down on current draw and ice making time.
 
I still have a long list of vital matters to attend to, even before I can relaunch this year. Upturning a 17' boat in very limited space to fix the new keel-band requires all sorts of preparation, and patience from impatient SWMBO.

And I haven't got a drysuit yet. No great hurry, considering the weather and sea temperature.

I've no idea about thermal/sound insulation from plastic bottles. Rather meagre I expect - they're just empty, thin-walled plastic bottles - not much to baffle the movement of heat or noise.
 
Top