dunno what polycarb is but we had a lidls coldframe, made of plastic.
The base had no bottom and was double thickness brown, hollow plastic type effort.....the lid wasn't clear but opaque, stripey whiteish plastic.
It cost about twenty quid...
It was crap
broke straight away.....got blown around the garden cos had no anchor points. Then next door's cat sat on it and broke the lid....and it wasn't a very big cat either
If your ground isn't completely level there are big gaps underneath....I swear slugs sheltered from the rain there
