I had a question last week about which underlay is best if you are looking for a sustainable option.
There are a range of underlays available however the ones that I think are the most available and also suitable for a home are:
1. Recycled cotton / felt underlay for deep cushioned areas like living rooms, bedrooms etc. This is the basic non rubberised version that should be available from all carpets outlets.
2. Recycled tyres underlay for heavy wearing applications like hallways, stairwells etc. This has been widely available through many of the main merchants.
Personally I would avoid all rubberised underlays as they will slowly decompose and also give off a range of toxic fumes as they do so. The amount of carpets I have lifted to find dust underneath – terrible stuff.
A word of caution though. You may specify and buy good underlay and some lovely natural carpets, BUT carpet fitters will insist on using glue! This stinks and is just not necessary as long as they fit the edge grippers well enough (and this is not difficult). Please INSIST on no glue. It might make their guarantee a bit more secure, but it also hampers any time that you want to lift the carpet in the future as well as stinking the house out for days.