got mine made by doyle in southampton. any sailmaker will quote you, using a plastic-coated mesh with edges bound with pvc fabric. mesh is around 3mm holes with 2mm wide strands. problem with this type is that it takes a while for solid water to drain through, mine ripped out of its bolt rope in 24 hours of head seas.
next time i will get one made of stitched webbing or even fishing net as i saw on one low-budget cat in bermuda. sight cheaper and virtually nothing for wind and water to get hold of.
Tried the fishing net idea and it really was crap. Far 2 much give, but then I am a little over weight, and very unsteady in any sort of sea. Have now altered the front deck nad have put hardwood slats on top it some new steel poles. Also altered the stern and with a bit more steel made an after deck as well. Both seem to work quite well and have not experienced any probs with water yet. I have a very low bridge deck clearance and being a 20 year old design am relatively narrow beam.
Mike
sounds like a pretty hefty solution. depends on your weight-carrying ability. if you're heavy displacement eg. prout, the extra weight won't be too much of a problem. in my case i'm trying to keep to 5.5 tonnes on 12m loa, 7m beam, not easy!
It really did not add too much as "lightship" weight was about 4 tons and all up cruising came to about 5 - 5.5. She is 9.21m x 4.09m and 25 years old. Oh I nearly forgot she's made of steel!
Mike