What type of shade cloth is best for my situation

[Fairorchids]

Glass lets almost all light through, while plastic & twin wall polycarb absorb about 15%.

Also, shade cloth is usually rated with a number, which indicates how much of the full sunlight it blocks.

In this part of the US (NJ/NY/CT), I would normally provide:

0-20% shade for Cymbidiums, Laelia anceps, Australian Dendrobiums, reed stem Epidendrums & Vandas.

30-40% shade for Cattleyas, Oncidiums, Ascocentrum, Aerides, Rhynchostylis, Denbium phalaenopsis & Latouria Dendrobiums.

60% shade for Angraecums, Paphs, Phals & Sarcochilus.

So, if you have greenhouse cover that absorbs 15%, add 30% shade cloth = about 60% getting through.

Then add an internal layer of 30% shade cloth over the low light plants = about 40% getting through.