Dumb silnylon question

I noticed a "shiny side" on my Seattle Fabrics 1sts sil that I bought and used on a previous project, but I've got 2nds on the way from Noah Lamport for a tarp. I imagine there's a difference between sil-impregnated vs sil-coated…

I haven't used sil extensively but it's only a matter of time before the smarter BPL faithful chime in.

Any problem doing this?

Nope. Both sides of fabric are the same. That has been my experience at least with all the sil I have bought over the years.

The weight discrepancy you see is because they give the weight of the fabric before coating.

Yeah, go ahead and flip your patterns for the best fabric savings. If it's silnylon, it's coated both sides (also referred to as "impregnated" – manufacturers call it double-coated). So, all that to say, it's the same on either side. And if it's a 30d (1.1oz w/o coating) silnylon, then the extra weight should just be coating.

– Scott

Thanks for the confirmation, folks.

Scott, I bought the silnylon from your site–excellent, fast service by the way, and the product looks great (and a nice price). WRT the weight–I expected 1.4 oz-1.5 oz w/coating and this is more like 1.6. No problem *at all* with that–the weight gain is trivial. I was wondering if this meant there was a bit more sil, and thus the fabric was a bit more waterproof. Seems I've read that some silnylon 2nds are less waterproof than some 1sts.

Obviously, buying 2nds I wasn't expecting perfection. But in my limited experience, this looks pretty close to it. Can't wait to get started on my shelter.

Thanks again for the help.

I noticed the same thing with one batch of silnylon I bought a while back. It weighed in at 1.6, where most of the sil I have used recently weighs 1.3-1.4