My down sleeping bag and down jacket have a conditioner built in to help the down repel moisture. Does anyone know if I can treat the outer shell with a rain guard like Camp Dry? I don't know if the spray just sits on the outside or actually permeates the down. I don't want to compromise the insulating values but would like to help protect them from condensation (sleeping bag ) and light mist, rain and the condensation of a rain coat (jacket).

I don't know about a wash in product but I'd assume a spray on type of water proofer would be fine. You would really have to over spray to completely soak and compromise the loft of the down.

I am by no means an expert. So if someone has evidence the other way I'd listen.

T

Nikwax makes a down wash that adds water repellency to both the down and shell. Keeps up with the loft too.

Items advertising use of fully waterproof down are filled with a material that has been treated via a nanomolecular or hydrophobic coating that allows each tuft of down to resist moisture. I wouldn't worry about a spray-on treatment of the shell material having any effect. I might avoid a full wash treatment, however.

Had never thought of this option, Merlyn. If you give it a try, please post your observations and the results.