I have the Katabatic Bristlecone bivy which I really like. I haven't been using a groundsheet under it but after reading some posts on here I'm starting to wonder if I should. What do you do? If you do use one, where did you get it?

I use 1443r Tyvek, lighter than the standard house wrap and tougher than polycryo. http://www.intothewind.com/shop/Repair_and_Kitemaking/Fabric_for_kitemaking_or_kite_repair/Tyvek

Edited by CLebow on 04/16/2012 17:30:26 MDT.

I use my sleeping pad, thermarest z lite, as ground sheet.

no groundsheet for me.

Protect your investment of the Bristlecone. The groundsheet is multi-use item at a minimal weight gain. They keep your bivy clean and if you have a sleeping pad it will help you with "No Punctures" Preen the area first! At break time you can throw it down to rest for a while.

No ground sheet - that's what the bottom of the bivy is for. Why carry extra weight?

I did't use extra tarps / floors under my regular tents either! Never had any problems with old tents, new tents, or bivies!

I use a GG Thinlite pad, full length, under my bivy. 55g and extra comfort, and protects the underside of the bivy.

+1 : GG thin pad, protects my neoair from punctures too, good to stretch out on on a mid day stop . Also, if not using a bivy, polycro over that to keep water out and kit out of the dirt.

Edited by jhansford on 04/17/2012 02:15:10 MDT.