Hi it's my first post :)
I just got lost at choosing the right materials for my new tent.
Let me start of that long time ago I have bought a crappy tent for just a few dollars but it was really not useful not only because it was leaking very much but it was not comfortable to take the time on rainy weather just sitting in it (because of the small height). I have fixed the leaking thing thou in a very simple way: I have took a PVA glue and stirred it in some amount of watter. Then took a sponge and washed all surface of the polyester tent. Now it has good waterproofness but bad breathability even it is not a big deal to me as the tent has lot of ventilation holes. Surface got some stiffness after that but it is still ok.
Why i am telling you that is i would like to make myself a tent that is more comfortable and is lightweight too. I cannot afford to buy a good one from the store so I look at what I can make myself. I have a few choice of materials but not sure what should I use best. I live in Lithuania and i think we have no silnylon material at the stores, but I have seen much choices of 100% polyester that is used to make a cloth lining. It cost around 1$ for a one meter of a 1.5 meter wide piece. The main problem it has no water resistant coating. We do have few types of Tyvek: http://www.senukai.lt/index.php?cl=detail_search&alist_tab=articles&sKeyWord=tyvek&sCategoryID=—&x=0&y=0
As you see the one tyvek (the one with green color) is not suitable as I think of it's wooly surface which will collect all debris, but the other two is ok I think.
Do you think if I make ground part of tyvtyvek and roof part of polyester coated with PVA glue will be a good choice?
I was searching where can I get cheap silnylon on other countries that could send me it by mail, but found it to be a overpriced to me and then the materials would cost me the same as I would by a good new tent from a store..
Sorry for the messy post and probably a bad English, hope you understood what I am asking and I would really appreciate your effort to answer :)

