should envelope be stretchy or stable?

I have read that dimensional stability is desirable in balloons and blimps. But if an envelope were stretchy, it would make construction easier, and it could enable the elimination of baloonetts.

This is because a stretchy envelope would require fewer gores, and a stretchy envelope will enlarge as volume increases so that baloonetts would be unnecessary to reduce pressure.

Stretchy but firm? Hmmm... sounds like shrink wrap film.

I've discovered the solution to expensive envelopes!

 GIANT SHRINK WRAP! You can get it in 12' X 250' rolls,  weighs only 70 pounds, for only $200 for 3,000 square feet!     http://www.associatedbag.com/product.asp?cn=ABC&c1=FLM&p1=FLM_S400&c2=GG01&pid=21-7-02&Type=

So, we don't have to cut and sew expensive rip stop sail cloth and worry how the wrinkles look. We don't have to worry about rips and tears from landing in treetops. We can recycle the darn envelope whenever we want to, it's so cheap.

Who says we can't make a SkyBoat for $10 grand? Who said that? We just got closer ~~ with shrink wrap.  It's easy. You just wrap your lightweight aluminum/fiberglass frame with shrink wrap then get out your trusty heat gun and this stuff tightens right down on the frame and holds it tight firm and stable. Some seams may need ductape for solid closure.

Plan to fly.

Just noticed the film widths are available in 16, 20, 24 and 32 feet! Quite a convenient range for any size gore you need. I think the media will go viral when we tell them we are making shrink-wrapped flying saucers that float with helium!   {8-0>

Make your Flight Plans now!

Shrink wrap is interesting. It would make for easy construction if you cover a frame with it. It might contain methane or hot air, but you would need an internal balloon for leaky gases. The internal balloon would not need to be accurately shaped if it is big enough; because, it will just fill the available volume. You could use many smaller balloons, but I don't really like that approach. 

I would prefer it with a lifting gas that it can contain economically.