Joining Tarpaulins for a Geodesic Dome

[alexben99]

Hello All,
I have a project this summer - a geodesic dome. The frame isn't a problem - PVC piping and DIY connectors seems to suit my needs, however, the waterproofing is a rather larger problem.
The dome has a diameter of 7 meters, so rather large, and the covering will be suspended inside the frame, so I need a very large, perfectly shaped and waterproof cover for it.
I intend to cut out the basic net for the covering in 6 parts, so I need some method of joining these sections of 200 gsm / 6oz tarpaulin into one dome. The joins I need to make are 2 meters long, and obviously have to be strong enough to withstand some considerable tension from the suspension.

My question is this: Does anyone know an inexpensive method of joining these tarps together which will also be strong and waterproof?

It's a tall order I know, but thanks in advance for your help.

 

[Norcon]

Mebbe they could be stapeled and then hot pitch poured over the joint.

 

[Dave54]

I'd have thought either some sort of adhesive, or sewing a double lapped joint (probably with some sort of strengthening tape) with a sewing machine.
What do the manufacturer's or suppliers suggest?
Also you could ask a sailmaker what to do?

 

[crank39]

How about speaking with some advertising banner makers/sign writers, often see large banners with joins in them