Anybody laid two lots of underlay?

Had a request today on a very tall pointed building in London to lay a specially made carpet with the borders already inlaid,
To be laid on two layers of underlay, two areas are lift lobbies around 5m long, but a larger area which will be around 15m long by 5m
Now would you use two layers of durafit, sticking both together or try to stretch it ?

 

I used to do the playbarn type things, you sometimes see attached to pubs.
We used to use 2 layers of Durafit. The top one at right angles to the bottom.
1st layer taki
2nd F3
Carpet F3
It actually felt o.k underfoot. Not spongy at all.

 

I've double stuck it with cloud 9 contract on a domestic job and it was fine! I would probably be ****ting myself about it on a contract job tho

 

2 dura fit should work but for what reason do they want it doubled?

 

thanks boys
its for a very high end contract job, hotel bedrooms , and restaurant, meeting rooms
its all in hand tufted carpet and some of the areas are 19m x 7m in hand tufted carpet with a beautiful patten its like a work of art, its not just one its about 10 areas

Anybody up for a challenge

 

Not really

 

Just getting up is challenge...lol

 

Can you not use durafit system 10 instead ? would love a go at that but live too far away I think