Let a woven square of 10 x 10 cm = 100 cm2.

Concerning the weft, a passée uses 40% more
thread than the requested warp width.

Calculation : 10 cm + 40% = 14 cm of weft (for a
width-a passée).
If the weft is made up of 6 strands of wool,
and we need 14 cm of wool (weft) to cover 10 cm of warp : 14 cm
x 6 strands = 84 cm.
For the height of our square, the number of duite
will vary depending on the size of the warp and the weaver’s way of weaving.
We will therefore take a warp of 13 portées
(average size used for the first exercises). We will estimate an average 60 duites
(that is, 120 passes - passées) necessary to complete the weaving
on a height of 10 cm.
There will need 10 080 cm of wool :
120 (passes) x 84 cm (14 cm x 6 strands) = 10 080
cm (that is, 100,80 m) of wool length per 100 cm2.
How much wool will be needed for 1 m2 of
weaving in 13 portées ?