Working from equipment and materials available in medieval Europe
(circa 1150), how many hours would it take someone to make a
high-class dress?
Assume the dressmaker is proficient, that the design has been
previously settled, and that the material has just become available.
If the material matters, assume wool.

Buy cloth in French festivals or card the wool and weave the fabric?
Fancy wedding dress or simple workaday outfit?

She specified a "high class dress"  and said we could assume wool if
we wanted. I would guess it would take a couple days, depending on
details. Maybe a bit less.

I think we can assume that the dress would be a "Bliaut", described in
detail on this site:
http://www.chateau-michel.org/belle_bliaut.htm

I didn't read the text, so I don't know if a bliaut relates to these
simple patterns:
http://bliautlady.50megs.com/bodyover.htm

If you search Google Images for bliaut, you will find five pages of
pictures, some linked to patterns and descriptions.  Obviously, if the
skirt includes gores to make it fuller, there will be much more sewing
necessary.  Someone would have to know how cut edges of the cloth are
treated, but with wool, perhaps they needn't have been secured against
raveling.  Any decoration would be an additional time factor,
especially if it had to be made in the time frame  - instead of sewing
already available "whatever".

Stitching the thing together would not take that long
- but I would imagine that there would be a fair bit of embroidery

A 'high class' dress is a demonstration of 'conspicuous consumption'
- so the classier it is, the more work has gone into it

How interesting - your post appeared before mine

What got me thinking was Hogarth's (whoops 'Artist unknown') portrait of Henry VIII
- bling in embroidery

On the other hand, I picked up from Dorothy Dunnet, that at one time
black was by far the most expensive dye
- it might be a 'little black dress'

It seems to me that the type of needle and thread available might have
a bearing on the speed and efficiency of sewing. I've read that
needles were made of metal, bone or thorn. The metal ones were
considered very valuable. I also wonder about other sewing tools,
i.e., scissors, thimbles, thread spools, etc.

Great minds and all that, Frde.
I know a bit about natural dyes.  Black is corrosive, walnut husks and
other sources of tannins.  Black sheep's wool is rather a very dark
brown and fades lighter  - even on some sheep.  They would have stuck
to basic red, blue, yellow and combinations of two colors.
I agree with you entirely about embroidery, probably the decoration
for a "high class dress", and time consuming.

Maybe you were thinking of one of Holbein's portraits of H VIII?

I darted off to look at the cover of Antonia Frazer's tome on the
wives of Henry VIII - then checked inside the dust cover.
My guess is that it is 'school of Holbein'

I've a suspicion that things were not that different in 1150
- Constantinople was still going strong then

Really classy stuff would have been influenced by the then centre of
culture, but adapted for the climate.

One of the things that has bemused me over the last 10 years, is that
there is a lot more history than I was taught.

And the worst part of it is that we were around and remember some of it.  ;)

I'm the original question poser (and not, incidentally, a "she", but
that's fine :).  The dress in mind would be for a celebration -- along
the lines of a New Year's Eve society gathering (not that there were a
lot of those in 1150).  Formal but less so than a wedding.

I probably wasn't clear but this is for a work of fiction, not for
actual construction by me.  (I'm lucky I can lace shoes, much less cut
and make a dress.)

Everything so far has been tremendously useful -- thanks to everyone who posted.

Right, only one New Year's eve celebration in 1150   ;)

So your time contraint is the late arrival of the material  -  missed
the last ship across the Channel before Xmas?

Of course, I wasn't there, but my understanding of medieval life is
that a new party dress would have been rare except for the wedding or
a really big event where the lady was a main player.  A bride's
trousseau was meant to outfit her for life, including material to be
made up later.  Everyone would wear the best they had for a
celebration, recognizing that others were doing the same, much as was
the case into the early 20th century in the parts of Europe where
local custumes were worn.

That is, of course, not an answer to your question, just a personal
impression that the situation is rather hypothetical.  If you insist
that a new dress must be made in a short time, I would estimate a week
 - with some sloppy embroidery.  Or maybe a clever somebody comes up
with the idea of appliqueing existing embroidery on the new dress 
(but her girlfriends would notice, as they would notice the hastily
made embroidery). Don't know if your storyline has to worry about
that.

Good luck!

This won't help you with the "how long would it take" question, but
here are a few tidbits that might be of interest anyway, from an
interview I did a few years ago with Dublin costume designer Consolata
Boyle, who did the amazing costumes for the Glenn Close (Eleanor of
Aquitaine) and Patrick Stewart (Henry II) "Lion in Winter" re-make. 
The "Lion in Winter" is set in 1183, so it's around your time frame.

Even though the characters in your work aren't royalty, here's what
Consalata had to say about dressing all class levels for that time
period:

"It's not easy to research the clothes, as there's very little--
obviously -- in existence.  The research is usually monastic resources
and church windows.  And the most amazing tapestries, wonderful
tapestries, where they have beautiful visual references.  So that was
really great.  It's a more complex time to research than maybe others
-- but it's more interesting.  It's a joy, really."

"It was known that the peasantry would have had wools and linens and
the aristocracy and the nobility would have had silks and linens.  A
lot from the east, a lot of silks from the East, from Byzantium. 
Beacuase they traveled so much.  They were traveling to the East and
bringing all this back."

"And very subtle fabrics.  The nobility were very, very sophisticated
on that level.  And very beautiful.  The clothing was very, very
beautiful."

Not sure if any of this is helpful to you, but perhaps your character
wouldn't be wearing wool, if as you say, she wants a "high class
dress."  Wouldn't she aspire to something more special for this
occasion?  Especially if she's living near the royal court.

gilroy0-ga,

I haven?t been able to find anything on estimating how long it would
take to sew a 12th century high class dress but the search has been
fun. The resources below will provide some hints that you might be
able to use.

~ czh ~

http://www21.brinkster.com/annascrafts/textile.htm
http://www21.brinkster.com/annascrafts/sew.htm
·  Costume beginning before 1500

http://www.chateau-michel.org/belle_bliaut.htm
The Beautiful Bliaut:
Haute Couture of the Twelfth Century

http://home.flash.net/~wymarc/asoot/magi/magi.htm
Costume for a 12th Century Lady

http://www.virtue.to/articles/extant.html
Extant Clothing of the Middle Ages -- Photos of the real thing.

http://www.faucet.net/costume/research/12thcpaper.html
http://www.faucet.net/costume/period/medieval.html
Eleventh and Twelfth Century Gowns--Influences and Discoveries

http://www.fetteredcockpewters.com/page_sewing.htm
Medieval Sewing Kit 

http://www.currentmiddleages.org/tents/costuming.htm

http://cunnan.sca.org.au/wiki/Category:12th_Century