These are examples of what I might have dredged up, using "specifier + préscripteur + Bourth" on Google, admittedly, because the ProZ search engine .... aspirates. I think it's a ploy to keep the site active; after all, if ProZ were to have – and retain – and provide direct access to - all the answers, people might stop paying their money. But never care, Big Brother is keeping watch ... and keeping a record ...

http://www.proz.com/kudoz/french_to_english/other/342618-cap...
http://www.proz.com/kudoz/french_to_english/business_commerc...
http://www.proz.com/kudoz/french_to_english/construction_civ...

And here are some of the many examples Wiley Wig Wrother has come up with :

Launched in February 2009, Barbour Product Search initially had a massive 24,000 pages of online content, now there's over 28,000 pages of fresh, detailed construction product information - for the architect, contractor and BUILDING SPECIFIER audience.
http://www.drillstar.net/media_centre_feb.htm

1. Specification Writing for Architects and Surveyors: Amazon.co.uk ...
By use of checklists, this book provides a practical tool for the BUILDING SPECIFIER. This new edition features changes to specification classifications ...
www.amazon.co.uk › ... › Civil Engineering › Surveying

HOUSING ASSOCIATION MAGAZINE brings the BUILDING SPECIFIER the latest news and developments relevant to the construction industry within the Social Housing ...
www.waverleycommunications.co.uk/readers/index.htm

determined by a licensed engineer or architect. Consult the BUILDING SPECIFIER for proper fastening recommendations. TOLERANCES (ALL PANELS). Panel Weight ...
images.listmax.com/download:1/7e08a0c2/Traslucent_Panel_Data_36.pdf

This either directly or indirectly affects everyone involved in building processes, including the owner, architect, BUILDING SPECIFIER, builder, surveyor, ...
www.archmedia.com.au/aa/aaissue.php?article=15&issueid...3

Therefore this information cannot be determined by the building manufacturer and must come from the BUILDING SPECIFIER or Architect/Engineer of record. ...
www.heritagebuildings.com/help4po/ibc_loads.htm

File Format: PDF/Adobe Acrobat - Quick View
options and glazing specifications are determined by the BUILDING SPECIFIER when determining the energy rating for the building. North Elevation. - Shaded ...
www.dowell.com.au/.../pdf/02457_DowellTechBro_14-16.pdf

As for the pilote part, is this a ginormously humungous project? If so, there might be trade specifiers – you know, from the guy who tells you what nuts and bolts to buy, what tap washers, what taps, what toilet seats, all the way up to the guy recommending the air conditioning system or neurosurgery positive-pressure and filtering system – and some senior guy managing their specifications, this guy being a sort of "general specifier" or "super(visory) specifier", not in the the sense of a general dogsbody or a guy in fancy satin tights, but more as in "superintendant" or "secretary-general", or "superintendant-general" (si, si, ça existe).