Sorry I didn't respond earlier, but I've been out of town.

Recently the Carolina Area Registrars (CAR) met in Greensboro at the
Weatherspoon Art Gallery.  Nora Kuper hosted the meeting and presented a
program on their experiences with the installation of UV protection on
windows in their lobbies.  Mark Shumate, a consultant with Clear Defense
Film Technology, also made a presentation.  He noted that no film is 100%
effective.  Even if a window faces north, UV rays bounce off other objects
and can harm works of art (& artifacts).  The life expectancy is 25-30
years, then you can add another layer.  There is no damage to historic
glass.

However, I was bothered about applying this film to original glass in
historic buildings.  I have since found out that a historic house here in
Raleigh decided to install UV shades.  The bottom of the shade is held
down by a metal bar painted to match the color of the window sill.  The
effect is hardly noticeable.

for further information, contact Nora Kuper @ (910) 334-5770; Mark Shumate
@ (910) 275-0970; or Sarah LeCount, Mordecai Historic Park, Raleigh, (919)
834-7314.

Good luck!

Martha Battle Jackson, Registrar        (919) 733-7862
NC Historic Sites                       Fax: (919) 733-9515
109 East Jones Street                   [log in to unmask]
Raleigh, NC  27601-2807
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