Tyvek

Carolyn Lamb <carolynpaintingconservator [at] rocketmail__com> writes

>I have to make a waterproof dust cover for a church painting 26 feet
>high by 21 feet wide. I was thinking of using tyvek but will have to
>join several 3 metre widths together.

I have used Tyvek as temporary enclosure for historic buildings. It
allows passage of water vapor while resisting (not necessarily
completely preventing) the passage of liquid water. If the protected
object were to be subject to much direct water, there may be some
dampness on the interior of the Tyvek depending on relative humidity
levels. I would experiment before deciding on its use. It does block
passage of free air flow, so you may want to ensure that there is
some provision for venting at bottom if the painting is going be
covered for a significant length of time. Consider using a fabric
filter material similar to what is used in vacuum bags.

For joining seams, I would experiment first using the manufacturer's
tape, which is specifically designed for construction applications
and bonds very well. DuPont Tyvek Tape is constructed of an oriented
polypropylene film coated with an acrylic adhesive. I would use the
tape on both sides. The web site for information is

    <URL:http://www2.dupont.com/
      Tyvek_Construction/en_US/products/commercial/products/tape.html>

    **** Moderator's comments: The above URL has been wrapped for
    email. There should be no newline.

If you were to sew the seams, you would still need to use a tape to
ensure waterproof qualities. I am not familiar with the use of any
heat sealing adhesive, but it probably would work well. You could
possibly even lap and heat seal the product itself since it will
melt at high temperatures. Heat welding may alter the products
properties, however.

John Horton, Architect
117 Hazel Street
Hendersonville, NC 28739
828-243-7411


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                  Conservation DistList Instance 20:41
                 Distributed: Sunday, February 25, 2007
                       Message Id: cdl-20-41-003
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