A.Tish Iorio, a member of
the National Guild of Professional Paperhangers and
owner of Creative Endeavors in Annapolis, Md.,
responds: Drywall has a paper face, so
wallcovering pastes adhere to it just as well as
they do to wallpaper. Unless drywall has been
properly primed, wallpaper paste doesn't have the
ability to release from it when it is rewetted,
resulting in the damage you describe.
Designed to be nonrewettable, wallcovering
primers contain acrylic polymers that provide a
barrier between the paste and the paper face while
at the same time promoting adhesion of the
wallcovering to the wall. They are more expensive
than regular paint primers, which are designed
mainly to provide a uniform wall color (usually
white) that won't influence the color of the top
coats. All of the major paint companies offer
wallcovering primers, but I use Wallpaper Prep-Coat
(Swing Paints, 323/816-3041, www.swingpaints.com).
I like it because it's slightly green and turns
gray when it comes into contact with drywall
compound that hasn't been painted, making it easy
to see where I need to apply a second coat. It also
has diatomaceous earth in it, which leaves a
"tooth" on the wall that aids adhesion.
A wallcovering primer should always be used
before applying any type of wallcovering. It can go
over bare drywall, primer, or existing painted
By the way, sizing (a diluted paste) is not a
good substitute for a wallcovering primer.
Consolidating products such as Gardz (Zinsser
Co., 732/469-8100, www.zinsser.com) have been
developed to help repair damaged drywall. Because
they bind both paper and paint layers together into
an impermeable surface, I use one of them whenever
a damaged wall surface has been skimmed with
compound or when a paint finish seems unstable. But
because they are very hard, they don't give paste
anything to grip, so I always use a wallcovering
primer over them before I hang.