Info on Stucco and Plastering-June, 2018-Fifty-third
Driwall Rainscreen by Keene Corporation.
With big, mobile friendly pictures.
The only time I have seen rainscreen used in the washington, dc area, it was put on backwards.
Please don't put this on backwards, it does more harm than good. There is no excuse to put this on backwards or upside down. Instructions are included on every roll.
The back side, or drainage mat is made of plastic fibers.
The drainage mat requires the rainscreen to be put over another water resistent barrier.
According to zipwall, a water resistent barrier isn't required, the zipwall counts as a water resistent barrier.
From now on, we'll probably put on a layer of tar paper first. It can't hurt.
A flap on the bottom of the roll allows the water resistent membrane to be overlapped, and the drainage mat to be continuous.
water resistent barrier is also abbreviated "wrb".
A gap is left at the bottom for the drainage mat to work.
Water will probably never penetrate the wrb on the rainscreen, but why not do it right ? The rain screen
can prevent excessive cracking or rot if a metal flashing or drip edge fails, for example.
A plastic spacer is used to set a gap between the bottom of our weep stop,
and the top of the flashing on the drip moulding.
The rain screen, of course, overlaps the stop. You can put the rainscreen over the flashing first, then the stop.
We make the weep stop, or weep ground, by drilling 3/4" plaster stop. They make this out of plastic now, and metal
weep grounds are discontinued. Plastic weep grounds and plastic trim are probably quite useful in Florida
or warm climates where corrision is a concern, and a problem. I have seen a lot of failure
of plastic trim in cold climates, so we make the grounds ourselves.
One main advantage I like about the rain screen is the reason for two layers of tar paper. Building movement
is cushioned by the plastic fibers reducing cracks.