I am going to install a watertable with stucco above and siding below (probably Hardiplank) but I’m unfamiliar with watertable installation. I can’t even seem to get any information online. My first question is how is it typically installed? Is it one piece or two?
Also, the stucco guys have installed building paper on the upper portion which overlaps the weepscreed and applied the scratch coat. They have not installed anything under the weepscreed and building paper to come down behind the watertable. They are assuming the watertable will be installed below the weepscreed and the lower course of building paper shall start from there. Surely water will get between the weepscreed and the watertable and down behind the watertable /building paper etc. I guess I can slide sheet metal up behind the weepscreed/building paper but I would have prefered a band of bituthane behind the watertable. Any thoughts?
Thanks
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.....but I would have prefered a band of bituthane behind the watertable. Any thoughts?
If the water table that you are talking about is the trim piece that is below a run of some type of siding (like stucco), then you don't want the bituthene to go behind the water table.
You want the moisture barrier -- in this case the housewrap that is behind the weepscreed -- to END ON THE WATER TABLE. That way it catches all of the water to the and directs it to the outside. (There will be water, no matter how much you think there will be none.)
By the way. you do have housewrap behind the weepscreed don't you?
Unless you're the lead dog, the view just never changes.
The bituthane I'm referring to would be in addition to the housewrap which itself would sit on the weepscreed and terminate at the watertable. If driving rain, for example, forced water below the weepscreed and above the watertable at the onnection to the wall then surely it may get behind the watertable and then down behind the lower membrane. The addition of bituthane would prevent this from happening by directing it over the top of the lower membrane?
The bituthane I'm referring to would be in addition to the housewrap which itself would sit on the weepscreed ........
Perhaps my understanding is based on a misunderstanding of your terminology. The stuff that I call weepscreed is a flexible fabric, rather thick (1/4"?), with lots of airspace, that is applied to the entire wall. If that is the case, then read on...
The housewrap should be applied directly to the sheathing. Then the weepscreed goes over that. Then the lath, then the stucco. At least that's how I understand it.
It's done that way because stucco, like many siding products, is not waterproof. Water will weep through it. In addition, water vapor will get behind the stucco in the form of air. Then it will condense there. The weepscreed is required so that all of that water will have a path downward.
And the housewrap behind the weepscreed prevents that water from rotting out your house. If your stucco contractor installed the weepscreed directly over the sheathing, then put the housewrap on top of it, you probably have a big problem.
The water table is what catches all of that water, and gives it a path to daylight. By the way, DON"T CAULK between the water table and the stucco. If you do, that path to daylight is blocked.
Also, if the housewrap is properly laid on the water table, there is no need to worry about wind-driven rain. Any wind driven rain will be directed back out to daylight by the same path as the condensed stuff. But only if that housewrap is on the sheathing.
Unless you're the lead dog, the view just never changes.
Stucco weepscreed isn't a fabric....it's a flashing , has a vee turned sideways that's as thick as the stucco, & has holes punched in both legs for water to drain through...the point of the vee acts like a plaster ground....
The tar paper or bituthane behind the stucco should lap over the flat upper part of the weepscreed (but not onto the vee)....a second layer of housewrap, tarpaper, or bituthane should tuck under the weepscreed & continue on down behind the watertable and siding...
any water that comes out the bottom holes in the weep screed should drip onto the watertable, & run off it...the watertable needs to be bedded in tight to the sheathing...
that's if you aren't building a rainscreen wall, but even there the principle is the same....
Tim
I don't know if this is what you had in mind, but check out HGTV Pro Videos on preventing water migration into a home. The specific video can be found here:
http://www.hgtvpro.com/hpro/pac_ctnt_ihdr/text/0,,HPRO_20976_28891,00.html?cat=0&vid=755
Hope it helps.
Griff