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In most applications, Sure Cavity™ (SC 5016, SC 5032) and ,10mm Sure Cavity™ (SCMM 2516, SCMM 2532) are sandwiched between a moisture resistant system on a structural backup wall (in this case CMU or concrete) and expanded metal lath that the scratch coat mortar is embedded into. Sure Cavity™ can be temporarily held in place with dabs of Sikaflex® 11 FC. Immediately install expanded metal lath and fasten as to lath manufacturer’s specifications to meet code requirements (see ASTM C1063–06 and the Northwest Wall and Ceiling Bureau's Field Technical Information).
For more information, visit HyperSpecs® Wall Details
If you have additional questions, call 1-800-879-3348.
In most applications, Sure Cavity™ (SC 5016, SC 5032) and 10mm Sure Cavity™ (SCMM 2516, SCMM 2532) are sandwiched between a moisture resistant system on a structural backup wall (in this case a nailable sheathing) and expanded metal lath that the scratch coat mortar is embedded into. Sure Cavity can be temporarily held in place using a common hammer stapler with staples long enough to hold into the sheathing. Remember, this is a temporary fastening only. Use as few fasteners as possible. Immediately install expanded metal lath and fasten as to lath manufacturer’s specifications and to meet code requirements (see ASTM C1063–06 and the Northwest Wall and Ceiling Bureau's Field Technical Information).
The exterior cladding or veneer will ultimately hold the Sure Cavity in place. The same fasteners used for the lath or cladding can be used to hold the Sure Cavity in place over the rigid insulation until the lath or cladding is installed. Only install as much Sure Cavity rainscreen as can be covered by lath or cladding each day.
No. End and course edge lapping of the corrugated plastic is not required. However, do lap the four-inch fabric skirt on top of the course beneath it to stop the mortar from clogging the channels.
Corners, both inside and outside, are recognized stress points. Good construction material application practices recommend that materials wrap around corners and extend onto wall surfaces to the nearest structural member in an alternating pattern every other course. (This statement does not apply to corners that are expansion joints or control joints.)
The key word here is “systems.” Details make up systems. Masonry Technology Inc. is the only manufacturer of rain screen drainage technology that designs, manufactures, and markets complete systems. Communication is another reason MTI’s moisture management systems are superior. MTI leads the industry in communication technologies with highly detailed wall drawings, installation animations, and online webinars.
Better technology with better detailing and better communication skills result in better moisture management systems.
The discipline of moisture management can be separated into two major categories: moisture resistance materials and drainage. MTI is in the drainage business. House wraps like Tyvek®, and in fact all moisture resistant systems, function better when installed in conjunction with a predictable drainage system.
The moisture damage risk factor does vary with the amount of moisture that may be present. That is true from geographic location to geographic location. It is also true from within the same building, from detail to detail.
The risk from moisture intrusion damage varies. What is also true is that the amount of moisture and the amount of damage varies. Sometimes, a very small amount of water does a great deal of damage.
In most cases, the cost of managing risk costs less than damage from the actualization of risk.
You would think the term “weep screed” meant a screed that can weep out water. Unfortunately, that is not true. Some of the major weep screed manufacturers actually say so in their literature. In literature for their weep screed, Alabama Metal Industries Corporation states “The holes in the 'V' stop act primarily as a keying mechanism and also offer minor moisture weeping capabilities. As stucco cures, it will shrink slightly away from the “V” stop allowing moisture to flow down the building paper and exit down the sloped surface.”
The draining capacity of three-coat stucco without a rain screen drainage plane is virtually non-existent, so it really doesn’t make much difference if a weep screed works or not. But when a high-quality drainage plane is installed, moisture will move from a high point in a wall, where it enters, to a low point quickly. If the weep screed provides inadequate drainage, it will be a real problem. The L & R Weep Screed really does weep. The L & R Weep Screed was designed to weep, and that is the difference.
There are people that believe weep tubes and sash core ropes efficiently drain or wick moisture out of cores and cavities of masonry walls. They are wrong. The only time these devices work is when you do not need them. Water does not drain out of the tubes or wick through the ropes. What actually happens when moisture does drain out of walls at these points is when the tube or rope forms the bottom side of the bed joint and voids are created at the 5:00 and 7:00 position. Why would moisture rise up to run out a tube? And as far as ropes wicking moisture out of cores or cavities or masonry walls, I have one recommendation: do not get in a wicking contest with masonry.
MTI weep systems work, because they form the bottom side of the bed joint of mortar creating 4 (¼” x ¼” holes) every 9 ½” at the lowest point of the core or cavity of the masonry wall. Weeps work when there are a lot of them and when they are all at the lowest point of the core of cavity. It’s a math thing (more works better).
Weeps do not work until the moisture gets to them, so do not forget the rain screen drainage plane portion of your moisture management system.
Call MTI at 1-800-879-3348 or email us at firstname.lastname@example.org and we will direct you to the nearest product source.
Yes! Call MTI at 1-800-879-3348 or email us at email@example.com and we will be happy to serve you.
Masonry Technology Inc. recommends 10mm Sure Cavity™ whenever existing wall details (window trim, mounting flanges, etc.) are compatible with the depth of the product. Coastal areas of Canada require 10mm by code. Most full stone and full brick veneers should use 10mm Sure Cavity™ (SCMM 2516, SCMM 2532).
Most thin veneers (stucco, thin brick, thin fully-adhered stone) and wood cladding systems will use 3/16” Sure Cavity™ (SC 5016, SC 5032).
Gravity Cavity™ (GC 1816, GC 1832) is MTI's economy drainage plane. It is similar to 3/16” Sure Cavity™ (SC 5016, SC 5032) but it is only 1/8" in depth. When your project is on a tight budget or when you can get by with the minimal depth that will still provide a pressure break, MTI's Gravity Cavity drainage plane should be your choice. Gravity Cavity™ also comes in a "no-fabric" version for use behind siding. Gravity Cavity™ from MTI, the economy choice for drainage in the thin veneer rain screen building envelope!
Product installation instructions can be found in our Products section of our website. They can also be found in HyperSpecs. Many of our HyperSpec details have an installation animation on the main detail page. We also have installation videos for many of our most popular products on our youtube channel - youtube.com/mtidry.
MTi products are generally very easy to install. In thin veneer applications, Sure Cavity and Gravity Cavity drainage planes are simply rolled out over the WRB on the backup wall and temporarily tacked in place. Once the thin veneer (stucco, manmade brick, manmade stone, etc. is applied, the drainage plane is permanently held in place. Most of our weeps are rolled out onto the footing and the bed joint of mortar is placed on top of them. Simple and straight forward stuff.
Call MTI at 1-800-879-3348 or email us at firstname.lastname@example.org and we will be happy to give you a quote.
For lath attachment instructions please reference ASTM C1063–06 and the Northwest Wall and Ceiling Bureau's Field Technical Information.
For more information, visit "HyperSpecs® Wall Details. If you have additional questions, call 1-800-879-3348.