RUSS Strip – Things to Consider
RUSS Strip is a widely used accessory designed to reduce field seams while providing mechanical securement. It allows for continuous field membrane installation at locations where additional securement is required. This includes, but is not limited to, perimeter securement at walls, curbs, expansion joints, membrane securement in mechanically fastened systems, valleys, and any area where the angle change exceeds 2:12.
While RUSS Strip is highly effective in minimizing field seams, it’s essential to follow the manufacturer’s installation procedures to ensure proper performance.
6" RUSS Strip consists of a 75-mil reinforced EPDM or a 45-mil reinforced TPO membrane, available in 6" x 100' rolls. A 3" wide adhesive strip is factory-applied, taking up half of the RUSS Strip and aligned flush with one edge.
9" RUSS Strip (EPDM) and 10" RUSS Strip (TPO) are similar in construction but slightly wider, featuring two 3" adhesive strips that are flush with both edges. These wider options are commonly used for membrane securement on mechanically fastened projects to create perimeter sheets, while the 6" RUSS Strip is more frequently used at angle changes, perimeter securements, expansion joints, and other locations where securement is required.
This month’s Tech Talk outlines a few key guidelines to follow when installing RUSS Strip on your upcoming projects:
1) Primer Must Be Used in Lieu of Bonding Adhesive
A common misconception when installing RUSS Strip is that bonding adhesive can be used on the pressure-sensitive adhesive strip. However, Carlisle’s RUSS Strip accessories for both EPDM and TPO include a factory-applied pressure-sensitive splice tape that is only compatible with the appropriate primer for each membrane type.
Before installation, the backside of the membrane must be cleaned with Weathered Membrane Cleaner, primed, and then rolled with a silicone hand roller.
A factory-applied release liner covers the seam tape and can be removed just before installation to help prevent contamination. This liner allows bonding adhesive to be applied to the non-adhered side of the RUSS Strip, the wall substrate, and the backside of the wall flashing (excluding the area where primer has been applied), while keeping the seam tape clean. Once both the bonding adhesive and primer have properly flashed off, the release liner can be removed and the membrane installed.
Bonding Adhesive Cannot Be Used to Adhere the Adhesive Strip
Bonding adhesive cannot be used to adhere the pressure-sensitive adhesive strip on the RUSS Strip to the backside of the wall flashing. This practice is not accepted on warranted projects and could lead to premature failure—making it a potential weak point in the system and a costly repair down the line.
The same principle applies when using 10" TPO RUSS or 9" EPDM RUSS to create perimeter sheets on mechanically fastened projects or in any other application involving RUSS Strip.
Use only the appropriate primer:
HP-250 EPDM Primer for EPDM projects
TPO Primer for TPO projects
Low-VOC EPDM/TPO Primer for use on either EPDM or TPO
2) RUSS Strip Installation and Orientation
RUSS Strip must be installed with the adhesive side facing outward—toward the field membrane. It can be installed into either the vertical surface (wall) or the horizontal surface (deck). Carlisle will accept RUSS Strip installed approximately 4"–6" away from the wall into the deck. However, if it is installed into the wall, the bottom of the plate must be no more than ½" above the deck.
Installing RUSS Strip with the adhesive side facing the wall or perimeter can lead to performance issues. When installed backward, the edge of the 2" Seam Plate or Piranha Plate may tear the reinforced membrane during uplift, which could result in a system failure.
This is why proper orientation—with the adhesive side facing the field—is essential.
Please refer to the image below for examples of correct and incorrect RUSS Strip installation.
3) Appropriate Fasteners, Plates, and Fastening Rates
The selection of RUSS Strip plates and fasteners depends on the substrate and system type. In most scenarios, 2" Polymer Seam Plates (for EPDM) and 2-3/8" Piranha Plates (for TPO) should be used in mechanically fastened systems. Both plate types feature barbs underneath that help secure the membrane effectively, making them well-suited for mechanically fastened applications due to membrane movement.
2" Seam Plates can be used on adhered systems for both EPDM and TPO. They can also be used in mechanically fastened systems if the substrate is a hard or smooth surface. For example, 2" Seam Plates are appropriate when securing RUSS Strip to a concrete wall on a mechanically fastened system, as they seat more securely than Polymer Seam Plates or Piranha Plates in that condition.
Please refer to the Membrane Fastener Selection Tables below when selecting appropriate fasteners for RUSS Strip on both EPDM and TPO projects.
It should also be noted that the fastening rate for both adhered and mechanically fastened systems is a maximum of 12" on center (O.C.) at perimeter securement. This rate increases to 6" O.C. for all projects with warranties greater than 20 years or with warranted wind speeds exceeding 90 mph.
Please keep this in mind for future projects, as failing to follow the required fastening rate can result in costly repairs and added risk due to the increased number of penetrations created by the fasteners.
4) Other Things to Consider
RUSS Strip is not approved for use on PVC projects in conjunction with Carlisle’s 2-Step Activator and Primer.
EPDM RUSS Strip cannot be used on TPO projects, and vice versa. Always use the correct RUSS Strip based on your project’s membrane type.
RUSS Strip should be cut approximately 3"–6" short of any inside or outside corners during installation.
Excessive dust or debris must be properly cleaned using Weathered Membrane Cleaner before applying primer.
When jobsite temperatures fall below 40°F, heat the cleaned and primed membrane area with a hot air gun as the RUSS Strip is applied and pressed into the tape.
TPO and EPDM RUSS Strips have a shelf life of one year.
For any questions regarding RUSS Strip installation procedures, please contact Dane Helnore at CSL West.