Zilla® Double Stud XL In Step With RMI Efficiency Recommendations

New research from the Rocky Mountain Institute (RMI) finds that several features offered by Zilla’s Double Stud XL Flashing are key to reducing solar installation costs.

New research from the Rocky Mountain Institute (RMI) finds that several features offered by Zilla's Double Stud XL Flashing are key to reducing solar installation costs.


The RMI and Georgia Tech Research Institute report found that, in the United States, the median installation labor cost for a rooftop system is $0.49 per watt. However, in Germany, the median installation labor cost is just $0.18 per watt.

Why the difference? Researchers identified several factors that have helped the Germans install systems more efficiently. Incidentally, many of their recommendations align with existing features of Zilla's Double Stud XL Flashing, including:

Elimination of rafter identification. Installing bases for racking systems costs a median of $0.05 per watt, and the time and effort required to identify rafters is a big part of that. With Zilla's Double Stud XL, no rafter location is required, eliminating the need for installers to crawl through attics, drill test holes, or reinstall flashings when structural members are missed. Double Stud XL fasteners don't even require pre-drilling, another time saver.

Standardization of design. The report encourages racking manufacturers to develop pitched residential rooftop applications that eliminate the need for pre-installation prep work. The Double Stud XL already does this. Because rafter identification and marking aren't necessary, layout dimensions can be exactly duplicated from one project to the next, regardless of the underlying structure.

Move to one-day installations. Installing a system in a single day eliminates the costs of loading up and traveling to a jobsite and also allows installers to take on more projects and increase profitability, the report found. Thanks to its efficient design, the Double Stud XL installs quickly, making one-day installations possible in most cases.

To learn more about the time- and cost-saving benefits of Zilla's highly efficient Double Stud XL Flashing, contact us today!

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