Multi-unit curbs provide the same service as single curbs, but with the added advantage of compact size and single roof flashings. They are used in applications where side-by-side service is best suited. Construction includes fully welded corners, factory installed wooden nailers, and dense rigid insulation. Custom heights may also be manufactured in a pitched roof style. Other options include pipe and duct sleeve caps, and damper shelves. Multi-unit curbs can be made in any of these three roof curb styles.