Typical costs: Costs for complete installation of an encapsulation system start around $2,000-$4,000, average $5,000-$7,000 and can go as high as $8,000-$14,000 or more, depending on the size and condition of the crawlspace, local rates, and the materials used.
The Rc thread is a designation for BSPT (British Standard Pipe Taper). refers to the threaded end of a fitting or pipe which is 1/4 inch trade size (not actually 0.25 inches), and having British Standard Tapered Pipe threads.
The UNR thread is a modified version of a standard UN thread. The single difference is a mandatory root radius with limits of 0.108 to 0.144 times the thread pitch. When first introduced decades ago, it was necessary to specify UNR (rounded root) threads.