Wagner Heating and Cooling
Small Residential HVAC Contractor
CSST Flex Pipe
A development of four two-story townhomes with unfinished basements built by
Pusey and Raffensberger. These 2,000- to 2,400-square-foot homes range in price from $285,000 to $355,000. Wagner used 1/2" flex pipe on a manifold to run gas lines between the main gas line and each unit's fireplace, duel-fuel furnace, and water heater.
Pennsylvania builders Pusey and Raffensberger hired Kevin Wagner to rough in and install a dual fuel furnace using heat pumps and natural gas for a four-townhome development. He won the contract largely because of his affordable bid. Wagner's bid was less expensive because he proposed to use CSST flex pipe for the gas line, which would allow him to complete the project faster than contractors using steel.
"I use flex pipes on smaller projects such as this one because it cuts down on labor time," Wagner says. "This project took about two-and-a-half hours to do everything, including the final touch ups and putting the manifold in. If I used black steel pipe, I would have had to thread the pipe, which probably would have taken me 4 to 6 hours."
"Overall, it costs less in materials to use black iron pipe and thread it, but when you factor the labor in, flex pipe is much cheaper since CSST is so much faster to install in short runs. However, if you're doing a long run, maybe a 100-foot straight length, flex pipe doesn't make financial sense since black iron pipe is pretty quick on straight runs."
"I ran about 60 feet of the ¾" CSST for the main line, and probably close to 60 feet of ½" line for the furnace, fireplace, and water heater lines," Wagner says.
"I put a manifold in the basement down by the HVAC unit so the homeowners could add lines if they remodel, but it doesn't really matter where you put the manifold. You don't even have to use a manifold. Instead, you can just put in t-fittings. You might save some time, but it's less handy in the long run than the manifold, which has extra spaces for future retrofits. You can also turn the main gas line off right there."
"Flex pipes come with all sorts of accessories, including the manifold and other fittings. Each manufacturer has a slightly different manifold, but they all have about four or five ports of ½" outlets, with one ¾" outlet for the main. Most are made of black iron."
"Materials probably cost about twice as much for the CSST as for the black pipe. For this project, they cost about $350. Flex pipe costs about $1.70 a foot, fittings are about $7 to $12 depending on the size, and the manifold costs about $27."