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Author	Comments
Steven Wollmann Posted: Sep 23, 2011 01:32 PM	Bidding on spraying a trench I have sprayed buildings and most flat surfaces. Need to do a quote on spraying a waterline trench. Is there a Ballpark figure formula out there. Charge by stroke? Linial foot? Cubic foot? What do you guys use. All help apprieciated.
Circle-D Posted: Sep 23, 2011 09:37 PM	I charge by the meter in a situation like this.I spray a lot of pex tubing for the outdoor wood boilers.There are a supply and return line in the same trench a few inches apart. I encapsulate with approx 2 1/2"- 3" of foam around the tubing. It generally comes out in the $9-11$ per linel foot area. This is considerablly cheaper than the factory insulated tubing that goes for around $13 to $22 per foot. The factory stuff only has 3/4" of foam around the pex.
steven argus Posted: Sep 25, 2011 09:22 PM	Yup, what Skip said. If you're not doing the digging, make sure they give you a nice trench to work in. At least 24" wide, dry - virgin subsoil (no settling allowed here, just like a footer) and no major roots sticking out of the trench wall.
steven argus Posted: Sep 25, 2011 09:29 PM	As far as cost goes, don't get caught in the T&M trap for a small job. You should have a minimum daily $ you need to be at to reach a profit. Just charge that, at least. if the job is at least 200', it's gonna burn up most of the day anyways.(weather, prep, cleanup, coffee, etc.) remember, the preinsulated lines from the factory are a lot more $$$ and less foam is used. And don't forget to use the O2 barrier tubing.
john rogers Posted: Nov 26, 2011 08:25 PM	please advise us. what is the O2 tubing all about? thanks
John Shockney Posted: Nov 27, 2011 06:13 AM	Motor City, All hot water heating systems should only use oxygen barrier PEX or other approved tubing. Regular PEX tubing is actually porous to small molecules like oxygen and this O2 from the air can travel into the water adding oxygen to the water. The added O2 presents a problem in a heating system due to the iron and steel components in the system by causing rust (iron oxide) to form inside the system. This causes premature failure of the steel or cast iron components by either leakage or blockage. Use of unapproved tubing will void the warranty of most major boiler manufactures though most of these “wood Boiler” companies don’t warranty their product long enough and don’t care what type of tubing you use. But when I install any hydronic heating system I always use O2 barrier PEX also called “B” PEX and I don’t use any of those hoes clamp type connectors ( they leak) I only use the full circle copper crimp ring. Also separate iron and copper components with proper insulated unions to prevent electrolysis. Thanks Airpro Airpro Heating and Air Conditioning

Author

Comments

Steven Wollmann

Posted: Sep 23, 2011 01:32 PM

Bidding on spraying a trench

I have sprayed buildings and most flat surfaces. Need to do a quote on spraying a waterline trench. Is there a Ballpark figure formula out there. Charge by stroke? Linial foot? Cubic foot?
What do you guys use. All help apprieciated.

Circle-D

Posted: Sep 23, 2011 09:37 PM

I charge by the meter in a situation like this.I spray a lot of pex tubing for the outdoor wood boilers.There are a supply and return line in the same trench a few inches apart. I encapsulate with approx 2 1/2"- 3" of foam around the tubing. It generally comes out in the $9-11$ per linel foot area. This is considerablly cheaper than the factory insulated tubing that goes for around $13 to $22 per foot. The factory stuff only has 3/4" of foam around the pex.

steven argus

Posted: Sep 25, 2011 09:22 PM

Yup, what Skip said. If you're not doing the digging, make sure they give you a nice trench to work in. At least 24" wide, dry - virgin subsoil (no settling allowed here, just like a footer) and no major roots sticking out of the trench wall.

steven argus

Posted: Sep 25, 2011 09:29 PM

As far as cost goes, don't get caught in the T&M trap for a small job. You should have a minimum daily $ you need to be at to reach a profit. Just charge that, at least. if the job is at least 200', it's gonna burn up most of the day anyways.(weather, prep, cleanup, coffee, etc.) remember, the preinsulated lines from the factory are a lot more $$$ and less foam is used. And don't forget to use the O2 barrier tubing.

john rogers

Posted: Nov 26, 2011 08:25 PM

please advise us. what is the O2 tubing all about?

thanks

John Shockney

Posted: Nov 27, 2011 06:13 AM

Motor City,

All hot water heating systems should only use oxygen barrier PEX or other approved tubing.

Regular PEX tubing is actually porous to small molecules like oxygen and this O2 from the air can travel into the water adding oxygen to the water. The added O2 presents a problem in a heating system due to the iron and steel components in the system by causing rust (iron oxide) to form inside the system.

This causes premature failure of the steel or cast iron components by either leakage or blockage. Use of unapproved tubing will void the warranty of most major boiler manufactures though most of these “wood Boiler” companies don’t warranty their product long enough and don’t care what type of tubing you use.

But when I install any hydronic heating system I always use O2 barrier PEX also called “B” PEX and I don’t use any of those hoes clamp type connectors ( they leak) I only use the full circle copper crimp ring.

Also separate iron and copper components with proper insulated unions to prevent electrolysis.

Thanks
Airpro

Airpro Heating and Air Conditioning

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