bg, It doesn't have to be a copper tee, but if it is what you bought so be it. Make sure that you have a male or female NPT on your outlet port. Cut a piece out of the copper main that is not wider than the width of your outlet port. slightly bend one side of the mainline and slide the end fitting and gasket on the one side all the way on, do not tighten. Slide the second end fitting and gasket on the opposite side. Then bend the pipe back in line with other side of the mainline and center the tee. Slide the gaskets and end pieces onto the tee and tighten down with a wrench. Screw a cap plug to the out let port of the tee and test for leakage. Tighten anything that leaks. When that past leak test. Unscrew cap or plug and install a threaded nipple if female or a threaded adapter if male. Then attach a ball valve to be able to shut off the entire irrigation system if there are repairs to be made later but most important you can turn back on your mainline to the house and continue working or your system at your convenience. I would do everything in PVC because it is easier and more convenient to work with. Make sure you pt concrete or something that can withstand thrust at all 90 degree bends. JMHO. Aloha

I'm assuming you're talking about copper water tube. Type M copper tube is the thinnest grade for water supply and that is only available in a hard drawn grade which would kink if you tried to bend it even a little even if it was filled with sand. Type K and Type L is available in a soft drawn type which is bendable, however, these soft types are often sold in coils which must be unwound into a straight length, and they may be too flexible for your purpose, or just look funny since you won't be able to get them perfectly straight. You could however, take a piece of type M and heat it to almost cherry red with a torch in the area you want to make your bend. When you get it heated, you need to cool it quickly in a tub of cold water. This will soften the tube so it will be easier to bend without kinking. I don't know how tight of a bend you want, but that's one thing you could try for your project. You will probably need to polish the copper after you do this since it will discolor it where it is heated. GG

Thank you for your considered and thoughtful responses! As far as explosive sewer gas, appreciate the warning but, as stated, already torched the vertical "tailpiece" and removed it. With respect to fernco fittings, I looked at these and found eiher a no-hub "sleeve" type connection or a "donut" which fits inside existing pipe. Doesn't seem the no-hub sleeve would provide the stability you would want and, at any rate, it does not fit over the coupling (hub) on the closet bend. The donut is designed for cast-iron pipe and will not fit in 3" coopper hub. Box-store people had no idea how to fix this as they are familiar only with cast-iron or PVC setups. I bought a new copper flange and was lucky enough to bump into a plumber at the supply house who gave me a few inches of 3" copper (10' of 3" is super expensive!). I resoldered this new "tailpiece" into the existing closet bend with my little propane torch (sorry again about torch and sewer gas, but too late). Hoping and praying that this joint holds up. Now I need to attach new copper flange - now you've got me worried about soldering it on. Hope anyone else who has to deal with refitting to copper closet bend can benefit from your comments.

"Is it necessary, or a good idea to replace the areas of the house that were not included in the remodel, since the house is 25 years old since it is M copper?" Yes, do a total replacement, as the copper has reached it expected life expectancy. CPVC is widely used in mobil homes due to it's flexibility and lack of out-gassing at the glue joints. "Also, the plumber wants to use several island vents, including one in a bathroom. He doesn't want to go through the roof." You need to have a short and serious chat with your contractor about quality of workmanship, because this is BS. "And yes I think this is all about the general contractor saving money, my husband is afraid that if we push him too hard about the pipes he will charge us more on change orders/items that he has completed, but will not give us a price on." In many states all change orders are required in the business and professional code, to be fully priced upon presentation for signature. But, why would you sign an authorization to proceed, without knowing what it cost? "We ask him how much adding or changing something will be, instead of telling us he just builds it without giving a price or change order. We have asked him several times to write it up, but he does not, Its really irritating and yes my contract states that he must give us the change order in witting, before he changes anything." If you know an attny. better yet where he lives, don't wait until monday, race over to his house and break in.