The initial material cost differences between copper and plastics are significant. A article comparing costs for different plumbing pipes can be found here: http//:www.southce.org/ajwhelton. A US government funded study to investigate what chemicals leach out of American plastic plumbing pipe is also underway. Go to that same web page and type in 'plastic pipe'. There has been quite a bit of work done in Europe but American materials have not been equally publicly scrutinized. Some of the study data has already been released and testing included actual buildings and testing of new pipes purchased at local building supply stores. Here is a link that might be useful: Informational research website

First reinforced gypcrete can be as thin as 1-1/2" however, the flooring it goes upon must be stable and often additional 3/4" plywood must be added, thus you end up with possible 2-1/4" of depth. Staple up is a viable option which usually requires transfer plates below, additional insulation to create barrier and is more labor intensive with the routing. Typically there is no noise associated with this method as long as expansion is allowed as PEX can grow several inches over 100Â. As long as holes through joists are big enough, swing joints are left and plates are secured well, I have never heard any noise from a sub-floor that has been glued and nailed. Note on an average home many times it requires at least ½" PEX for underfloor installs due to additional BTUÂs per lineal foot to transfer heat to conditioned area. Any contractor or distributor with experience in this and has a computer program can run the numbers that provide heat loss, tube sizes, lengths of circuits, GPM, water temp and more. While a warmboard is on the expensive side, is a great product when installed properly and usually allows lower water temps and smaller tubing, like 3/8" versus the staple up options. There is nothing wrong with ThermalTrack; it was developed as an option to warm board which was the first product on the market by Wirsbo, now Uponor. It usually comes in squares with routing options, and it is laid like a puzzle. Glue to floor and screw to joists is the key to a good install. Besides Warmboard type options there are even better applications such as Raupanel which are more money but can add value since temps can be even lower and floors quieter. This over all is the most expensive option since it involves a lot more aluminum for heat transfer and without buying there wood a person with a saw to rip all the sleeper boards. http://na.rehau.com/construction/heating...plumbing/radiant.heating/raupanel.shtml Being a former resident of the cold north, and having Radiant floor, there is no substitute. Besides the floor, the heating appliance is the next biggest choice, because unless you will be producing domestic hot water, the temps delivered to the floor will range between 75-135, depending on load, room, outdoor temps, flow, etc., so a condensing boiler is the perfect fit in this application to appreciate obtainable efficiencies.

Compatibility. There are many different PEX solutions out there and the components may or may not be compatible with each other. Availability. Local availability can be hit-or-miss. The manufacturer that the local big box considers its darling this year might not be the same months or years down the line. This feeds into the compatibility issue above. Initial cost. Crimpers and expanders (depending on which PEX solution you go with) are more expensive than a torch, flux, and solder. Support. If things get hairy and you have to get a professional in, it might be harder to track one down who is familiar with the PEX manufacturer you chose. Tasty goodness. Mice can't chew through copper. That being said, I redid my house completely with Wirsbo PEX. Nothing but love for it.

You are to slide the ring all the way onto the tubing so that no more than 1/16 of an inch of the end of the tubing is exposed passed the ring.........make sure that you spin the expansion head 1/4 turn between each expansion or else you will end up with leaks(unless you have the new battery operated tool that automatically spins the head for you)