Ever thought a lot about your plumbing?

And no, I don't mean your personal plumbing, I mean the pipes that carry the water in and out of your house.

The past few weeks have had me thinking a fair bit about plumbing (amongst many other things). From the time when I heard that the City of Vancouver was giving us the opportunity to upgrade our own sewer and water pipelines to the tune of $13,000, to the decisions about PEX vs. copper vs. ? and ABS vs. PVC vs. Cast iron, etc., there are a lot of things to consider when it comes to simple "pipes". So what have I learned from all of that? Well a  few things:

1) PEX, for those of you who don't know, is "cross linked" (thus the "X") high density polyethylene (HDPE, thus the "PE") or for those of us in the realm of "simple knowledge", a #2 on your recyclables. It is food grade and generally considered safe, but there seems to be some level of discomfort in the literature out there as to whether or not it is carcinogenic or not. California had a long, disputed battle between different parties on the PEX front as PEX was not allowed in the State's plumbing until 2009. While the conclusion of the debate was that it posed no significant health risks, there is still some debate on the topic and the long-term health effects of PEX piping are still somewhat unknown: http://www.builderonline.com/legislation/californias-pex-battle-continues.aspx While it's more than likely safe, and has been used in Europe for decades, there are many confounding factors, such as whether it is exposed to UV (which degrades the plastic...which makes you wonder about #2 bottles kept out in sunlight!?) or whether the plastic is exposed to chlorine (which most water supplies are).  PEX also emits VOCs and can add strange taste to water (apparently). On the plus side, it's easy to install, and generally has lowered embodied energy and can even be colour coded. And I've been drinking from it for the past 4 years (maybe longer?). So...hard to say...but what are the alternatives?

A picture of PEX tubing (blue for cold water, red for hot water!)

Well - the "tried and tested" answer is copper. Naturally antibacterial, copper has been used in houses for a long time and seems to be safe when used with non-leaded solders (plus can be recycled). However, copper does have significant impacts in terms of its mining (albeit so too does oil!), is more expensive, and copper toxicity can exist.

Option #3 is to use polypropelene (PP, or a #5 on your recyclables). PP is more temperature resistant than PEX, can be recycled and altogether seems like a safer plastic. It has a fair bit going for it and is a contender at this point, though one must it into context in a world FILLED with plastics (and who knows what is in other parts of the water system, right?).

Green Building Advisor - perhaps the best resource I've found in my house journey thus far - has some good discussions on this, but the conclusion is definitively inconclusive!
http://www.greenbuildingadvisor.com/blogs/dept/qa-spotlight/how-safe-pex-tubing
http://www.greenbuildingadvisor.com/community/forum/green-products-and-materials/18789/pex-tubing


All said and done...I think I'm going to install a carbon block water filter in our kitchen which should help to cut out all of the nasties in whatever water we have. Something like this.

PVC is another material (#3 on your recyclables) which is generally nasty stuff (to manufacture, it offgases VOCs, etc.) I've made the decision to try to cut it out of the house wherever possible. It's one of the "banned" substances in the Living Building Challenge, and those behind the LBC tend to be out ahead of the curve and I trust them to be on things like this. It's nasty to produce, it offgases a lot (which affects indoor air quality) and just is a product that should be eliminated from human use in my opinion. So, we're trying to get rid of it...and instead using....another plastic! ABS, or Acrylonitrile butadiene styrene or (C₈H₈)_x· (C₄H₆)_y·(C₃H₃N)_z) is another thermoplastic...pretty benign except (like the rest of them) when burned. 


Oh - and apparently cast iron is way quieter for flushing toilets (albeit more expensive).


Lastly - have found this gal on the North Shore who was recommended to me by the mechanical company that we're likely to go with (Westwood Mechanical).


Other plumbing related notes: will likely do a Navien CH-240 Combi boiler (which in english means that I will be using a combined "boiler/hot water tank" system that provides the house's hot water for domestic use as well as in-floor radiant systems, all in a nice little box (no separate hot water tank, no boiler). It's space efficient, energy efficient, and if you're so inclined, allows you to have unlimited hot water showers (very non-green of me to say). We considered a Viessmann Vitoden 100 system (German) with an on-demand hot water attachment, but it's an extra $3000 and bang-for-your-buck, you're better off with the Navien (Korean...hey, their cars are beating out BMWs and VWs these days as well!). We're also looking into using radiant hydronic baseboard heat for the upper level of the house which actually is hidden in standard baseboards (no ugly radiators, plus its radiant versus convective heat). I also considered an air-to-liquid heat pump, but opted against it in the end...think I might have mentioned this before....since my mind is fading, I better call it quits for tonight.