Tuesday, January 31, 2012

Cap and Boots (III)

This marks the third post in this thread examining defects common to older homes in particular. I guess I'm trying to address a couple of questions:

-is an older home worth fixing up?
-what are the downstream effects of the way we build houses, and is there a better way?

So far I've looked at roofs and foundations in post 1, then wiring in post 2. Today, I'll, uh,  pipe up about another critical house system - the waterworks.

Plumbing.

The word plumbing relates to the Latin word for lead (plumbum). If you are looking for the atomic symbol for lead on the period table of the elements, you'll be looking for Pb, not L. It's number 82 on the table. Lead was a very common material for piping in years past.

Lead has a bluish white color when freshly cut, though this soon tarnishes to a dull grayish color with air exposure. Lead pipe is malleable and easy to work. It is also toxic to ingest lead, even in very tiny quantities. The ancient Chinese civilizations, along with the ancient Greeks and Romans, had documented lead poisoning problems. Here's a picture I found on Wikipedia of an ancient Roman lead plumbing fixture:


Lead water pipes were still in common use in the early 20th century and remain in many households. For some reason, the lessons of the ancients were not brought forward however this is an all-too familiar story hardly worth remarking upon. If your house was built before 1930, you can be fairly sure lead piping is present in the plumbing system. Repairing plumbing with lead piping is problematic. In the US, the Safe Drinking Water Act (SDWA) required that after June 19, 1986 only "lead free" pipe, solder or flux could be used in the installation or repair of public water systems, or any plumbing in residential or non-residential facility providing water for human consumption, which is connected to a Public Water System. More specifically:

"The law prohibits any person from introducing into commerce any pipe, or plumbing fitting or fixture that is not lead free after August 6, 1998, except for a pipe that is used in manufacturing or industrial processing."

In an older house, so long as the water is not soft or otherwise corrosive, the interior coating on the pipes from years of water moving through means that there is little likelihood of further lead leaching into your drinking water and poisoning your young children. Still, if you do have young children, or are planning to have them, (or a pregnant woman resides in the household) are you willing to take the risk? Blood and brain disorders are no fun.

If you have a problem in the plumbing and need it worked on, your plumber is going to insist that all lead components be ripped out and replaced. Lead is porous and very difficult to solder onto, and non-standard old pipe sizes make connections to newer equipment problematic.

An alternative to lead piping seen fairly commonly is galvanized water piping, especially in homes built more than 50 years ago. This form of piping tends to corrode over time from the inside out, especially on horizontal runs, and of course since the damage is internal it can present a nasty surprise. Last year I was working on a bathroom renovation in an old house in West Hartford CT, and the pedestal sink's drain tied into a 1.5" galvanized nipple coming out of the wall. In an effort to remove the fitting from the galvanized nipple, I sheared the pipe off - inside the wall of course. A case where a simple repair operation becomes more involved. I had to open the wall up to access the stack vent pipe, and a 10 minute task became a couple of days long and a lot more costly. The 1.5" nipple had rusted away on the inside, and that's why it shredded when I tried to unscrew the fitting. It's best not to underestimate what may be involved with repair work to older plumbing systems.

I'm not a plumber by trade, so can hardly claim true expertise in the area, however I worked as a commercial irrigation installer for much of my twenties, and have glued miles of PVC pipe and sweated miles of copper pipe. I feel quite comfortable working with plumbing fittings, however certain tasks are only properly performed by licensed plumbers.

Another problem associated to internal pipe corrosion is a build up of debris and mineral deposits in areas where the pipe interior becomes less smooth, build-ups which can eventually cause blockages. Often householders will deal with blockages by pouring caustic chemicals into their system, which, though it might clear the blockage tends to accelerate the damage to the interior pipe wall, further exacerbating the problem.

Even new plumbing piping is not always a bonus. Between 1978 and 1995 polybutylene piping was commonly installed, and this has proven to be a disaster. The majority of leaks begin to make their appearance 10~15 years after installation. Apparently the presence of chlorine compounds in water will cause deterioration in the internal structure of the plastic and its fittings. There was a massive class-action lawsuit, Cox vs. Shell Oil, which lead to a $1Billion settlement. Building codes in both Canada and the US now prohibit the use of polybutylene piping and fittings in new construction.

Finally there is the stack vent pipe itself, which is designed to help the entire drainage system function. The modern standard is a 3" pipe, however older homes often have smaller vent pipes which do not allow the system to drain properly, and this in turn can contribute to the formation of blockages on the inside of pipes. It's like they develop atherosclerosis - and the heart attack may indeed come when you find out the cost of replacing these aged piping systems. Think about this too in regards to replacing a toilet with a low flow toilet - if the vent piping is too small, the draining will be less than ideal with a low water flow, and this is possibly going to engender other problems in the system, especially blockages.

The bottom line with piping is to go with copper if you can afford it. Nothing beats copper, and if current metal commodity prices continue in the upward direction seen in the past few years, that copper piping could be an alternative investment to buying other precious metals. You may have to protect it with a gun however. I'm only sorta joking.

Old plumbing fixtures are a mixed bag. They tend to be of much higher quality materials than new fittings and are generally fully serviceable and rebuild-able - if you can get the parts. Old toilets though are water hogs and there's no argument about the benefit of replacing them, especially if your water is metered and you live in an area with water shortages. If the porcelain on the old bathtub is in poor shape the cost of refinishing is a bit daunting. Old faucets, while of good materials and rebuild-able, often lack the flow rates of modern units so they may disappoint. Further, old faucets are not often ADA compliant, with extended lever handles, and thus many people can have difficulty operating the older faucets.

Cast iron sinks and and tubs from yesteryear are significantly stouter than their modern counterparts, and even if you choose to remove them, you'll get some good money for the scrap cast iron. Personally, I've always preferred sinks with the faucet mounted on a vertical surface rather than a horizontal one - this is what I've seen in at least some hospitals, presumably as a means of reducing places for germs to hang out. You want horizontal surfaces, where water will sit, to be easy to wipe clean. For some reason however, most modern sinks have provision for the faucets on the horizontal surface and obtaining wall-mounted faucets is becoming a little more difficult, at least from what I've observed in the plumbing display at local home improvement center. So, you may need to special order. Wall mounted faucets also have the advantage of freeing up counter space, and this gives a more streamlined look as well.

As a final point in regards to plumbing systems, if you are designing from new, it is well worth taking the time to design the plumbing system, especially the piping, so that it can be accessed for repair and modification. Think about how the pipes may have to penetrate other structural members and design so as to have as few penetrations as possible. Design so that there is room for more piping to be added in key areas if need be. Think ahead. Think how the building is going to learn - how likely it it might be that it require some modification 10 or 15 years down the line. Make sure the main water shut off for the house is easy to get to so that in an emergency the water can be shut off as soon as possible. 

In the next post I'll take a look at old house systems in terms of the materials used. Thanks for coming by the Carpentry Way.

No comments:

Post a Comment

All comments are moderated, so if you're planning to spam this, know now that your clicking and pasting is in vain. I do read the comments before posting, so your mission is doomed from the outset. All this time and effort trying to put your inane spam onto blogs -- is this how you want to spend your time on earth?

Please do me the courtesy of appending your name to your comment, even if posting under the 'anonymous' option.

Comments NOT accepted include:

-those containing links unrelated to blog content
-spam of any kind, or ham for that matter
-did I mention that attempted spam postings will be non-starters?