Our home, like I think all Eichlers in the area, was originally heated with in-floor radiant heat.  Basically, the house is on a concrete slab and there are copper tubes running through the slab about 18″ apart throughout the whole house.  I should mention that since the tubes are copper (as opposed to steel or plastic) they have quite a long lifetime.  These tubes are hooked up to a pump and boiler- the boiler heats water and then the pump circulates water throughout the copper tubing system.  When we moved into our house, we still had the original (1958) tubing, boiler and pump in place, and we still do for the most part.  And I should mention that it’s a pretty nice way to heat a home- the air doesn’t get dry in the winter and our hard “cold-looking” floors are actually quite warm.  Given the age of the system and the relative inefficiency of our house though, it’s not the most energy efficient way to heat a home.  Also, there’s a significant “warm-up” time from when you crank up the thermostat to when the house is actually warm.

Before we moved in, we discovered during the home inspection that the copper tubing does not hold pressure, i.e. there was a leak somewhere in the system.  We could keep an eye on this by connecting a cheap pressure gauge (from Home Depot) to the system.  Given that we had much bigger fish to fry (a moldy crumbling garage, a leaky roof, etc.), we decided to put it off as long as possible.  Our interim solution was to open up the water source to the tubing, so that as water leaked out it was refilled.

The first issue we had with our heating system was with the boiler.  It originally had a pilot light that kept going out- so if it got cold and the thermostat turned on the signal to start the boiler, it wouldn’t actually start until we manually lit the pilot light with a match- it was just like not having a thermostat at all, which really sucks.  At the time we weighed the pros and cons of getting a new more efficient boiler vs. repairing the old one.  The efficiency of the new boilers compared to the old one (especially since it’s difficult to know the efficiency of the old one since a lot of the “lost” energy actually goes to heat the room around the boiler which isn’t otherwise heated) isn’t enough of an improvement that it was obviously beneficial to buy a new boiler.  Also, we sill had bigger fish to fry.  We decided on a “breaking point” cost (about $300 I think), so we would get an estimate for the repair and if it was above our breaking point we would get a new boiler.  Turns out it was about $5 below the breaking point, so we went for the repair. The repair involved having an electric starter added to the boiler and also had it cleaned.  So far so good (fingers crossed).

The next issue came up when we were renovating the hall bath.  After having removed the tile, we noticed a wet spot on the floor:

Given that we planned to paint the floor, we knew that we had to address the wet spot.  We were hoping that it was just a spill and would dry up… so we outlined it in chalk and waited a few days.  Sadly, the wet spot didn’t shrink.

At this point, we really had to do something.  There are actually two sets of water pipes running through the slab- the domestic water (for faucets, toilets etc.) and the radiant heating.  Unfortunately, you don’t know what the source is until you jack hammer the slab… but we had a strong hunch (given the age our of our house and stories from neighbors) that this was the radiant floor system.  We also realized that this probably isn’t the only leak, so the best approach was to hire someone to detect and repair all possible leaks in the radiant heating system.  After researching online (mostly through the Eichler Network) we chose to call Anderson Radiant Heating.

The entire process of detecting and repairing all of the leaks took about a full day.  We had about 7 leaks throughout our house, which is about average for a house of our age, according to them.  To detect the leak, the guys drained the water from the heating system, replaced the pump with a special pump and pumped helium through the system.  They then went around with a very accurate helium detector (like a metal detector) to pin-point the leaks.  They were actually pretty accurate (even through the tile and pergo flooring we have throughout the house), and luckily the leak in our bathroom was in fact due to the radiant heating system.   They marked the leaks and then jack-hammered around them, repaired the leaks, and re-filled the concrete.  Each repair was about 1-2 square feet in diameter.  They did NOT replace the flooring above the leaks, but they were very careful when they removed them (i.e. for leaks under tile, they removed full tiles so we simply had to find new tiles to replace the old ones, put some mastic down and then grout… which we haven’t gotten to yet over 2 years later).  They were also VERY clean.  Having lived through having our floors jack-hammered dozens of times, I know it creates a LOT of dust.  These guys were GREAT at minimizing the dust, in fact, I didn’t notice any more dust than normal after they left.

The cost was pretty high- but given the sophistication of their equipment and how quickly, neatly and accurately they work, I think it was justified.  Also, the cost gets more reasonable the more leaks you have.  Some of the costs are fixed (you have to pay for them to come out, hook up their helium etc, even if there are no leaks) and some are dependent on the number of leaks they have to repair (time spent jack-hammering and repairing individual leaks).  Overall, I think we paid around $2,500.  It produces a little peace of mind given that before they arrived, we  KNEW we had leaks and after they left we KNEW they were all repaired.  However, we never know when a new leak will start and when we’ll have to call them again.