Water Collecting Under Wall Below Navien Tankless Hot Water Heater

We've noticed water collecting under the baseboard below the Navien Hot Water heater. The problem is intermittent; it isn't constant, and it's a small amount of water. We've noticed the water collecting during the day, when water is being used in the house, and when the heating system is more likely to be running. As an example, there was water on the floor along the baseboard yesterday. The water had dried up overnight.

Although the water is below the tankless hot water heater, it isn't coming directly from piping on the hot water heater itself. We've checked the hot and cold water piping, the drain, and cycled the pressure relief valve (in case water is splashing), and found no leaks. The water is definitely collecting inside the wall.

Water is collecting along the baseboard below the Navien
tankless hot water heater. Notice the vent on the wall.
Cold air pours through this vent during the winter.

The water runs all along the baseboard.

Drains (black), main water (blue), and plumbing
for the tankless hot water heater

Drain pipes

Intake and exhaust for tankless hot water heater. Line above
white pipes is HVAC power and condensate drain.

Exhaust goes into garage

and up garage wall

up through roof

Installation of vent ducting.

Installation of Navien tankless hot water heater.

Navien tankless hot water heater as it stands
today. Line above system is condensate drain
from furnace and power to HVAC units outside.

Condensation line exiting storage room to outside under deck.

Condensation line drain by AC unit.

Given the situation, the best guess as to the nature of the problem is condensation forming on the cold water pipe inlet coming to the Navien unit from inside the wall. There's also possibility of condensation forming on the exhaust pipe from the unit.

Pipe insulation can prevent condensation forming, as the surface temperature of the insulation will vary from the surface temperature of the pipe. Condensation will not occur, provided that (a) the insulation surface is above the dew point temperature of the air; and (b) the insulation incorporates some form of water-vapor barrier or retarder that prevents water vapor from passing through the insulation to form on the pipe surface.

Of course, another possibility is a slow leak in one of the water lines. The fact that the problem just showed up in the winter cold weather seems to mitigate against this, but doesn't rule it out.

Warranty Claims

Our agreement with Talon Homes, Inc., calls for us to wait 11 months before pointing out any non-emergency faults in the new home construction that require correction. These some of are the items we included in our email to Talon.

Left garage door guide bracket pulled askew due to the bolts coming loose.

This is caused by nailing together 2x4s instead of using 4x4s (see below)

Framing basement.

Looking down on top of deck pillar, showing it to be unfinished.
This could let moisture penetrate and potentially cause problems.

Footings of deck pillars were not finished.

Glass on door to deck is scratched.

Porch has settled leaving cracks where it abuts to house.

Cracks around front porch.

Weather stripping on front door has gap at bottom letting in draft.

Adding partial strip doesn't work, as it pulls away with opening and closing of door.

Paint on solar tube dome is chipped.

Cracking of window frame in upstairs, hall bathroom.

Crawlspace vents are flimsy plastic. Several have already blown away.

We also had a leak in the downstairs storage room due to poor plumbing workmanship, ridge roof tiles blow off due to improper length of roofing nails, and the door to the master bedroom sticking due to the house settling.

None of these items were addressed by Talon Homes.

First Christmas in Our New Home

Roof Problems

Roofing was installed October 3, 2010. On October 3, 2011, it was discovered that the roof tiles covering the vented roof ridge were not anchored properly. Portions of the roof had been blown loose, and further damage was likely as winter weather progresses.

I called the contractor, Talon Homes, and, since they were on their way to North Dakota, they asked me to get a roofer to take care of the problem, and either bill them, or if I paid for the work, they would reimburse me.

I was able to arrange repair by getting a referral from Doug Feser, who is building a spec home across the street. He will be using C&C Construction to do his roofing, and he called them for me. Aurelio "Ral" Ceniceros came out the same afternoon to take care of the problem. He brought a helper, borrowed roofing material from another job, and finished the work in 1.5 hours.

The photos below show the problem and the work done to repair it. It's been raining ever since they did the work, and we feel very lucky that we got this taken care of so quickly.

Roofing tiles along vented ridge 

Loose tiles

Open roof

Roof tiles loose all along ridge

Nails not anchoring tiles

Removing loose tiles

Roof ridge looking east to west

Roof ridge looking west to east

Nailed vent in roof valley. This is bad practice, because rain
or snow collecting in valley could cause leak at nail hole.

Original nail used is on right

Stained Concrete Finally Sealed

D&S Concrete finally put the sealer on the stained concrete walk and porch they poured last winter. Although they sprayed rather than rolled, as they'd promised, it appears they avoided collateral spray on the landscaping trees and shrubs. We'll see how the foliage holds up over the next several months. One thing I know now, I'll never use D&S Concrete again; too many problems (and here).

D&S Concrete Won't Finish the Job

We've been in our new house 4 months now, and examination of the stamped concrete front porch, walk, and driveway borders reveals fading, mottling, and small cracks. I attribute this to the subcontractor, D&S Concrete, failing to seal the stamped concrete. It should have been power washed and sealed as soon as weather permitted in order to retain color and prevent cracking. Despite sunny, warm weather, and many, many calls to Steve Solano of D&S Concrete, this simple procedure has yet to be accomplished. At this stage, some methods of restoring the concrete color and then sealing it may be required.

Original drawing for front porch and walk design

Framing porch

Porch poured

Framing walk

Framing walk

Walk being poured

Walk poured

Front walk in June not yet power washed or sealed

Dull look of stained concrete walk

Mottled driveway border due to not being sealed

A properly washed and sealed walk should look like this

June 12, 2011; 3302 Four Months Into Occupancy

EXTERIOR VIEWS

INTERIOR VIEWS

Entry

Upstairs Den

Entertainment Center of Great Room

Looking into the dining area of the Great Room

Dining area of Great Room

Kitchen

Looking from kitchen through Great Room

Stairway

Wetbar

Recreation Room

Wetbar off rec room