AHP Project, Day 7

Note: the following is not a comprehensive listing of all the details involved in a full audit.  It's meant to be a general description of the process so please don't think that you can read this and do one yourself.  Your and the homeowners' safety requires a full Building Performance training, at a minimum.



John and Jane are delightful. Pretty much your ideal clients: interested in not just the audit findings but the process itself, close by but not in the way, curious and open to learning about efficiency and building science, and John makes good coffee. Sweet. After getting a copy of their utility bill history, something I prefer to have beforehand but was unavailable til today, and a friendly meeting to check in about any issues and to let John know the logistics of the day, we were ready. Start my personal CO meter and clip it to my belt, make sure I have spare rechargeable batteries for everything, clip blank forms to the clipboard, turn my phone ringer down, and think through the day in my mind. Move all the equipment onto a pad in the living room and decide we will wear socks instead of booties over our shoes.  My helper for the day is Dilip Sinha, an intern breaking in to the business. Though mentoring can be time consuming, it's also gratifying and a way to give back to those who helped me when I was just beginning.

At 8:30, it's still brisk out and warm inside so a quick tour through the house with the IR camera clearly shows a few insulation problems. The ones in the attic, R19 with the normal mediocre installation, should be easy to fix. The ones in the walls are what they are, impossible to repair without serious demolition. The floor is uninsulated. Even before we set up the blower door, it's easy to see the rays of cold air streaming in under the french door shoes and along some of the baseboards so I know that will be even more obvious later.

First, safety checks and Worst Case CAZ (combustion air zone) test. The FAU (forced air unit) is a 10 year old, 80% Carrier downdraft with powered vent. It's big. 93Kbtu output. Way oversized for this 2200 square foot house and a perfect example of how we used to think: the solution to almost everything is a bigger system. It shares a vent with a standard 40 gallon DHW (domestic hot water heater), then passes up through the attic and out the roof. In this house, both are in a closet in the middle of the house, behind double hollow core doors with no weatherstripping. Further, there is a 4X14 vent in the ceiling of the closet, no vents in the floor, and a 2X14 vent into the living space in each door. Two immediate problems: the total size of the air vents into the closet is considerably undersized for combustion air for both appliances and much of the combustion air is drawn from inside the house.

When both appliances are off, air from inside the house flows through the door vents and up into the attic through the ceiling vent. A quick peak behind a receptacle cover plate shows no insulation in the walls between the closet and the adjacent bedrooms.  And later, when the attic has warmed up in the sun, the blower door shows warm attic air being drawn into a bathroom next to the FAU closet *under* the wall between them! Common practice 50 years ago but poor from an energy and indoor air quality viewpoint. So the tests: the FAU passes easily since the flue has an excellent draft and the DHW would pass except that it has a flat plate under the draft hood, meant to reduce standby losses, that causes significant spillage of combustion gases. The whole concept of a DHW and an FAU in an uninsulated, poorly vented closet in the middle of the house is a poor one and is no longer even legal.
One final thing: the entire return duct system in the attic has no insulation at all. Nearly 100 square feet of duct surface exposed in the attic with an R value of 0. The heat loss or gain is substantial. All this goes into the report.

Next, the blower door test. Since all the exterior doors are french doors, including the front door, I decide to put the blower door into the door to the garage and open the main garage door. Start the pressure at -10 pascals, make one more trip through the house to make sure the wood stove inlet is closed tightly (a messy disaster if it's not) and to check all windows and doors, then run the pressure up to -50 pascals. 3365 cfm50. Moderately leaky and about what I'd expect for a 40 year old house. Drop the pressure back down to -20 and take John on a tour through his home with the IR camera. There's nothing quite like watching a homeowner clearly see where air is streaming in under baseboards, around sink plumbing in the wall, recessed ceiling fixtures, and through switches and receptacles. It's difficult to say no to air sealing the shell when the air infiltration is right there in full color. A moment of mea culpa: an unusual cold area in a bath, while touring with the IR camera, shows that I missed a window being open a crack behind a curtain. At least I caught it and redoing the blower door test yields a new and corrected number of  3110 cfm50. Check and recheck.

Now for the duct test.  John has replaced the ducts a few years ago because of rodent damage so I'm hoping for a low number and the test shows 255 cfm50. This calculates to 13% leakage, which is fairly good when I calculate for the oversized furnace which should have 2000 cfm of flow. But the true measurement of the flow with the furnace fan on shows 1050 cfm, only half what it should be. This is another all too common problem. Undersized ducts that are partially kinked somewhere in their length, creating enough back pressure to cut the flow in half. Using the true airflow rather than the 'should be' airflow shows a 24% duct leakage, quite significant. One thing I noticed, within a minute of the FAU shutting off, the floor registers showed up as blue or cold, indicating that crawlspace air was being drawn into the leaky ducts by the normal stack effect.Too bad John's paid to have his ducts replaced already because they need some serious attention. One final point to notice: the high water lines on the pier blocks in the crawlspace. Wow, there's some serious flooding during the winter. In fact, and this photo doesn't show it well, it touches the bottom of the supply plenum in the distance.

Last, Dilip does a full take-off of the house, measuring each of the outside walls and windows. Tomorrow, I'll enter all this information into EnergyPro software and model John and Jane's house. With a few tweaks and adjustments, it should tell me roughly how much each of the upgrade features I plan on suggesting to John and Jane will reduce their utility usage.

Five hours later, we're packing up the final bits. Tomorrow, I have the day blocked off to write John and Jane's report. I have found, from talking with other Home Performance Contractors, that I'm slower than most when it comes to auditing and writing up the report. So be it. My belief: it should take as long as it takes to do it right.

Willowside Project, Day 6

The batteries are charged, camera's in the truck, and the blank forms are in the briefcase.  Two of us will arrive at John Doe's at 8:30 tomorrow - Wednesday - morning.  It should be a brisk and partly cloudy day, enough difference between inside and out to get good, clear IR camera pix.  First a short sit-down with the owner, then quick walk through with the camera, a Worst Case Combustion Zone test (let me know if you want more info on that; I'm may write a post about why it's vitally important), a blower door test, duct pressure test, and lastly a complete sketch or take-off of the house so we can correctly computer model it.

Looking forward to it.  It should be a fun one.  I'll take plenty of pix.

Comments are enabled and so feel free to ask question or post suggestions.  In this new field of Building Science, or House-As-a-System, we're all learning from each other.

Willowside Project, Day 1

I have an idea: I'm going to take the job that just came in today and blog it from beginning to end, Day 1 til Day X, every step of the way. Initial call, initial visit, second visit & audit, 3rd visit & report delivery, on through contract phase, our local PACE program called SCEIP - Sonoma County Energy Independence Program - approval, Energy Upgrade California approval, permitting, doing the work, final approvals, disbursement and final check. I plan on giving details. What worked, what didn't, where I messed up, where I nailed it. And since I'm not a company who does 5 or 10 projects a month but a relative small fry with a small crew and a small budget, perhaps you'll find nuggets here that you can use to make *your* business more successful, or at least to avoid whatever pitfalls I end up blundering into.

There'll be days, sometime several in a row, where nothing happens. That's the way it goes. I haven't received the approval of the homeowner yet so I'm going to start him out as John Doe on Anywhere Road, but I will tell you it's in Santa Rosa, California, 95401, and if he/she allow it, I'll be more specific. Perhaps there's other Home Performance Contractors who've already done this but I haven't found them so hang on, here we go.

Day 1
While cleaning up from an EUC (Energy Upgrade California - if you don't know what that is, Google it) 3rd party verification at another just-finished project in the country outside of Santa Rosa, the phone rings. A guy with a pleasant voice and just enough accent that it's hard to understand him outdoors speaks and says he got my number from a local solar electric vendor who I sometimes work together with. And that the solar vendor already did a site survey, sized the system, and mentioned that perhaps John should consider getting some efficiency work done to his home, also. That the 6kw +- solar system would get John out of the upper tiers (we're in Pacific Gas & Electric - PG&E - territory where both gas and electric are tiered with a baseline) and down into the baseline but should only produce 70% or so of his electricity. And that adding some insulation might bring that up to 80% production or so. So John called me, saying he was looking for someone he could talk to about adding insulation in the attic. Having some flexibility for rest of the afternoon, we made an appointment to meet at his home this very afternoon.

First, about the house. It was a 1968 ranch style home in a bedroom community out at the western fringe of Santa Rosa. John and Jane, his wife who wasn't there at the moment, had been in the house for 10 years, had replaced all the windows with new double pane vinyls, replaced all the ducts because of rodent damage (and hopefully closed all the rodent holes in the crawlspace), and the house looked sharp inside with newish floors, kitchen, and paint. There was a 12-14 year old natural gas furnace with all ducts in the crawlspace, an outside air conditioner heat pump. A smallish dining room, 10 X 10 or so, was added on to the end of the kitchen, had large french doors west into the back yard, and it was always cold in there. A large, 20 X 20 or so, living room addition was out the west wall into the back yard, possibly on a slab, and IT was always cold, also. One of the original bedrooms tended to be cold and had very little flow out of the supply register.

John and I spent a half hour or so getting acquainted, sitting at his dining room table. He turned out to be a truly interesting man, older, well traveled and thoughtful, and now worked at a nursery. After trading enjoyable and increasingly personal stories for a while, we started discussing his thoughts and questions about what he thought his home might need and why. From there we moved on into more holistic full-house efficiency concepts and I was pleased to see he was open to wider possibilities than just insulation. We discussed air barriers, thermal barriers, crawlspace issues, insulating the roof vs insulating the ceiling, furnaces vs heat pumps, and more. And then we agreed that I would do a full audit of his home.  Running low on time before the next meeting meant that much of my fact finding about John and Jane's home would have to wait til the day of the audit.  I did, though, ask for a years' worth of utility bills.

Now I need to be sure you know a few things.  John already knew about our local SCEIP program and wanted to finance the whole project through them.  SCEIP strongly encourages a full audit prior to applying but at this time doesn't require it.  However, the EUC program does and bases it's rebate on the percentage modeled improvement to the home's energy usage, which requires both a test-in and a test-out.  Second, my audits are not cheap.  I charge $700 for a full audit.  They're pretty comprehensive but I still lose some possible clients because of the price.  I'm not saying that's good or bad, that's just my business model.

Well, I already did a minor faux-pas: when I left, I told him I'd try to move a few things around to get to his audit next week and call him between 6 & 8, and here I was writing this blogpost and missed the time til 8:30, at which time my call to him went unanswered.

Oh well.  Day 1 and I'd already blown it.

Surprising results

Just did an audit on a VERY high end home up on the ridge above San Rafael, above the ferry building.  Built in 1913 for a well heeled ship's Captain.  Wild layout but was ready for a remodel, something the new owners were doing.  A brand new high efficiency furnace system was already installed with all new ducts and they looked *beautiful* from the outside.  Very neat and clean, beautifully finished and taped, we expected very low duct leakage. So we sealed up all the registers we could find and pressurized the duct system.  Surprise!  It was off the charts high.  First thought: perhaps the manometer was hooked up wrong or was on the wrong setting.  Nope.  Then perhaps we missed a register and that was why we couldn't pressurize the system.  After crawling all through the house; attic, upstairs, downstairs, basement, crawlspace, we couldn't find any open registers.

Next: get out the smoke generator so we could blow theatrical smoke in to the duct system and perhaps we could then see where it was blowing out.  Running around the house while the smoke generator was sending smoke in to the duct system, the whole place was slowly getting smoky.  Everywhere.  After working on this simple duct pressure test for 2 hours and going over everything multiple times, we finally had to face the fact that this beautiful duct and furnace system leaked like a SIEVE!  I mean huge leakage.  We had the duct pressure fan up to max and still barely were able to get a number of CFM leakage.  Ready? Over 1100 CFM25.  Perhaps that doesn't mean anything to you but we were expecting around 100 CFM from a new, correctly installed system and we got over 1100.  1100 CFM is another way of saying that the duct leakage was around 50%, meaning half, HALF, of the heat put out by the furnace was lost to the outdoors before it ever got inside.  And in a brand new system, no less.  I was floored.  Part of the report will emphasize that the contractor MUST get the HVAC sub-contractor back out there to do his own test and fix the system.  It won't be easy and there may be some metaphoric blood spilled but the owner has the right to a correctly installed system.

What an example of a beautiful façade hiding a lousy system.  Note to self: put aside your snap assumptions until the data is in with the real story.