Image Credit: All photos: Carl Seville This 190 cfm fan will be used to transfer conditioned air from the hallway minisplit to the two front bedrooms. The installers had to do some careful work to get the minisplit refrigerant lines through the walls to the exterior. The ERV will provide outside air. It will also help circulate conditioned air from the first floor minisplit to the back side of the house. The ventilation system was installed with hard duct except for where the duts tie into the top-mounted intake and exhaust ports. The ERV intake air flow measured out at a rate exceeding the minimum required for ASHRAE 62.2, LEED for Homes, and Energy Star. Happy to have that item checked off. The site-built hot water manifold will get hot water to all the fixtures quickly with minimal waste. The Zip sheathing is taped and windows are installed. HVAC refrigerant lines are run through PVC pipe angled down through the sheathing. The PVC conduits are taped to the Zip sheathing for a solid weather barrier, and will be sealed with foam before insulation for a compete air barrier.
Carl Seville and his wife are building themselves a new home in Decatur, Georgia. The first blog in this series was titled The Third Time’s the Charm. Links to all of the blogs in this series can be found in the “Related Articles” sidebar below.
The process of building a house reminds me every day how happy I am to be out of the construction business. I realize now that I wasn’t cut out for the daily stress of the construction industry — in part, I believe, because I care too much.
I wake up in the middle of the night obsessing about details and methods. I think and rethink minor decisions. And sometimes, I am too nice and forgiving of inferior workmanship.
I take responsibility for some of the problems we are having, mostly due to not making decisions early enough, or not thinking through all the details thoroughly. The biggest problems, however, have come from trade contractors and vendors not meeting my expectations. Material orders are incomplete, late, or just wrong. Carpenters seem uninterested in listening to what I want, instead simply doing what they always do: framing things fast and loose, and in some cases, just framing things wrong, including out of plumb and level, with doors and windows incorrectly sized or located.
Recent weeks have been spent coaxing carpenters back to the job to complete their work and correct mistakes — and thankfully, we are closing in on completion of that phase of the work.
Enough complaining — on to our progress
Now that the house is dried in, work on mechanical systems is underway. Plumbing rough-in is complete, and thankfully worked out mostly as planned.
I decided to install a home-run hot water supply system to minimize the wait for hot water and to reduce the amount of water wasted in the process. The plumbers installed a site-built hot water manifold with ½-inch insulated lines run to each fixture.
We were able to keep all the hot water runs to less than 30 feet through a combination of a centrally located water heater and careful placement of the PEX pipes. By minimizing run lengths as well as elbows in each line, I expect that we will have hot water to each fixture within 20 seconds, wasting less than a half gallon of water in the process. While this not optimum, and my friend Gary Klein would probably be very upset with me (since he likes to waste no more than a half a cup of water in his designs), I am happy with the results.
Gary suggested that I install an insulated circulation loop that ran right next to each fixture, supplied by a demand pump. I did consider this method. I have both used and recommended demand pumps over the years, but (as with many things in this house) I wanted to try something different. We will see how it works once the project is complete, but I have confidence we will be happy with the hot water system.
Ductless minisplits, exhaust fans, and an ERV
HVAC rough-in work is complete. One unexpected problem was the challenge of installing the refrigerant lines for the Mitsubishi ductless minisplits. Not wanting to have them snaking around the outside of the house, the installers drilled out studs to run the lines through the walls (our only option since there is no crawl space). Unfortunately, in the process of pulling the line sets through the walls, most of the insulation was torn off, and although it has been corrected, a sleeve under the slab for these lines would probably have simplified the installation.
I worked closely with the installers on the exhaust fan ducting, and they did an excellent job installing short runs of hard pipe for the Panasonic exhaust fans — something I rarely see in most homes I inspect and certify.
The Broan ERV is installed, and since it has a standard 110-volt plug, I was able to test the air flow rate before completion. I am happy to say that it exceeds the required minimum for ASHRAE 62.2, and while I probably won’t use it most of the time, the ERV helps the house comply with LEED and Energy Star requirements, as well as my local green building ordinance requirements.
Electrical work will begin shortly. Without adequate solar exposure, I am not able to install PV panels, so the installation is a pretty standard affair.
The house will be illuminated with mostly surface-mounted fixtures and a few recessed wall washers. I recently ran across a surface-mounted LED that has the look of a recessed light. The Lightolier SlimSurface LED fits in a standard depth 4-inch box with the look of a recessed downlight. The 2700 K temperature combined with a 90 CRI (Color Rendition Index) give it a light quality very close to incandescent at a very reasonable price. (For more information on the SlimSurface LED fixture, see these two GBA articles: Rethinking Recessed Lighting and Canned Lighting Conundrum.)
We are currently selecting pendants and sconces, most of which will likely be standard Edison-base fixtures into which we will install LED lamps. The selection of integrated LED fixtures is still limited, and those that are available are quite costly, so using standard fixtures is an easy decision.
Coming up next
Siding and exterior trim will commence shortly after the electrical work is complete. No exterior finishes will be installed until all of the mechanical penetrations — including wires, pipes, and ducts — are installed, weather-sealed, and air-sealed.
Following that, we will be installing a HomeSlicker vented rainscreen on all the walls, covered by Boral TruExterior siding and trim. The TruExterior is a good-looking product comprised of coal ash and recycled polymers. I haven’t yet used it but look forward to trying it out. It is similar in finish to mineral-fiber products; however, it is available in a much wider variety of sizes, including a 1×6 resawn siding, tongue-and-groove beadboard, as well as 1x, 5/4, and 2x dimensions up to 12 inches wide. With the exception of the lookouts at the soffits, we don’t expect to use any wood on the exterior of the house.
On the interior, the next steps are to complete the installation of the Term vapor and termite barrier on the slab, install the plywood subfloor, apply borate treatment to the framing, and install the air sealing details and insulation.
We are currently planning to do a blower-door test on the house after the windows and doors are air sealed to confirm the effectiveness of the Zip sheathing air seal. Following that, the Owens Corning Energy Complete sealant and blown-in fiberglass insulation will be installed in preparation for drywall.
It’s a long, slow process, much of the time more stressful than satisfying, but I am looking forward to the finished product.