Taylorville High School / Pretty Good House Status Update 8: HVAC Mechanicals and Drywall SpotlightFeb 28, 2025
We’re getting a good winter in central Illinois, and despite stretches of sub-zero and single-digit weather, Matt’s students continue working hard. The house easily stays above freezing despite no insulation added above the ceiling yet. Matt plans to have Timber HP wood fiber insulation blown in once plumbing vents, solar PV electrical, and other miscellaneous attic area activities.
The reason the THS PGH net zero home is naturally protected against indoor freezing is the home’s “ground coupling”. Matt superinsulated the foundation walls, but not the ground underneath the crawl space. Even in severe weather with no house power for extended periods, indoor temperatures will never drop to freezing and plumbing will never freeze. This is especially important for vacation homes and cabins in remote areas.
Ground is an exceptional thermal mass that “pins” a home’s interior to near ground temperature during power failures. Adding high R-value insulation underneath a slab isolates the home’s interior from ground temperature, reducing both freeze protection and thermal “massiveness”. Ben and Ty wrote articles for the ASHRAE Journal on ground and foundation wall insulation and thermal mass. Equinox House, with no underslab insulation, has a “barefoot comfortable” floor all year round.
A series of photos from the past month describe Taylorville students' activities. Follow Matt Blomquist’s Instagram (build_learn_teach) posts to see the most recent THS build program activities. If you attended the IBS this year, hopefully you were able to meet Matt at one of the workshops he participated in. He’s a master builder and educator, and a wealth of information!
Ty delivered a CERV2 donated by Build Equinox to the THS PGH net zero home project. A lot is left to do, but everything is coming together nicely with Matt Blomquist’s exceptional planning.Students reconfigure the Aprilaire dehumidifier unit for a right angle (vertical outlet, horizontal inlet) air flow. They also moved the control panel from a top unit orientation to a back panel orientation that will be easier to view and access.Fits like a glove! The two holes on the right wall are for fresh air inlet (higher hole) and exhaust air outlet (lower hole). 8” diameter inlet and outlet vent hoods with ¼” screens will be mounted outside. Supply air exiting the CERV2 goes vertically upward to an 8” tee with air split to the ducted minisplit on top and the ducted dehumidifier on the shelf. A spring loaded damper on the dehumidifier outlet is operated by CERV2 which controls operation of both minisplit heat pump and dehumidifier. The vent on the upper left wall is a transfer vent from the laundry room, pulling air into the mechanical room to keep the AO Smith heat pump water heater operating efficiently. The HPWH will be mounted on the left of the mechanical room doorway. Return air pulled through the adjacent laundry room allows it to be used as a “drying closet” for those who prefer hanging some clothes for final drying. This compact mechanical room allows plumbers and HVAC installers in the future to conveniently work on equipment.Students watch one of their buddies applying compound. There’s no shortage of “helpful” comments from the crowd. Many students have known each other since elementary school. Anyone visiting the project would not be able to tell drywall was installed by a group of rookies. Matt commented that this group has a lot of skilled people who pick things up fast and take pride in their work.Every nook and cranny finished nicely!Matt stresses the importance of clean up. Dirty tools take extra time to fix the next day.Ty was headed back to Build Equinox from the THS project when his buddies, Sam and Gary notified him their fresh hopped brew was ready for tapping…so, Ty didn’t make it back to work.Sam and Garys’ fresh hopped brew used hops from Build Equinox wall-of-hops. The brew needed a few months to mature. It was hard waiting, but like many things, worth the wait!Hops grown on the south facade of Build Equinox laboratory adjacent to our 3 acre “Solstice Prairie” were used in Sam and Garys’ tasty brew. “Sunflower” (3.2kW two-axis solar tracker) and “Sundial” (5.5kW solar PV sculpture) are enjoying a sunny day. Hops are a great summer shade plant for buildings, keeping even light color facades like our building 20 to 40F cooler than unshaded siding, lowering summer AC loads. Hops die back to the roots during winter, uncovering the façade for a beneficial solar contribution.
Ready to get started? Fear not, we're here to help! Fill out the contact form below, and we'll guide you through the process.
edit_note
Step 1
Fill out the contact form.
east
mail
Step 2
We'll reach out to get more information about your project and answer questions.
east
partner_exchange
Step 3
We work together to help finalize the design and options.
east
local_shipping
Step 4
Get your CERV and start breathing fresh, healthy air!
infoWe work with a variety of customers: whether you're looking for an installer recommendation, have an installer of your own, or even want to do everything yourself...we've got you covered!
