Light, Bright and Fun

This week, builder Ryan was busy painting the interior while his crew worked on the siding.  There's just one side of the house to go, and then the exterior will be painted too.  Meanwhile, carpenter Keith was busy off-site building our kitchen and bathroom cabinets.  He delivered most of the base cabinets on Thursday and Friday and will be back on Monday to install them.  Once installed, they will be measured for the fabrication of the quartz counter tops.  We also placed the order for the appliances.  Exciting!  The second glass back door was installed yesterday, and now the main room is extra light and bright.  We went with "chalk white" for the main room and stairwell paint color, and included fun pops of color throughout the house.  Check out the latest pictures!

Everyone asks when we're moving in, and it's looking like mid to late October.  There is a long list of tile, trim, flooring and other finishing work to do, not to mention important things like getting the house hooked up to electricity, gas and water!!!  When city workers insist that you already have a water meter, but clearly do not, all bets are off.  Let's hope we get that little detail worked out soon! 

Paint, Siding, and Doors!

We're very excited to see paint adding color inside, siding going up outside and gorgeous exterior doors being installed!  We're using zero VOC paint and, wow, what a difference that makes for the air quality.  We can take the boys over to see their newly painted room and not worry about them breathing the solvents.  For the siding, we switched from the planned cement board to using oriented strand board (OSB) siding on the recommendation of our builder.  He likes the SmartSide OSB product and thought its strength is better suited to span the distance between the rain screen spacers, which are 24" on center.  With half the house and the whole garage finished, we think the siding looks great and are working on finalizing the paint colors for the exterior.  As for the doors, we have to say that they were worth the wait.  They turned out just as we had hoped.  The front door was installed the day my uncle Ron and aunt Jeannette came to visit from Marshall, MN.  After giving them the grand tour, my uncle said this is the way all houses should be built.  That was of course after he did his share of teasing the crew that I was timing them during their lunch break.  Uncles.   :-)

Living Roof

A later addition to the scope of our home project was the need to build a garage.  We had originally planned to delay garage construction, but part of the building permit process is a design point system that totals 15.  You get zero points for energy efficiency and 5 points for a garage, so what do you know- a garage is built.

Beyond a 2-car-garage with extra storage space, having a living roof on top was the only requirement we had.  The main reasons were to minimize storm-water runoff, do our part to improve urban air quality with more garden space, and to have a beautiful garden view from our second floor.  We have yet to decide what will be growing on top, but have been inspired by some books and pictures.  We look forward to working on this big gardening project next spring. 

Inspirational pictures to help with the design..

A picture is worth...

The blog has been secondary to summer outdoor activities as of late, but we took the time to document via pictures a few things to share regarding progress:

With all the insulation inside and out, the house is starting to look like a traditional build, but on the inside it sounds anything but traditional.  With the windows closed and all the insulation, you can't hear anything at all.  The pictures below show insulation, webbing, Bildrite, Tyvek, and finally the Fir framing.  Next up on the exterior will be cement board siding and paint!

The window frames received a final round of insulation, since the window/house interface is the weakest part of the window.  To solve that, 4-inch rigid foam insulation was installed around the window and a Tyvek wrap around the bottom.  Once the siding is installed, an aluminum window sill will finish everything off.

Finally, we finish with pictures of the sheetrock going up inside the house making the space well defined and another step near the finish.

Layers and layers

A major portion of the exterior house walls was added this past week with the arrival of 14,000 pounds of dense pack cellulose insulation, a product of up-cycled newspaper.  The new backyard resembled a very tall hay bale maze, and the kids were happy to run and play between the stacks. 

The walls of the house were prepped with webbing to allow for the insulation to be blown into the exterior wall cavity, constructed from 12 inch I-joists.  This week, the insulation is being blown into the interior wall cavity as well, resulting in an R value of at least 48.  The attic will have 24 inches of insulation, providing an R value of at least 70.

Once the insulation is completed, the next level of wall assembly will be added.  Here is the buildup:

photo 3 (3).JPG

1.  Fiberboard sheathing (Bildrite - breathable, insulating, environmentally friendly)

2. Vapor open wind barrier (Tyvek)

3.  Fir framing

4. Scheduled siding (cement board)

Our drywall delivery was also pretty exciting; the driver invited our boys to sit behind the wheel of the huge truck and even blast the horn.  We watched as the driver used his remote control boom arm to bring the drywall from the truck directly to the front door.  For the second floor, they cut a hole in the sheathing and slid the 12-foot-long sheets inside, and then sealed the house right back up.  This had to be done before the insulation was added.  It pays to plan ahead!

A touch of whimsy

This week, the crew built our front porch roof, getting the exterior one step closer to its final form.  When the boom truck arrived to deliver the porch beams on Monday, the driver wasn’t sure where he should put the 26 foot solid cedar beam.  He selected the open backyard and unloaded the beam before we had the chance to tell him it belonged in the front.  He wasn’t sure he would be able to get the forks under it to lift it back onto the truck.  By good fortune, the beam was slightly propped up on a yellow soccer ball that the kids had left in the yard.  This is how the construction of our whimsical front porch began, very fitting!  With the beam successfully transferred to the front yard, the crew went to work the next day.  We put together another time-lapse video to document the process.  Ryan said that at least 6 passersby recommended that he check his level.  Hilarious to think he could possibly be unaware that he was installing it at an angle.  When we first saw the architect’s design, we were pleasantly surprised with the angled porch roof feature.  Tim said it was what one might call whimsical, and we were sold.  It fits our fun-loving family perfectly.  It also suits our eclectic NE neighborhood with homes of all styles and vintage.  The transitional look will become more evident once the traditional bead-board ceiling is installed and stained along with the cedar beams, juxtaposed with the more modern standing seam metal porch roof.

We can also report that the electrical, plumbing and ventilation inspections have been completed, and once the framing inspection is also done, the crew will spend a week blowing the dense pack cellulose into the 18 inch thick walls- a total of 14,000 pounds of insulation!

High Performance? Check!

A high performance house design requires a high quality build.  We met and exceeded the goal for the mid-build blower door performance check with a measured whole house air leakage of 0.42 ACH50 (.42 whole house air changes per hour at 50 pascals pressure).  To meet the Passive House standard, we needed to be at 0.6 ACH50, but that wasn't going to satisfy our highly motivated builder!

Builder Ryan says...   "We started at .64 (244cfm) and began fogging and looking for the "big leaks"... after a couple hours of hunting and sealing leaks we managed to reduce the number to 210 cfm. We then looked closer at the basement thinking that the windows may hold some significant potential improvements only to find that the sump basket and the floor drain were leaking drastically compared to anything we found thus far. Ran the test again and this is what we found! .42 ACH ! Success! According to the PHPP output from Tim Delhey Eian at TE Studio, Ltd., this signifies a 10% reduction in the already 90% reduction in heating and cooling load for this house as compared to building code standards."

To offer some additional perspective on the air-tightness results, we have included the summary table below.  Do you know how your house performs?  We had the blower door test run on our current century-old home, and the number was 7.2 ACH50, that's 7 whole house air changes per hour at 50 Pa, otherwise known as very leaky and drafty.  This is even after considerable effort on our part to mitigate leaks and improve energy efficiency over the past 12 years we've lived here.  The drastic difference in uncontrolled air diffusion is a big reason our projected yearly energy bill for the new house is over half what we currently pay, despite the square footage more than doubling. 

Since the successful blower door test was performed on July 3rd, coincidentally the shared birthday of Julie (homeowner) and Tim (architect), we celebrated with breakfast pastries from Aki's Backstube, the new German-style bakery in NE Minneapolis, brought to us by the Central Avenue revitalization efforts of the Northeast Investment Cooperation.   These are just a couple of reasons we love Nordeast!

Air in, air out... yet airtight!

The week before the blower door test (post soon to come on that), the final component of the HVAC system was added to the nest.  The Zehnder ComfoAir 350 air exchanger, continuously provides fresh air and removes stale air all while recovering 90% of the heat. 

The system takes fresh air from the outside, filters it, and heats or cools it using the temperature of the indoor stale air being ventilated out.  Flexible and smooth HDPE plastic ventilation pipes are fitted within walls and floor joists and connect the air exchanger to air diffusers in the ceilings.  The conduits can be easily cleaned if needed since there are no junctions, angles or cross-sectional changes.

From the air distribution box, a ventilation conduit leads to every room in the house.  Some rooms get 2 or 3 conduits depending on the volume of the room and ventilation needs.  The whole system is balanced for equal air flow in and out.  The fresh air flows into the bedrooms and living areas, while the stale air is removed from the kitchen and bathrooms.   The kitchen has 3 conduits, which should prevent cooking smells from lingering or migrating upstairs.  The system virtually makes no noise, with silencers fitted to the air diffusers.  This will certainly be a change for us, being used to our very loud bath fan and air moving through our old metal grates as the H/AC system kicks on and off.

 As it replaces the stale humid air at maximum capacity of 215 cubic feet per minute, it provides another key service to the tight house which is preventing mold.  The design of the house follows hygrothermal modeling which pertains to the movement of heat and moisture through the home.  The computer based modeling offers highly accurate predictions of hygrothermal performance for preventing early degradation.


To service the system we simply will need to replace the filters when needed.  The heat exchanger itself can be taken out and washed with water every 4 years.  With our 3 kids each about 4 years apart, we can someday use milestones such as high school and college graduations to remind us.

Cool breeze on an open porch

We have had a few days with beautiful summer weather, and thought it would be fitting to highlight the porch slab and stairs being poured.  What a sight!!  We are very happy with how this turned out, as we diverged from plain cement and added a darker "limestone" tint to the mix.  It darkens even more when it gets wet, and once it is done curing we will seal the sidewalk and steps making that rich dark color final.  We anticipate the cedar posts and 26 foot cedar roof beam to be delivered Monday, which will allow the porch roof to be built.  Stone work around the porch base will come in at a later time.  We might just start sitting out there on weekends, just because we love it so much!

Behind the Walls

This week's update has a number of items to cover.  With the windows installed we now wait for the doors to be delivered (see "The making of the house doors" post).  Once the two back doors are installed we can run the blower door test to check for air tightness.  In the meantime, work has been focused on the inside with plumbing and electrical. 

The plumbing work is nearly complete with all the drains and vents installed along with the water supply lines.  The hot and cold water lines are insulated the entire run.  Here are a few pics of the wall with the plumbing and one of three Geberit toilet carriers with
the tank concealed in the wall. The toilets will be wall-hung Aquia units from TOTO.  We picked this model for it's Dual-flush system, and low water consumption (1.6GPF/6.0LPF & 0.9GPF/3.0LPF)

All of the electrical boxes for switches and outlets have been placed, along with the recessed LED fixtures and mounts for the other light fixtures.  RJ Stegora made sure everything was in the correct location before letting the electricians begin the wiring. 

The two window wells were installed and back-filling was done with top soil.  Some additional grading needs to be completed when the sun is shining.  The garage floor was opportunistically poured during a short break in the torrential downpours this week.  RJ Stegora accommodated a special request we had for the west and south side of the floor. Check out the pictures and see if you can guess.  Give up?  In the slab we have a total of 4 low-profile bike locks for the kids.  Simply fabricated with a plumbing elbow immersed in concrete, you just run the bike lock through it.   We did add one for locking a lawnmower or snow blower.  Pretty slick!

Die Fenster (The windows)...Wow!

From Hamburg, Germany to NE Minneapolis, our windows arrived safe and sound.  These beautiful windows come painted and stained, and we were anxious to see the "curry yellow" we selected for the exterior and the dark brown wood stain for the interior. The windows are gorgeous!  We love the pop of color this gives the outside of our house.  

These versatile windows open to the inside for super easy cleaning and to let in a strong cool breeze, or the top of the window can be tilted in for a gentle influx of fresh air.  As far as energy performance goes, they have an insulation R-value of 8, and a solar heat gain coefficient of 50% with glazed triple panes filled with Argon. The installation involves tape, spray foam, and more rigid foam insulation to achieve the air-tightness of the home.  The installation went smoothly, and they were all in place in one day.  RJ Stegora crew had to install a couple at the end of the delivery date to help us sleep knowing at least two were up.  All in all, the most challenging part was unloading and carrying the windows into the house.  It took some major teamwork to tackle these behemoths; the larger ones were about 300 pounds each!

The windows provide optimum performance for Zone 6/7 which we have here in Minnesota.  Some additional benefits they provide:

  • Inner layer implemented as a statically bearing structure
  • Short renovation times thanks to removable outer layer
  • Interior wood types: fir, spruce, larch, oak
  • Removable aluminum outer layer
  • Slender frame, elegant design
  • Custom color schemes for interior and exterior
  • Special functions: sound insulation, sun protection and intrusion prevention
  • Custom detailed planning
  • Up to UW 0.70 W/m²K (Ug 0.5 W/m²K)
  • Certified connection free of thermal bridges (PHI Darmstadt)
  • For renovating also possible without frame insulation (UW value determined according to respective installation situation)

I found this video to be helpful visually (no audio), I plan on posting a video of my own when I have time demonstrating the functionality.

When the sun doesn't cut it... the heat pump will

The "Passive house" concept relies on the sun as a heat source, as well as internal heat sources such as people and appliances.  The typical Minnesota home needs a furnace with a heating capacity of 80,000 Btu/h.  In contrast, our house could use one with a heating capacity of only  14,000 Btu/h.  The system that was installed is a Fujitsu variable speed multi-split heat pump.  It has almost twice the necessary heating capacity, but was the lowest available.  This system also provides air conditioning with a cooling capacity of 22,000 (Btu/h).  The split system heat pump means that the compressor and condensing coil are outdoors and the evaporator coil and blower are indoors.  Two indoor units were installed, concealed within the ceilings of the first and second floors.  These systems are often ductless, but our architect designed a ducted system to insure each room would be comfortable.  To heat the basement, two small electric baseboard heaters under the windows will suffice, and no active cooling will be needed down there.

Progress was also made on our alternative heating system- the gas fireplace.  The framing was completed and the unit was set in place.  Marketed as the "world's most efficient fireplace system", the vented Mantis fireplace exceeds 90% efficiency and humidifies as it heats.  We anticipate enjoying the ambiance and utilizing the thermostat-controlled fireplace as the main source of heat on most winter days.  With a heat output of 25,200 Btu/h, it alone exceeds the needs of the home.  In reality, the heat pump was installed to fulfill the code requirement, but the air conditioning it provides sure will be nice. 

Our fresh air ventilation system with efficient heat recovery is yet to be installed, and we'll describe that when the time comes.