Flatrock Passive House: A Passive House in Newfoundland

In the previous post I presented the results from two blower door tests.  The blower door results from the garage testing can be used to determing the heat load required by the building.  We can think of the heat loss as a sum of two components:  Heat lost through conduction and heat lost due to infiltration.  This is a highly simplified method and only partially describes the physical behaviour of heat loss.  For example it neglects to account for thermal mass effects, treats conduction as a one dimensional phenomena, ignores convection currents, ignores the thickness of the walls, etc.  However, this simplified method typically overestimates the size of the required heat source so its good enough for this purpose. Calculating yearly demand is a matter of breaking the structure up into individual components.  First I calculated the area of each component using my construction drawings.  The product of area, R-value, and 24 hours/day gives the heat lost per degree day.  The website w

I probably mentioned before that I would cringe every time we had to drill out through the air barrier.  Every time I drill through it I would wonder if I could get back to the level of air tightness I achieved on the initial blower door test.  With almost 21 penetrations for electrical, plumbing, mechanicals including the HRV and wood stove, it seemed like it would be impossible to achieve the level of air tightness required to get the efficiency I wanted.  However, with good air sealing details, the task wasn't as hard as I originally thought it would be.  Custom gaskets, lots of acoustical sealant,  and 3M tape just crush any chances of air getting in! Previously installed conduits where wires were routed were filled with spray foam.  Plumbing sewer pipes that were vented to the outside were tape sealed.  The air vent for the wood stove and the chimney thimble were sealed with plastic and tape. The biggest problem area was routing wires through to the garage.  Installing con

 We had a plan of attack from the beginning.  That plan involved erecting all exterior service walls first and then framing the interior walls later.  The plans call for 24" o.c. studs for the service wall.  That's about the only details we had to go by except how to terminate around windows and doors.  The framers worked pretty quickly at framing the interior.  The service walls were almost completed after two days of work.  To strengthen the interior petitions and service walls, we install staggered blocking at half height help prevent the wall studs from bowing, warping and twisting (Picture 1).  Now its starting to look like a house!  Since we would be installing drywall returns around all windows I opted for adding the 1/2" drywall return slot to the window frames at the time they were made.  To make the lives of the drywall installers easier, the rough stud openings had to align with the drywall returns so shims wouldn't have to be used (Picture 2).  We framed

Attics are cold in the winter and warm in the summer.  Since they are vented through the soffit they are also drafty spaces.    The attic could become an energy sink without lots of insulation and good air sealing details.  We are at a point in construction where we have to start penetrating out though the air barrier and into the attic.  I find this scary but its another reminder that we are progressing nicely. With our blower door test measuring air tightness of the air barrier at 0.45 ACH50, I cringe every time somebody suggests that we have to drill a hole in it!  This being said, I knew it would be inevitable.  So we move forward with plumbing and wiring details.  Although we placed all the washrooms on one side of the house, it was pretty much impossible to tie everything into one main vent stack.   There service cavity on the ceiling is 2x4 strapping on face so there just isn't enough room to route each vent to a common place and terminate them together before penetrating

It has been some time since my last post.  Things have been so busy that I just haven't had time to document things as much as what I would have liked.  This being said, I figured I would provide a quick update on the exterior progress....It is now complete!  Keocan General Contracting completed the siding job.  It is well done and the house looks great! Earlier in the blog series I pointed out that the clapboard and trim were obtained from Cottle's lumber and wood products.  After working with it myself, I can say that it is a great local product.  Several cladding options including pre-finished siding could have been an option but at up to $1.89/lf those options were expensive.  If you're willing to finish the siding yourself, wood cladding can be an option.  Installation will be more expensive than vinyl but that cost can be somewhat offset by the cost of prepping the siding yourself.  We used Benjamin Moore Arborcoat exterior water based stain.  The color swatches for

Now that I have had time to assess what was left by the first siding contractor, I have found many issues.  Some had to be fixed, others will never be noticed and none of the issues will be detrimental to the building, so I opted to save materials rather than waste them.  The project basically halted for about 6 weeks with the exception of a few interior things. Things are moving quickly now that Keocan General Contracting Inc. are on site.  They have completed about 75% of the siding and are now working on completing the remainder of the soffit and fascia amongst other things.    This is the good news.  The bad news can be seen in Photo 1-1.  The previous siding company installed the siding courses at odd intervals.  I specified 4 1/2" but they are all over the place.  This being said the install looked fine since 1/8" here an there isn't really noticible.  However, I knew moving forward that carrying these errors around the whole building would be impossible.  Pat and

The last big change inside the garage was when I added the attic baffles.  That was in august.  Little has changed since.  That changed today!  With interior framing on the house underway, I really wanted to make some headway with attic insulation in the garage so I could continue some framing details in parallel with the framers.   The insulation needed to be installed before adding the interior OSB to the underside of the trusses and tying the internal air barrier to the external one. I mentioned in a previous post that my garage will be a workshop.  I want it to be fairly energy efficient so I opted to add 3" of exterior foam on the outside of the building to prevent thermal bridging.  I also want it to be as air tight as possible...which is probably not that possible with a leaky garage door but we'll see.  A typical wall section is composed of  3" EPS, OSB, 2x6 stud wall, then drywall.  The exterior OSB joins were caulked with acoustical sealant and further sealed

Things have been slooooowwww.... For reasons that I may decide to document at a later date, my siding contractor is not on site anymore and will not be...ever.  Lets just leave it at that for now. The company that I hired for framing my house (Keocan General Contracting, Inc.) will be taking over the cladding installation.   In fact, the last photo of the house did show the guys from Keocan onsite and the progress they had made in only two days (Photo 1-1). They did get started but ran into some things with another job that required putting mine on hold.  This being said, I am grateful to Patrick (Keogh) and his guys for taking on the job on such short notice.  My experience is that he is trustworthy and will get the job done to my specifications. To keep the build moving along we have been picking away at various things so they would be done once they get on site to finalize this stage of the build.  They will complete the cladding installation and then the interior framing.  To ge

Dealing with penetrations in the air barrier has definitely been a source of stress during this project.  Although my plans contain the penetration details, implementation of those details is pretty much left to me; unless I decide that I need help and in which case I would call Passive Design Solutions.  Some penetrations through the air barrier needed careful thought and planning before jumping in otherwise you could risk the integrity of the air barrier and fool up the insulation in the wall cavity all in one shot.  There are 5 wiring penetrations to the outside:  3 receptacles and 2 lights (well there is actually 3 light circuits but two which were more worrisome than others.) Mounting the light/receptacle blocks to the exterior of the building could have been a mess if there was no foresight.  It is hard to attach a trim block to a foam wall.  The only solution was blocking attached to the studs directly behind the foam in the wall before the cavities were insulated.  I used 2x6