BALANCED VENTILATION

 

 

 

Our fresh air ventilation  units arrived last week from 475 High Performance Supply.  We are using the Lunos e2 units for fresh air and the Lunos EGO unit for bathroom exhaust.  These units provide a constant supply of balance fresh air, even when exhausting our bathroom.  More information and installation photos are on the way.  Stay tuned!

UTILITY CONNECTIONS

We began setting up the utility connections last week for power and water.  The existing lines between the shed and main house were re-routed to the Studio's Utility Room.  You can tell by the number of pipes we were trying to prepare for every conceivable situation.

 

We have a power line into the Studio and a power line out to the future garage.  Three water lines into the Studio will accommodate the existing well and future city water.  There's one extra line for a hot tub (fingers crossed??!!) or anything else we might think of in the future.

 

With all that in place, we can set the HVAC pad and disconnect.  We don't want the refrigerant line visible on the side of the house so a small sleeve will be placed below the disconnect.  If all goes well this will be hidden behind the outdoor unit.  Josh and his team at Air Handlers Mechanical Service will install the unit next week.  For this project we are using the Mitsubishi 'Mr. Slim'  high efficiency mini split heat pump. 

 

EXTERIOR SIDING

 

 

Flashing is one of the most rewarding things to do when building a house, especially when it's your own.  A little bit of patience, some extra break metal, and some attention to detail will go a long way.  Architects spend a lot of time drawing details but I've found that executing them can be just as fun. 

 

 

Window box flashing on the south side of the house.

 

 

 

A full length metal break is worth it's weight in gold.

 

All our windows have been 'over-insulated'. Much of the heat loss around fenestrations occurs at the interface between the window unit and the rough opening.  We've installed 1" rigid foam in this area to reduce the thermal bridging around the window's perimeter.

 

At the sill we have to be careful not cover up the weep holes.  Here we used spray foam under the sill board.

 

The siding is going in with the exterior shading device box.  After all the siding and trim is installed, Douglas Fir wood screens will be mounted on sliding tracks above the windows.

 

 

 

PRELIMINARY BLOWER DOOR TEST

Bill Nickerson is our PHIUS + rater.  We performed a preliminary blower door test before we installed the exterior insulation to make sure we were on target. 

 For our preliminary test we achieved about 0.7ACH at 50 pascals.  We have a small space and Bill had to break out the 'D' ring to get the right air flow.  For the final test we need to achieve 0.6 - we are almost there! 

EXTERIOR RIGID INSULATION

2" Polyiso rigid board insulation

 

 

Each window gets a 'window buck' or 4" wood frame around it's perimeter to enclose the insulation.  We also pulled up the vapor barrier from the foundation in order to have a continuous barrier from the underside of the slab up to the roof.

 

As with all the insulation, a tight installation and overlapping seams is a must!

 

We had to add a small strip here but will overlap these seams on the final layer.

 

We liked the grey color so much we are thinking about repainting the entire house......yikes!

 

Once the insulation was installed we added the rain screen battens and taped all the frames.  This is where we lap in the first layer of flexible flashing.

ROOFING INSTALL

 

Once the roof material arrived we didn't waste any time getting in on the building.  We chose the same metal roofing used on the existing house. These are exposed fastener, gavalume coated steel roof panels.  If all goes right it should last for a long, long time.

THE ROOF ARRIVES!

INSTALLING THE WINDOWS FROM INTUS

Our dog Ulu gives new meaning to 'strike a pose'!

We started preparing all the openings for the window installation. 

 

 

Mac takes a moment to inspect the opening prep.  On the inside of the frame we used an expanding foam tape, caulk, and setting blocks to seal the perimeter of the frame.  It was a warm day so we used a trick from the guys at Hammer and Hand  Construction Co. and kept the foam in a cooler to slow down the expansion process.  This gave us a little more time to set the windows before tape expanded.

 

 

On the smaller windows we did not use the flexible flashing on this layer.  We will save this for the outermost layer. In the corners we added a small bead of caulking to make sure we closed all the gaps.

 

On the larger openings with multiple units we added the flashing as an added precaution.  We weren't sure this was necessary but we decided to install it for peace of mind.  Notice that we did not adhere the lower flashing to the exterior wall.  This will get lapped into the next layer when the insulation is installed.



 

 



GOLD!

Our primary weather barrier layer is a liquid applied coating from Sto Corp. called Sto Gold.  Once the exterior sheathing is complete we will apply multiple coats over the entire envelope.

 

 

 

The first coat is covers all seams, corners, and openings.  After that you apply multiple coats until you reach the desired thickness. 

 

 

Despite all the weather setbacks we had in the fall, this weekend we struck gold in the middle of the winter.  We topped out at almost 80 degrees this afternoon and will not fall below 50 for the next couple of days.

 

 

 

Next step will be the windows from Intus.

 

THE ROOF

 

We elevated the overhang outriggers so we could place some of the rigid insulation below the members and reduce the thermal bridging at the roof.  Our design calls for 6" of rigid polyiso insulation.

 

One more layer and we are ready for the top layer of sheathing.  When we are finished it will function like a SIPS panel on top of the studio.

 

 

We were able to get the final layer of sheathing and ice and water shield installed before the snow set in.  It will be a couple of weeks before the metal roof arrives so we covered everything with 10 mil poly for protection.

 

 

 

 

 

FRAMING

 

We used a neoprene gasket from Conservation Technology under the sill plate. This product was recommended based on past performance on other Passive House projects.  The under-sill area can be difficult to seal even when you don't have to pass a blower door test.

 

 

Glen came back to help us frame.  He wasn't surprised at any of the framing details although they don't call it 'Advanced Framing' anymore.  Builders are more than happy to reduce the number of boards they buy for a job.  Less lumber means less nails means less labor, time, etc.  I've always enjoyed watching him dissect a set of drawings.  He provides great feedback on the things I've drawn and how they are used to put the house together.

 

 

Oliver has grown up a little and this will be his first time as cut man.  Let's see if he can keep up!

 

 

The first wall goes up!

 

 

The boys helping Glen set the header over the bathroom window.

 

 

 

 

UNDERSLAB

 

 

The great thing about having kids is that they are always younger than you.  When we started renovating this house the boys were 4 and 6 years old.  No matter what we did they were chomping at the bit to get in there and help out.

 

 

If you needed  a hand holding something - they were on it.  Especially if it meant climbing on something dangerous like a scaffold, walk plank, or ladder.

 

 

If we didn't have an extra ladder ....they'd make one.  As long as they could help out.

 

Fast forward 10 years......

 

 

This is big ass pile of fill dirt #2.  It needs to go into the foundation before it rains tonight and David's Bobcat is broken.  Suddenly our two little helpers have lost interest.  (Remember, Bobcats are a lot more fun to drive than a hand shovel.  "What do you mean the Bobcat's broken........... uuhhhh, I have a lot of homework tonight, sorry."

Somehow we coaxed them into helping out, paid off a couple of their friends and had the foundation filled in about 6 hours.  Let's just say we all moved pretty slow the next day...even the teenagers.

 

 

The insulation extended across the top of the footing and up the inside of the foundation wall.  It was braced in place as we backfilled the dirt.

 

 

 

4 inches of  XPS insulation was placed on top of the compacted fill with staggered seams.  The vapor barrier, reinforcing, and any remaining under slab items followed.

 

 

This is where is all starts.  Sealing up all penetrations under the slab.

 

 

We have extra capacity in our solar thermal system and placed a hot water loop in the bathroom floor.  Most Passive House projects don't need the extra heat but we are addicted to warm toes on the floor in winter. 

 

 

 We did not want the large circles left by the whirly birds on our exposed slab so we requested a smooth hand troweled finish.