OK, ‘Tyvek’ isn’t a verb.  But, then again, neither is ‘Google’.  But everyone ‘Googles’ people, materials, terms, etc.  We ‘Tyveked’ our roof today.

Dave Edwards’ two-person team from Earth Bound Homes worked all day putting building wrap (Tyvek) over the flat and gable roofs.  The Tyvek needs to be in place before Akeena Solar puts in the solar mounts and conduit on the flat roof.  The installation team from Akeena Solar will be on site on Friday morning (08/27/10).

During the day, Bryan made several trips to pick up materials so the team could continue working.  These materials included 5 ft wide Tyvek, 9 ft wide Tyvek, and Stinger staples.  We don’t want the crew working to pause for a moment because they don’t have materials.  As well, we don’t want to have more materials than are required to complete our project (controlling and limiting our construction waste).

Also, White Cap delivered our expanding foam and more Grace Viecore Plus so we can have a robust air and water seal between the flat and gable roofs.

Finalizing the Plans for Our Solar Photovoltaic Panels

Akeena made the final changes to the plans for our solar mounting system.  Sheet PV-1 shows the layout of the 6 arrays of 8 solar panels on the flat and gable roofs.  Sheet PV-2 shows the details of how the arrays will be attached to the roof. 

We worked with Akeena (Duk Lee in particular) to design the mounting system to optimize the production of electricity and to reduce the number of cables and penetrations of the thermal envelope. The benefit of designing the system in advance is that the system should generate the maximum amount of electricity possible while maintaining limiting tripping hazards to make maintenance (cleaning) of the solar panels fast, easy and safe.

Delivery from White Cap to our project site. Our account manager, Gino Attanasio, is taking good care of us.

Looking through the Atrium, the gable roofs are covered with Tyvek building wrap. Note how the evening sunshine is going into the kitchen through (what will be) the clerestory windows.

Looking South on the lower flat roof, admiring the Tyvek on the roofs. Note the chase for the conduit to the solar panels in the sunshine against the pony wall under the clerestory windows. Also, note the four insulated skylight curbs.

The upper flat roof is covered with Tyvek. Note the mounts for the solar panels in the lower left part of the photo. Also, of course, note the beautiful blue-sky California day.

The lower flat roof on the West side is covered with Tyvek. Note the insulated curbs for the skylights and the first clerestory window in the box at the top left of the photo.

It was satisfying to see the Tyvek on the gable roof at the front of the house. People driving North on Winchester Boulevard will see some progress on our house.

After two failed inspections, we passed our natural gas inspection on Wednesday, 08/18/10, so we could have the PG&E team connect our natural gas line to the main going up Via Sereno.  Today was [another] a big day.  After the natural gas was connected, Bryan ensured the natural gas lines were covered with 6 inches of sand.

Also, the team from Earth Bound Homes completed the chase for our solar AC and DC connections, installed a waterproof membrane at the connection to the gable roof and pony walls, and put Tyvek on the inside gable of two of our three gable roofs.

Laying In Our Natural Gas Connection

The two-person team from PG&E arrived at 8:45 am this morning.  Bill (the welder) and Larry worked safely and quickly to lay in our natural gas connection.  This was an interesting process to watch.

First, Larry did the ‘tail gate planning’, where he identified the closest emergency hospital (Good Samaritan Hospital off Los Gatos Boulevard) and noted the site-specific conditions.  For our project, these conditions included the potential of water below grade and the 15,000 volt underground electric cables within 18 inches of the natural gas main.  Larry documented these conditions on the tail gate board.

Then, they set to work.  All appropriate safety equipment was in place, including a fire extinguisher.  Then, Bill welded the vertical connection onto the live natural gas main.  This was a bit tense for Bryan to watch (yeah, welding a pipe containing natural gas at 57 PSI).  Meanwhile, Larry got the natural gas riser with 1/2 inch connection line and cut it to the approximate length, and they pressure-tested the assembly.

After Bill completed the welding, the connection has to cool before they could continue (approximately 20 minutes).  This allowed time to clean up the area, and place the riser assembly in the trench.

Bill tested the natural gas connection to the gas riser, which was ok.  Then, he cut into the live natural gas line, which allowed gas to flow into the gas riser.  Larry opened the valve slowly, to avoid triggering the emergency shut off valve, and allowed some gas to flow through the line.  This cleared any debris (dirt, sand, etc.) from the line.  Then, Larry closed the valve.

With the connection working, Bill then primed the main line and connection and tested all the joints with soapy water.  Ensuring there were no leaks, Bill wrapped the natural gas line and all metallic connections with the special tape (to avoid corrosion).

After loading up their tools and equipment, Bill and Larry gave Bryan the final instructions on covering the new natural gas line with six inches of sand, and then they left the job site.

It was 10:15 am.

Preparing to Install the Solar Mounts

Since we have a membrane roof on the flat roofs, we have to have all the penetrations completed.  With our 48 solar photovoltaic panels, we must have the mounts for the frames completed and in place as soon as we put down our Tyvek wrap over the flat roof.  This will allow Akeena Solar to install (with us), the brackets for the 32 solar photovoltaic panels (in 4 arrays of 8 panels each) on the upper flat roof.

Also, we need to have the conduits in place for the AC (from the 16 panels with Enphase micro-inverters on each individual panel) and the DC (from the 32 panels on the upper flat roof), all of which go through the SIP roof to the rigid conduit in the concrete wall that will take the electric cables to the East Mechanical room.

We’ve scheduled the installation of the solar mounts by Akeena Solar on the upper flat roof and the conduits going to the SIP roof for Friday.  Thus, the team from Earth Bound Homes has to have the Tyvek and other components in place so Akeena can do their work.

It’s all good.

The two-person team from PG&E just arrived. Bill and Larry will do the natural gas lay-in to the exposed natural gas main.

Bill starts welding the vertical connection to the natural gas line. This made Bryan a bit nervous, as welding a live natural gas line with 57 PSI just didn't seem prudent.

Bryan, with more courage, took a closer photo of Bill completing the weld to the live natural gas line.

Bill and Larry leaving the site at 10:15 am. It was a quick 90 minutes for them to complete the natural gas lay-in.

The completed connection. Bill was very careful to ensure that all of the nicks in the natural gas line covering were removed and wrapped with new material. There won't be any corrosion with this connection.

After Bill and Larry left, Bryan ensured the natural gas main and our connection were covered with at least 6 inches of sand. We hope Izzy will be available in the morning to help backfill and compact the trench to grade.

Our solar chase for the conduit from the gable and flat roofs, and to take the AC and DC lines to the East Mechanical room.

Our Tyvek covering the South side of the North gable.

Looking North, at the West side of the East gable.

Bryan was most proud of the natural gas lay-in today, and took photos from the roof.

The connection to the cistern can be completed now.

We are getting closer to putting the tapered insulation down on our flat roofs so we can put the membrane on and get water tight.  Before doing so, we verified that the SIP roof has no ‘voids’ in the insulation where the individual pieces come together. 

In anticipation of the next step, becoming weather tight, Bryan picked up the first of 72 boxes of windows so we could confirm the window preparation requirements.  Since we will be seeing Carole Murray tomorrow, it is important to show that we’re progressing and getting the windows out of her warehouse!  Also today, Bryan continued working with Izzy on ensuring the HDPE coming out of each concrete pier can be joined to create our ground loop.

At the end of the day, Gino Attanasio from White Cap dropped off two more 10-lb containers of expanding foam for us to use in tightening up our building envelope.

Picking Up Our First Window

We have 72 boxes of sliding glass doors and windows at Murray Window and Door.  We can’t install the sliding doors and windows until we are weather tight.  Well, we probably could install them but we are choosing not to.

In anticipation of the first clerestory window installation, we picked up one of the 16 windows.  This will allow us to identify exactly how the windows will ‘fit’ and how we will need to attach the windows.  While we have shop drawings, it is always good to have the actual item on hand to avoid potential problems.

After hoisting the window up and onto the roof, we were able to see exactly how the clerestory windows will fit.  This was important as we may have a conflict with the nail fins and edge trim in each of the four corners where the two clerestory windows come together.

Using Thermal Imaging to Verify Our Insulation Value

In our house, the SIP panels are connected on the roof with either wooden I beams or 6×12 splines.  In either case, there is a possibility of leaving ‘voids’ in the EPS foam at these locations.  If a void is left then the insulation value of the roof is compromised.  Voids will reduce the insulation value much more than thermal bridges, which is another problem that we want to avoid.

Today, we took the opportunity to engage Lorna Fear, with Visual Cue Thermal Imaging, to spend a couple hours going through our project to verify that we didn’t have any voids between our SIPs.  Bryan and Lorna worked together, with Bryan explaining how the SIP construction worked and Lorna reviewing the thermal images and identifying where potential problems could be.  Lorna is an expert at interpreting the thermal images and ’seeing’ where there are inconsistencies in the building envelope.

The thermal imaging identifies different surface temperatures and displays those differences with different colors.  Since heat goes from hot to cold, a surface temperature that is colder than surrounding surfaces may indicate that the energy is being drawn into the building, through a less-insulated condition than the surrounding area.  However, surfaces may also reflect thermal energy, thus showing very ‘hot’ surfaces that may hide other problems.

Given her experience, Lorna can identify where potential problems may occur with our insulation.  Bryan asked Lorna to identify all potential problems locations as we can deal with ‘false positives’ at this stage.  If we miss a problem, it could be there for the life of the building.

Removing Concrete for Our Ground Loop

Bryan spent the afternoon with Izzy chipping away at the top of 6 of the 12 concrete piers on the West side of the house.  Ken Martin, from Silicon Valley Mechanical, fine-tuned the design of the geothermal ground loop so there are two ground loops on the West side that include six concrete piers in each ground loop.

Connecting the individual loops in each pier requires two 90 degree fittings and a short length of HDPE.  Then, the piers need to be connected to each other in a daisy chain manner, with a supply and return for each pier.  For the physical connection, Matt Jung (88HVAC) identified that we need a one-inch space for the cold ring and then another 4 inches to weld the fittings on.  Thus, there must be at least five inches of clear space on the top of each concrete pier where the connections will be located.

All of the piers need to be checked for sufficient space and, where additional space is required, the concrete must be removed.  Removing concrete is noisy, difficult and time-consuming (just ask Bryan). 

Picking up the first of 72 boxes from Murray Window and Door. Bryan was smiling as he picked up the first box, especially since we will be seeing Carole Murray on Saturday afternoon at Black Ridge Vineyards.

We have the window on the roof, and unpackaged it so we could see exactly how it fit and what the potential issues would be when installing it (and the other 15 clerestory windows).

Lorna, using her Fluke infrared thermal imaging camera, reviewing the South side of the South Gable over the Master Suite.

Lorna uses her Fluke infrared thermal imaging camera to review the upper flat SIP roof for voids.

This is the thermal image with the surrounding image around it. You can see the surface temperatures with the scale on the right hand side.

Lorna using her Fluke infrared thermal imaging camera, identified potential locations where voids may be on the upper flat roof that need to be investigated.

On this thermal image you can see where the warm and cool locations are. This thermal image shows that there may be voids between the SIPs that need to be filled with expanding foam.

Izzy and Bryan spent several hours removing concrete from the top of the concrete piers so the ground loops can be connected by 88HVAC. Matt Jung of 88HVAC will be coming by the job site on Sunday to verify if additional concrete needs to be removed.