Verifying Our Insulation Performance and Value
Friday, August 20th, 2010We 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.
