If you were an Energy Advisor, your day might go a little like this:
You’re out on the road for most of the day, but before you go out there is some planning to do for the rest of the week.
Your first task of the day is to confirm your site visits. Make sure you have the address and directions so that you can arrive on time. You have two of them. One is for an existing house, where you will be expected to observe the condition of the house as well as eventually supply a report that outlines recommendations for energy savings. The other house has just been built, and your visit will be to confirm that it includes the energy conservation measures it was modelled with to get a specific energy target.
The second task is to review emails from your Service Organization, or check in with your Service Organization Manager to discuss the week’s schedule.
The third task of the day is to get on the phone and set up site visits for next week and do a pre-evaluation interview for tomorrow’s site visits. Except Friday, that’s the day you are in the office to do energy modelling, write reports, and submit files to NRCan.
PREPARING FOR SITE VISITS
Before you leave your office, or maybe your home, it’s time to check that you have a complete site visit kit in your vehicle: blower door apparatus, infrared camera, data collection material (writing utensils, clipboard with fresh data collection sheets, phone and/or tablet, digital camera, and charger(s)), ladder, flashlight and/or trouble light, measuring devices (tape measure/electronic measure, thermometer, air movement indicator, low-e detector), extra batteries for any non-charging equipment.
Here’s some more gear that will help you do the job efficiently and professionally:
Non-metallic knitting needle or wood skewer to measure insulation thickness
A toolkit with multibit screwdriver, hammer, pliers and battery operated drill
A utility knife
A mirror with an telescoping handle so you can see into tight places
Tissues, wipes, and paper towels
To keep your client’s home mess free:
Non marking indoor footwear
Tarps or drop cloths
Once you’ve checked over your toolkit, you need to look at your personal protection equipment (PPE). You must have a supply of N100/HEPA filter masks or a half-mask respirator so you can go up into attics. If you were doing a blower door service on a construction or renovation site, you’d also have to have your hard hat, safety eyewear, and protective footgear. Today’s site visits are to completed houses, so you won’t need to wear them.
SITE VISIT #1: AN EXISTING HOUSE
When you arrive at the house, introduce yourself to the homeowner and make sure you’re not blocking the driveway or entrance. Let the homeowner know how long the evaluation will take, that you will be taking photos throughout the evaluation, and that you will be starting outside and then coming in. You will want to know which door you can use for the blower door apparatus, and ensure you have access to the attic and basement as requested in your pre-evaluation interview. Have all your paperwork in hand and provide to the homeowner.
You will take photos of the outside of the house. This gives you validation of pre- and post- renovation conditions. Your photos include each side of the house showing the whole wall surface from grade to rooftop. You include some extra photos that show windows hidden or obscured by bump outs on one side.
From the exterior, you note the general information about the house:
Cardinal or ordinal direction that the front of the house faces
Number of storeys and configuration
Any atypical loads (heated garage, hot tub, swimming pool, car charging station)
INTERIOR EVALUATION AND BLOWER DOOR TEST
Inside, as you move through the house, you continue making the photographic record of the house with shots of basement walls, crawlspaces, headers, and attic showing the insulation. You take two photos of each piece of mechanical equipment, one showing the unit and the other showing the nameplate. This house doesn’t have a heat pump or air conditioner, so you don’t have to take photos of any outdoor units.
You need to take a photo of the blower door installed at the house as well.
Once you have finished working outside, you need to determine the building envelope characteristics:
Thermal Resistance – ceilings, above grade walls, floor headers and rim joists, exposed floor, exterior doors, floors above crawl spaces,below-grade wall assemblies and floors on ground.
Doors, windows and skylights – height, width, door construction, window configurations including number of panes of glazing, low-e coatings, gas fills, spacer types, and framing materials as well as orientation, header heights and overhang widths.
Heated Floor Area – you calculate this as per the current EnerGuide Rating System – Technical Procedures, section 3.5
Mechanical Systems – this includes existing space heating and cooling systems, whole house ventilation equipment like heat recovery ventilators, as well as exhaust fans in bathrooms and in the kitchen, and the domestic hot water equipment as well as drainwater heat recovery systems.
Renewable energy system – if a PV system or a solar thermal system is in place, you will record the information showing the system capacity and efficiency.
DATA COLLECTION: SKETCHES AND MEASUREMENTS
As you collect information about the house characteristics, you will also be creating a set of sketches with measurements and dimensions of the interior of the house. You’ve got to take some time on these, as the sketches of each floor and portion of the house have to be clear and complete so that the model can be replicated if it goes through the quality assurance process. Your Service Organization has created a series of acceptable symbols, codes, and short cuts that you can use to streamline this part of the evaluation.
Starting in the basement, you work your way up through the house. This house is non-rectangular, so you know that you will be developing a more complex model. You measure the total wall perimeter, the average height of the pony wall and the height of the foundation so that you can input area and volume measurements. Part of this basement has a pony wall, and the other part is full-height foundation. There are a couple of different wall types in the full height basement area - one is a stand-off 2x4 wall to the inside of the concrete foundation, with R12 fiberglass batt in it, and the other is 2 inches of Type II Expanded Polystyrene. You note that 80% of the foundation has the standoff wall and the other 20% is covered with the Type II foam.
You sketch in the windows in the pony wall section, measure them, and note that they are horizontal sliders with two panes of glass, but no low-e coating, air fill, and metal spacers. They have vinyl frames.
Moving up to the main floors (there are two in this house), you sketch up the floor plan and measure the exposed perimeter of the walls and floor headers, the wall height and any exposed floors, the upper floor flat and sloped ceiling areas as well as the average height of the gable walls.
Then you sketch in the windows and doors of the house onto the wall drawing, in the correct orientation, measure them and note that half of them are vertical sliders like those in the basement but the other half are newer, with a low-e coating, argon fill, insulating spacers, and vinyl frames.
You note the heated floor area below grade and the above grade total.
There are some sloped ceiling areas on the upper floor, and so you need to measure the area of the sloped ceiling separately from the flat ceiling. And then it’s up into the attic! You record the eave length, the structure, the size and spacing of the framing, the insulation thickness and the interior finish.
THE BLOWER DOOR TEST
You run the air tightness test to depressurize the house and bring it to test conditions and take a series of pressure readings. The data from this test will be used by the modelling software to approximate natural air leakage rates and the accompanying heat loss and heat gains. The pressure readings, along with house volume and exterior surface area are used to calculate:
Air change rate at 50 Pa (ACH @ 50 Pa).
Equivalent leakage area at 10 Pa (ELA @ 10 Pa).
Normalized leakage area at 10 Pa (NLA @ 10 Pa).
After you’ve done the airtightness test, you walk through the house with the blower door running at a lower pressure and identify air leakage locations. You will note the ones that need to be addressed in your air sealing recommendations. This is a great opportunity to educate the homeowner, who is curious about what you’re doing. Using your infrared camera, you show them the temperature difference that indicates where insulation is missing, and the characteristic ‘feathers’ that show air movement, in this case, at the headers between the main and second floor on the front of the house where the porch attaches to the side of the house.
You wrap up your site visit by giving the homeowner some publications that your Service Organization supplies for air sealing and moisture mitigation. You let them know when they can expect to get their report that includes your recommendations for energy conservation measures. After some more conversation as you pack up your gear, you say goodbye and head off to the next site visit.
SITE VISIT #2: THE NEW HOUSE
You did the initial energy modelling on this house. Your job today is to inspect that the house was built to match the energy model in terms of insulation and air sealing, as well as space conditioning equipment, ventilation and domestic hot water that meet the sizing and efficiency you specified. In addition, you need to review the plans to ensure that there were no major changes in window sizes or plan shape that were made after you did the model.
While your first visit was almost three hours of effort, this one will be about an hour. The builder is waiting for you at the door. You review the plans and ask a few questions of the builder, who indicates the house was built as per the plans. As in your first site visit today, you start on the exterior, take the required photographs and note the primary exterior features. Then, inside the house, you need to record the building envelope characteristics, document the mechanical system information, and carry out a blower door test. In this case, this is a builder you have worked with over several houses and have helped them and their crew improve their air sealing techniques. The blower door test results are lower than what you used in the original energy model. That’s a great result. You tidy up your gear and say goodbye to the builder, letting them know that you will provide the final evaluation and report within the week. Done.
ENDING THE DAY
You get back to the office and make sure that any notes you made to yourself are clear, and add in any observations from either site visit that you recall. There’s time in the day to revise and finalize the energy model from site visit #2, generate the report, and submit the file, so you do that. This means that on Friday you can focus on the energy model for site visit #1 if you don’t have time to get it finished tomorrow before your next site visit, which is scheduled for the early afternoon.