Online Energy Auditor Certification Training Course
  • HOME
  • PRACTICE EXAMS
    • BPI PRACTICE EXAMS
    • FREE BPI EXAM QUESTIONS
    • HERS PRACTICE EXAMS
  • NEWBIES
    • WHAT DOES IT LOOK LIKE?
    • HOW DO I DO...?
    • HOW TO CHOOSE A BPI TRAINING CENTER
    • STEP-BY-STEP GUIDE
  • STUDY GUIDES
    • BPI WRITTEN EXAM >
      • Section 1 Building Science Fundamentals >
        • 1a. Basic Terms & Definitions >
          • 1. Airflow in Buildings
          • 2. Equipment Efficiencies
          • 3. Power and Energy
          • 4. Effective Leakage Area
          • 5. Area Weighted R-Value
          • 6. Baseload / Seasonal Energy Use
          • 7. Driving Forces (Including Natural and Mechanical)
          • 8. Behavior of Radiation
          • 9. Thermal Resistance / Transmittance: R and U Values
          • 10. Latent / Sensible Heat
          • 11. Total Equivalent Length
          • 12. Dehumidification / Humidification
          • 13. Convert Pressure Units
          • 14. Thermal Bridges
          • 15. Pressure Boundary
          • 16. Stack Effect
          • 17. Exfiltration and Infiltration
          • 18. Natural / Mechanical Ventilation
          • 19. Net Free Area
          • 20. Input & Output Capacity
          • 21. Peak Electrical Demand
          • 22. Permeability and Perm Rating
          • 23. Standby Loss
          • 24. IAQ (indoor air quality): Moisture, CO, Dust
        • 1b. Principals of Energy, Air & Moisture Thermodynamics >
          • 1. Thermodynamics: Conduction, Convection, Radiation, ΔT
          • 2. Factors That Affect Insulation Performance
          • 3. BPI certification online with BPI practice exams and study guides.
          • 4. Heat Gain / Loss
          • 5. Power and Energy
          • 6. Moisture Transport Mechanisms
          • 7. Identify Areas of Highest Relative Humidity
          • 8. Principles of Combustion
        • 1c. Combustion Safety >
          • 1. Combustion Analysis
          • 2. Carbon Monoxide (CO) Testing
          • 3. Combustion Appliance Venting, Draft, Combustion Air & Sizing
          • 4. Understand Combustion Safety Issues
      • Section 2 Buildings and Their Systems >
        • 2a. Building Components >
          • 1. Identify basic duct configurations and components
          • 2. Identify Basic Hydronic Distribution Configurations and Components
          • 3. Identify Basic Structural Components of Residential Construction
          • 4. Thermal Boundaries and Insulation Applications
          • 5. Basic Electrical Components and Safety Considerations
          • 6. Basic Fuel Delivery Systems and Safety Considerations
          • 7. Basic bulk water management components (drainage plumbing gutters sumps etc)
          • 8. Vapor barriers/retarders
          • 9. Radiant Barrier Principles and Installations
          • 10. Understand Fenestration Types and Efficiencies
          • 11. Understand Issues Involved With Basements, Crawlspaces, Slabs, Attics, Attached Garages, Interstitial Cavities, and Bypasses
          • 12. Understand Issues Involved With Ventilation Equipment
          • 13. Understand Basic Heating / Cooling Equipment Components Controls and Operation
          • 14. Understand Basic DHW Equipment Components Controls and Operation
          • 15. Identify Common Mechanical Safety Controls
          • 16. Identify Insulation Types and R-Values
          • 17. Understand Various Mechanical Ventilation Equipment and Strategies: Spot, ERV, HRV
        • 2b. Conservation Strategies >
          • 1. Appropriate Insulation Applications and Installation Based On Existing Conditions
          • 2. Opportunity for ENERGY STAR Lighting and Appliances
          • 3. Identify Duct Sealing Opportunities and Applications
          • 4. Understand Importance of Air Leakage Control and Remediation Procedures
          • 5. Blower Door-Guided Air Sealing Techniques
          • 6. Water Conservation Devices and Strategies
          • 7. Domestic Hot Water (DHW) Conservation Strategies
          • 8. Heating & Cooling Efficiency Applications
          • 9. Proper Use of Modeling to Determine Heating and Cooling Equipment Sizing and Appropriate Energy
          • 10. Understand the Use of Utility History Analysis in Conservation Strategies
          • 11. Appropriate Applications For Sealed Crawlspaces Basements and Attics
          • 12. Identify / Understand High Density Cellulose
          • 13. Appropriate Applications for Fenestration Upgrades Including Modification or Replacement
        • 2c. Comprehensive Building Assessment Process >
          • 1. Determine Areas of Customer Complaints / Concerns in Interview
          • 2. Understand / Recognize Need For Conducting Appropriate Diagnostic Procedures
          • 3. Interaction Between Mechanical Systems, Envelope Systems and Occupant Behavior
        • 2d. Design Considerations >
          • 1. Appropriate Insulation Applications Based On Existing Conditions
          • 2. Understand Fire Codes as Necessary to Apply Home Performance in a Code-Approved Manner
          • 3. Understand / Recognize Building Locations Where Opportunities for Retrofit Materials
          • 4. Understand Climate Specific Concerns
          • 5. Understand Indoor Environment Considerations for the Environmentally Sensitive
          • 6. Understand Impact of Building Orientation, Landscape Drainage, and Grading
          • 7. Opportunity Potential Renewable Energy Applications: Geothermal, Photovoltaic, Wind
          • 8. Understand Impact of Shading on Heating / Cooling Loads
          • 9. Awareness for Solar Gain Reduction / Solar Gain Opportunities
          • 10. Understand Need for Modeling Various Options For Efficiency Upgrades
      • Section 3 Measurement & Verification of Building Performance >
        • Section 3a Measurement & Verification of Building Performance >
          • 1. Air Leakage Test Results
          • 2. Understand Building Shell / Envelope Leakage
          • 3. Apply Fundamental Construction Mathematics and Unit Conversions
          • 4. Calculate Building Tightness Levels (Minimum Ventilation Requirements)
          • 5. Calculate Heating Degree Days and Cooling Degree Days
          • 6. Identify Proper Appliance and Combustion Appliance Venting
          • 7. Ventilation calculations and strategies
          • 8. Proper methods for identifying / testing fuel leaks
          • 9. Blower door setup, accurate measurement and interpretation of results
          • 10. Combustion Appliance Zone (CAZ): depressurization, spillage, draft, Carbon Monoxide (ambient and flue)
          • 11. Carbon Monoxide (CO) evaluation: ambient
          • 12. Proper applications and use of temperature measuring devices
          • 13. Pressure pan and room to room pressure diagnostics
          • 14. Recognize contributing factors to comfort problems
          • 15. Inspect for areas containing moisture or bulk water in undesirable locations
          • 16. Understand and inspect for basic electric safety (e.g. frayed wires, open boxes, etc)
      • Section 4 BPI National Standards & Project Specifications >
        • 1. Understand applicability content and intent of BPI National Standards – Do no harm, make buildings more healthy, comfortable, durable and energy efficient
        • 2. Recognize need for a professional local/state/national codes evaluation
        • 3. Be able to specify appropriate materials and processes needed for building performance projects
      • Section 5 Analyzing Buildings Systems >
        • 1. Recognize need for air sealing measures and their impact on other building systems
        • 2. Recognize need for mechanical equipment improvements
        • 3. Understand blower door use for identifying critical air sealing areas
        • 4. Apply blower door test results and Building Tightness Limit (minimum ventilation requirements) in development of improvement strategies
        • 5. Using combustion analysis and safety testing results to develop appropriate recommendations
        • 6. Determine appropriate method for assessing wall insulation levels
        • 7. Equipment control strategies for maximizing occupant comfort and minimizing energy consumption
      • Section 6 Conduct and Communications >
        • 6a. Conservation strategies
        • 6b. Personal Safety & Work Practices >
          • 1. Locations in which to identify indoor air quality issues
          • 2. Material Safety Data Sheets
          • 3. Isolation procedures for household pollutants
          • 4. Practice building science within your limits of professional competency
          • 5. Precautions when working around chemical biological and other potential hazards
          • 6. Understand role and responsibilities of the building analyst professional
    • BPI FIELD EXAM >
      • How To Put The House Under Worst Case & CAZ
      • What's What? Pa, CFM, CFM50, CAZ, Draft, Room Pressure
      • What To Know In The Attic
      • What To Know In The House
    • BLOWER DOOR TEST >
      • Manometer Setup
    • BPI BUILDING ANALYST STANDARDS >
      • BPI Standards Decoded
  • ESSENTIALS
    • HELP, I HATE MATH!
    • AUDITOR TO CREW COMMUNICATION
    • COMMON AUDITOR / CREW MISTAKES
    • RUN LIKE HELL
    • CONTACT
  • AFTER THE EXAM
    • START A HOME PERFORMANCE BUSINESS
    • FREE ENERGY AUDITOR MINI COURSE
    • RESOURCES
  • NEWSLETTER
  • BLOG

Passing the BPI Exam With Energy Auditor Training

FREE BPI PRACTICE EXAM

Picture

PUT YOUR HOME PERFORMANCE BUSINESS ON ROCKET FUEL

Picture

ENERGY AUDITOR NEWSLETTER

Get the only Energy Auditor Marketing Newsletter with monthly strategies and tactics to grow your home performance business.

BPI Written Exam - Section 1 Building Science Fundamentals

7. Understand Driving Forces (Including Natural and Mechanical: Pressure, Temperature, Moisture Differential

Terms: 

  1. Pressure - pressure moves from high to low. Think of a pop can.
  2. Temperature - heat moves from hot to cold. Think of a stove.
  3. Moisture - water moves from wet to dry. Think paper towel
This is one of my favorite sections because it is so easy to memorize but it has deep implications and can make you look really good in front of a homeowner when explaining why their home gets so dusty, room so hot or floor so cold.  The terms above will definitely be on the BPI test, so I would commit them to memory.
Picture
Natural forces include:
  1. Wind - wind forces can really drive air leakage in a home, just has house pressures from AHUs (air handler units).  A homeowner may really notice their homes' air leakage if their city is windy relatively often and give you valuable insights during the interview as well as touching on their hot spots.
  2. Outside temperature - BPI has specific standards for each climate zone.  Depending on where you are you will have to deal with humidity, moisture and mold.
  3. Rain - during the walk through of the exterior of a home, you should be inspecting for proper drainage, that everything slopes away from the home to prevent mold and moisture build up.  Same thing with the roof line. 
  4. Outside moisture - water moves from wet to dry, so any stagnation of water will eventually enter the house and begin to rot the interior walls.
  5. The stack effect - the stack effect is a natural process that occurs in homes and buildings where colder air enters around the floor or basement of a home and naturally moves up and exits through the top of the home.  It is most pronounced in 3 story homes.  How to do reduce or stop the stack effect?  By air sealing (see paragraph below on holes and pressures).  If you find a home with a crawlspace and original wood floors and the house is leaky, you can educate the homeowner on the stack effect as your case for air sealing. Just imagine what kind of air they are breathing in the house, it's basically the crawl space air including the rodents, feces, insects and possibly mold!
Picture
Mechanical forces include:
  1. The heating and cooling system - if you don't live in a windy climate, the AHU is the next biggest driver of air leakage, either from 1) just the whole house being pressurized or depressurized; 2) from specific room pressures being too high or too low; 3) the ductwork, the AHU really pushes a lot of pressure through the ductwork so any holes in the ductwork tend to be more exaggerated 
  2. Exhaust fans (on a tight home or if they are large scale)
  3. Attic fans (on a tight home)
  4. Inside moisture (not really mechanical but you need to know it) - this is where you need to be aware if you come across a tight home with no exhaust fans or way to remove moisture to the outside.  Interior moisture left alone or constantly present can create mold growth.

You really need to have these topics in this whole section in the front of your mind the entire time you are performing an energy audit.  It is too easy for novice energy auditors to concentrate just on the motions, running a blower door test, inspecting the attic for open wall chases and misalignments, walking through the house with an IR camera and think they are doing a good audit.  Without understanding these concepts and their applications, an auditor is just putting lipstick on pig.

What drives air leakage?

The answer is a pressure difference and a hole and you need both of them to get air leakage, if you stop one, you stop the other.  

The pressure difference comes from MECHANICAL FORCES like the AHU (air handler unit) or exhaust fans or attic fans if the home is very tight or NATURAL FORCES like wind or the stack effect.

The AHU creates a lot of pressure when it kicks on, enough pressure is generated to blow air through all the ductwork up 3 stories or across the house 30 feet.  That's why if you are doing a time-and materials contract always start sealing the ductwork connections closest to the AHU, because it is under the highest pressure.  Leakage closer to the AHU under 100 Pa of pressure is much more important than leakage 30 feet downstream under 10 Pa of pressure.  The room pressure should also be considered because opening and closing doors is essentially like putting a huge dampener on the ductwork to that room if the room pressure is high.  High room pressures can contribute to air leakage, dust, allergens and make the HVAC system work harder.  What is a high room pressure?  You may notice that doors close by themselves when the HVAC system kicks on, that is because it has a high room pressure.  By relieving the room's pressure, you reduce the amount of air leaking, dust and increase circulation back to the return.

An exhaust fan may not be a blower door, but on a tight home, they can definitely have an adverse effect. A tight home is much more sensitive to doors closing and small fans running than a leaky home because it creates a vacuum effect.  This is bad because outside air can come into the home through existing leakage or worse carbon monoxide can enter from an attached garage or backdraft down a water heater or furnace flue and enter the home.  You may not have to worry about smaller exhaust fans, but when you go to newer homes that have commercial range hoods suitable for Iron Chef, you really need to be aware. 

I heard a new Energy Star home was built so tight, that the toilet flushed when the front door was closed... I don't know if that is true, but it is a funny story.  Attic fans have been shown to cause the same adverse effects where the attic fan will cause gas appliances to backdraft into the home.  Now that is scary.

A hole is any connection to the outside or attic space from leaky windows and doors, drywall gaps around exhaust fans, registers and canned lights, and electrical and plumbing penetrations.

So to stop air leakage you can either air seal the home or pressure balance the home.  Since usually the AHU is going to create some negative or positive pressure every time it runs, air sealing is usually easier (excluding room pressures).

Pressure moves from high to low

Examples are:

  1. Your AHU, the air closest to the blower is under the highest pressure (therefore the leaks closet to the AHU are the highest priority).  
  2. Room pressures, when you shut interior doors, you are essentially putting a dampener on that duct line unless there is a way for the pressure or air to escape back to the return by either a transfer grille, jump duct or return duct.
  3. During an energy auditors combustion safety tests, the home gets put under the most negative pressure possible (aka worst case) for each space where a gas appliance is located (the "CAZ").  This usually means turning on the all exhaust fans, AHU and dryer to create a negative pressure in the house in attempt to backdraft the appliances so we can catch a potential H&S hazard before it actually happens.
  4. Dominant duct leakage test can tell us if there is more leakage on the supply side (negative number) or the return side (positive number) of a duct system.
  5. The outside wind forces can put out homes under a positive pressure on one side, and a negative pressure on the opposite side.

Temperature moves from hot to cold

Examples are: 

  1. The heat from 150 degree attics in Phoenix entering through uninsulated kneewalls
  2. A room that has direct western exposure with lots of windows will get hot in the afternoon
  3. Our body heat is being removed off our skin into the atmosphere, that is why we get cold

Moisture moves from wet to dry

Examples are

  1. Water adsorbing through the drywall from a damp soil area from a hose leak
  2. Steam from a hot shower adsorbing through the walls to cause dry rot

Next Section

  1. 1a. Basic terms and definitions
    1. Understand airflow in buildings / ducts: CFM, CFM50, CFM25, ACHn, ACH50, FPM
    2. Understand equipment efficiencies: AFUE, SSE, SEER, EER, HSPF
    3. Understand power and energy: watts, BTU/hr, ton of refrigeration  watt-hours, BTU, therm, decatherm
    4. Understand effective leakage area
    5. Understand area weighted R-Value
    6. Understand baseload / seasonal energy use
    7. Understand driving forces (including natural and mechanical: Pressure, temperature, moisture differential
    8. Understand behavior of radiation: emissivity, reflectivity, absorbtivity
    9. Understand thermal resistance / transmittance: R and U Values; including conversions
    10. Understand latent / Sensible heat: evaporation, condensation / specific heat, heat capacity
    11. Understand total equivalent length
    12. Understand basics of dehumidification / Humidification as well as measurement equipment
    13. Understand and convert Pressure units: Inches of Water Column (iwc), Pascal (Pa)
    14. Understand, identify thermal bridges
    15. Understand pressure boundary 
    16. Understand/define stack effect 
    17. Understand and define exfiltration and infiltration 
    18. Natural / mechanical ventilation 
    19. Understand net free area 
    20. Understand input / output capacity 
    21. Understand peak electrical demand 
    22. Understand permeability and perm rating 
    23. Understand standby loss 
    24. IAQ (indoor air quality): moisture, CO, dust
1b. Principals of energy, air & moisture
  1. Thermodynamics: conduction, convection, radiation, ΔT including air movement due to temperature gradients
  2. Factors that affect insulation performance: density, installation, moisture
  3. House pressurization/depressurization by various forces
  4. Heat gain / loss: internal, solar, heat transmission, air leakage 
  5. Power and energy: BTU content of fuels, capacity of combustion appliances and electrical appliances 
  6. Moisture transport mechanisms: bulk water, air leakage, diffusion, capillary action 
  7. Identify areas of highest relative humidity 
  8. Principles of combustion: combustion analysis, CO 
1c. Combustion science
  1. Combustion analysis: oxygen, flue-gas temperature, carbon monoxide 
  2. Carbon Monoxide (CO) testing of combustion appliances 
  3. Basics of: Combustion appliance venting, draft, and combustion air including identification of proper sizing/vent tables 
  4. Understand combustion safety issues: Combustion air, draft, worst case / baseline depressurization, spillage, backdrafting, unvented combustion appliances 
Quick Links

1. BPI Written Exam
2. BPI Field Exam
3. Blower Door Test 
4. BPI Standards

The main topics of the BPI BA exam are listed out below.  Click on a link that interests you, or you need some brushing up on to learn more on each subject.

1. Building Science Fundamentals
1a. Basic terms and definitions
1b. Principals of energy, air & moisture
1c. Combustion science

2. Buildings and Their Systems
2a. Building components
2b. Conservation strategies
2c. Comprehensive building assessment process
2d. Design considerations

3. Measurement and Verification of Building Performance
3a. Applied diagnostics and troubleshooting

4. BPI National Standards and Project Specifications
4a. Comprehensive building assessment

5. Analyzing Buildings Systems
5a. Comprehensive building assessment
5b. Appliances and lighting

6. Conduct and communications
6a. Conservation strategies
Copyright 2023 Building Science Training Center LLC
For Trainers - License BPI Course Material & Slides
Terms and Conditions