HERS Testing, Registration, and Energy Compliance

Building Energy Compliance Testing’s qualified HERS raters offer a variety of energy efficiency services. We serve the San Francisco Bay Area building industry for both commercial and residential buildings. Our services include air duct testing, duct leakage testing, blower door tests, room by room airflow tests, refrigerant charge tests, total airflow tests, and fan watt draw tests. We also provide verification of existing conditions reports, registration, consulting and assistance with building healthy, comfortable and high performance buildings. We provie Home Energy Ratings, GreenPoint Rated certification, and California energy code and Calgreen. Which are required HVAC load calculations, Manual J, duct design Manual D and equipment selection Manual S.

Home Energy Rating System (HERS)

We provide the full range of state required HERS testing and registration for building alterations including new HVAC, additions to existing HVAC, duct testing, and new construction.

The HERS Program was implemented to address construction defects and equipment installations that had not been done correctly. The Whole House Home Energy Rating is on a scale of 0 to 250 that represents energy efficiency relative to a reference home that represents the Title 24 Building Energy Efficiency Standards’ requirements.

Build It Green – GreenPoint Rated

GreenPoint Rated is the most trusted independent green home certification program in California, providing proof that a home is healthy, comfortable, durable, and resource efficient. More than 31,000 homes have been rated through the program, administered by Build It Green.

GreenPoint Rated verifies a level of green construction measures including resource conservation and proof of use of materials without formaldehyde, VOCs and other unhealthy compounds.

Haight-Ashbury Energy Checkup

BECT Cool Roof Upgrade

QII, Quality Insulation Installation

Blower Door: Tool to Air Seal Homes

Things Our Clients Said Today

Green Point Rating - BECT

CalGreen 2016 Non Res

Code Required Load Calculations, Equipment Selection And Duct Design 5/7/19

Cost of Course

Outline for class:

Heating/Cooling Load calculations, HVAC equipment selection and duct design: Learning basics of powerful & easy-to-use software that allows HVAC contractors and installers to build home comfort systems that meet code achieved with ACCA Manual J, Manual S and Manual D.

Course Outcomes: To get HVAC contractors comfortable performing load calcs, equipment selection and duct design as required by California Energy Code by using wright-soft software. In the program students will learn what is required by code, ACCA Manual J, Manual S and Manual D. Students will learn how current code directs designers to build high performance comfort system that deliver  By end of class, students will be able to create a simple house diagram with separate rooms each with required air CFM to maintain temperature range. Diagram will show house rooms with dimensions in feet, duct diagrams, duct sizes, furnace, windows, doors and return air grill.

Software Requirement:

upload free version of Wrightsoft software for student project.

Hardware Requirement:

Required computer and monitors windows 10 and large monitor, (two large monitors are better) internet access.

Instructor: George Matthews, Building Energy Compliance Testing

Module 1

What California building energy code requires and why. ACCA Manual J, Manual S and Manual D or ASHRAE equivalent are required by code before installing an HVAC comfort system.


  • Student will learn basic energy code requirements for California RE: HVAC.
  • Student will become familiar with ACCA Manual J, Manual S and Manual D.
  • Student will understand  where to use Manaul J, Manual S and Manual D.



Module 2

Downloading Wrightsoft software, free student version, and installing on machine. Become familiar with palate of choices such as draw line, draw square, specify feet/inch grid, add windows and doors. Become familiar with or review system of “point and click” and “drag and drop” drafting If not already.


  • Student will download and install Wrightsoft software
  • Student will become familiar with palate of choices
  • Student will practice the review system



Module 3

Perform home energy assessment to gain knowledge of energy loads, heating and cooling, to overcome. Students will need to document a house’s size by measuring every room and plotting on paper diagram such as large format grid paper. Every room gets measured in feet/inches and conveyed to sketch. Use digital measurement device like Bosch compact Laser Measure device.

Document crawlspace or slab and R value of insulation, repeat for walls and attics. Measure windows and note frame material and window pane number and type of coating such as low e. Document attic insulation and existing HVAC duct system if it matters to upcoming system design. Learn to make some assumptions of air leakinesss/tightness. For extra credit, do blower door test to assess air tightness of shell or envelope.

Make a clear diagram with all information as this will be translated into your digital energy model.

Module 4 Input data to program

Take sketch of house with interior room dimensions to computer and begin to transfer data into 2D digital model that is simple to create. Build one room at a time

Input insulation values into attic, walls and floors.

Module 5 Manual J – Load Calcs

From newly created digital sketch model navigate to load calc center and look at the load numbers for heating and cooling. Input correct geographical climate data, heating degree days and cooling degree days. Find the number of BTUs and move on to finding equipment that fits those parameters.

Module 6 Equipment Selection,

Find a few different furnaces that you think will work to supply the correct amount of air flow, BTUs heating and cooling. Download the equipment’s performance numbers from the spec sheet on the manufacturer’s website. Compare and contrast the different performance levels of the machines. Compare motors and specs such as “air-tight box” and especially static pressure at X airflow. Static pressure is huge here. We must get it right as we will be adding the resistance of all the ducting, plenums, elbows and wyes in the forced air system.

Module 7 Design your ducts.

This is really the fun part of the class. Digitally drafting the duct starting at the AHU and terminating in each room exactly where you think they will both fit and work best. Drag registers to their location. Click, drag and drop lines for ducts and build your system. Click the command and watch each duct populate with CFM that duct will have to move to get the perfect amount of air and the diameter of the duct to the inch. No more guessing. You might get 4, 5 and 7 inch ducts depending on the needed airflow.

Module 8 Register Grills – How much resistance? What Model/Brand? Performance thereof.

Learn the difference in resistance in grills and how much of their surface area is actually open space air can course through or block. This is not in the California energy code but the quest for efficiency, comfort and quiet make it smart to control the air in optimal fashion.

Module 9 Feedback Testing

After fabrication of system, test airflow, leakage and static pressure numbers. Measure airflow from every register and compare to plan. Is it sufficient? Does system leak 5% or less? Does system move 350 CFM per ton? (Hopefully more!). Is the Watts/CFM less than 0.58 watts/CFM. If airflow is not close, adjust dampers installed at plenum on each duct run start coller.

Module 10  Beyond the code compliance: Productivity, efficiency, quality control tool, sales tool.

Using Wrightsoft as a money making tool that sets you apart from your competition in create value for each job. Reducing callbacks through quality control of commissioning system before handing it over to client. Develop relationship with client.

Create a detailed shopping list for complete systems and one trip to HVAC supplier. Get pricing from complete and detailed list in a format one can email to supplier. Saves time.

Create detailed sales report to make your clients confident In your professional, proposal.

Guarantee that this is state-of-the-art system performance design that is more comfortable, creates better air quality than any HVAC system they ever had while being highly economical to run.

If you want, you can figure out how much it will cost them per year to run their heating and cooling system.

Module 11 Continuous Fresh Air Ventilation systems for homes. HRVs. How to spec and design systems to bring in HEPA air to one’s home.

To sign up, Contact Building Energy Compliance Testing

George Matthews

Dear Customer, This Is Our Approach To Bringing More Value To Your Energy Compliance Reports 5/7/19

Doing load calculations and duct design is required by the energy code, Title 24, part 6 and CalGreen Title 24 part 11. Many building departments don’t know this, but they do know they need a CF1R energy report. You are familiar with the energy report that you get from energy consultants before you can get a permit to add on, etc.

The same data-set is used for both so we do the work in Wrightsoft which does load calcs and duct (manual J, D and S) design and assists with equipment selection. We then export that dataset into EnergyPro and, after a few modifications, we generate the CF1R PRF-1. We feel that we can offer our clients a two-fer this way and get them more value for their energy compliance budget.

We started doing Wrightsoft after years of watching air conditioner installations fail (over 80%+!) because HVAC contractors don’t do the math and don’t know how to build energy models like in Wrightsoft. This was an attempt to follow the code and design systems that work properly and pass code mandated HERS tests.

We also use the kind of duct designs one can learn at PG&E’s Pacific Energy Center in the class, “Optimizing Residential Duct Systems”. Keeping the ducts inside the conditioned shell and optimizing airflow makes for better operating systems that provide more comfort at lower cost. We also design our systems to be able to run properly with restrictive MERV 13 filters which filter out pollen, pet dander, wood smoke and PM2.5 particles for our clients with respiratory concerns.

We think that pulling it all together for our clients creates better housing that is healthier, more comfortable, durable and less costly to operate. We hope you agree.

George Matthews

Go Electric, Step Off The Gas 1/19/19

BECT just went electric. We got an electric vehicle. It is a joy to drive and uses no petroleum. It feels great to ride smooth with no gears and not have any green house gasses out the exhaust pipe or my dollars flowing to Saudi Arabia.

You can get off of the natural gas at your house with BECT’s help.

We’ve done about 40 load calculations and duct design for Bay Area architects and homeowners so far. Getting to know the size of what Bay Area homes actually need in a furnace, heat pump or air conditioner has been eye opening. Turns out that most all HVAC contractors install a 60K or 80K furnace into a house without much thought. If one actually crunches the numbers, you learn that that houses might only need 24 or 30 or 36 thousand BTUs of heat to keep warm and comfortable on the coldest day of the year.

What this means is that Bay Area homes are a perfect match for heat pumps. These are all electric devices that extract heat from seemingly cold air and move it into your home so you can be comfy. In the summer they “switch gears” to become air conditioners. These systems can be ducted like most US houses or can be “mini-split” system which are popular in throughout Europe and Asia.

The beauty of heat pumps is that they can run on electricity from solar panels or wind power, biofuels, hydropower or batteries. They don’t require any carbon, fossil fuel energy. They are a proven technology, used world-wide. You can make the switch and be part of the global climate change solution.

Heat pumps along with air sealing, high levels of insulation and ventilation can make your house both highly comfortable with great air quality while enjoying low energy bills. You can be solving the global climate change problem from the comfort of your home.

Give BECT a call, we can help you get off of carbon energy and be part of the solution.

Which air filter should I be using in my home's furnace/Air Con system? 9/8/18

I want to get the smoke out of the air where my children live. I want lower energy bills.

This is the question for health and measured performance. What difference does it make? Apparently, having a lower pressure drop across the air filter yields more airflow and less wattage used by the motor, (hopefully a permanent magnet, electronically cummutated motor of the right size.)

At BECT, designing duct systems, the most challenging data to find is the pressure drop across filters, “Y”s, evaporator coils, register boots, start collars, ducts, plenums and grills. Once we have all that data we input it to Wrightsoft software and we can prove/know/model the performance of the airflow. Without all those we are making educated guesses, hopefully correct.

Many of the components of a duct system are difficult to find pressure drop numbers for. Knowing that, we can eliminate variables and work with what we know to be true by specifying low pressure drop components. Oversized evaporator coils, up-sized return ducts and proven air filters matched to filter boxes with lo-resistance grills fit that bill.

Below is a note from 3M to a user about their filters and how much other manufacturers’ filters rate RE: MERV and pressure drop in inches of water column. This is critical data when designing a high performance duct system.

SUMMARY: The Ultra Allergen 1500MPR (for 1 inch depth HVAC) is the LOWEST pressure at 0.15 (vs .20 for the MPR 600). So it didn’t make sense for me to go for MPR 300, MPR 600 or MPR 1000.

The complete response from 3M below:

Generally speaking, for most residential HVAC systems, the filter will become restrictive when it reaches a .5 pressure drop.

All of our filter media fibers are polypropylene and polyolefin plastic which will remove particles that measure 3 to 10 microns.

Microparticle Performance Rating (MPR), MERV Ratings, and pressure drops are as follows:

Elite Extra 2400

3-10 microns – 96%


pressure drop .21

Elite Allergen 2200

3-10 microns – 94%


pressure drop .18

Maximum/Ultimate Allergen 1900

3-10 microns – 93%


pressure drop .16

Allergen Deep Pleat 1550 (4″).

3-10 microns 97%


pressure drop .12

Ultra Allergen 1500

310 microns – 90%


pressure drop .15

Odor Reduction 1200

3-10 microns – 85%


pressure drop .24

Micro Allergen 1000

3-10 microns – 80%


pressure drop .21

Dust & Pollen 600

3-10 microns – 65%


pressure drop .20

Dust Reduction 300

3-10 microns -35%


pressure drop .20

Flat Panel

3-10 microns -5%


Pressure Drop .08

Pressure drop is a measure of air flow resistance. It is measured by inches of Water Column (W.C.) at 300 feet per minute (FPM).

Clean/new filters are not restrictive to air flow. Filters will become restrictive if they are not changed when needed. A filter’s life is actually determined by the user’s living conditions and will vary for every user. Generally speaking, we recommend changing filters approximately every 3 mo nths.

To determine when the filter needs to be change, we suggest holding it up to the light. When you cannot see light through the filter, it is ready to be changed, even if it is before 3 months.

If you are concerned about airflow, you might want to use the filter with a lower pressure drop.

If you have a high velocity furnace with high fan speed, you may need to change the filters more frequently, every 1.5 to 2 months.”

Compare the above when choosing filters. Doing so could be the difference between staying below .58 watts/CFM when doing Fan Watt Draw HERS tests. First you need the airflow to pass Total Airflow HERS test, then you need low watts from the motor to pass Fan/Watt Draw.

Register Sealing Before Having BECT Do A Duct Leakage Test 8/10/2018


Please make sure that the registers are sealed as in the photo below, before BECT comes to test the system for duct leakage.

Seal the register boxes to drywall or hardwood floor with UL 181 aluminum tape as shown below.

pic 1

Aluminum Tape (must be UL 181)      

pic 2

 Register sealed to drywall with Al tape.


The photos below are examples of what the registers/returns should not look like

pic 3

Unsealed boot in drywall, on ceiling. This won’t hold air.

pic 4

Unsealed 1950s boot in hardwood floor, unsealed.

pic 5

1920s register boot, unsealed to plaster yet painted black.

Also, please make sure that your forced air unit set on the highest speed so that you can achieve 350 cfm/ton​ for the 1. Total Airflow Test and 2. The Fan/Watt Draw Test.

Also, don’t forget to drill a 1/4 inch hole in each side of the plenum (both supply plenum and return plenum) and mark the hole, HSSP, for Hole for Static Pressure Probe. Put aluminum tape over the hole but make sure marking is visible for HERS test. If those access holes are not there – you’ll need to do it at the test. They are so that someone can insert a probe on each side and see the difference in temperature and humidity changes before and after the air moves through the evaporator coil.

If you have any questions on how to seal it, we also have a video on our website detailing how to properly seal your ducts. Click this link here to watch the video, http://bect.us/videos/. You can also watch our other videos on energy efficiency in the home on BECT’s YouTube channel. Check it out here, https://www.youtube.com/channel/UCAd8LCb6fzHAkzqOu9loGrQ/videos?view_as=subscriber.

Stay cool and comfortable,


Dear CEC, Please Approve Wrightsoft Software For Alterations And Additions Compliance, (Title 24 Performance) 8/10/2018

Dear Commissioner McAllister,

I am writing to request that you to approve Wrightsoft software to perform title 24 energy compliance (performance) for residential alterations and additions in California.

I am told that the software is now able to perform compliance for new homes but not for alterations and additions, the far more common jobs found here in the San Francisco Bay Area.

I have been using Wrightsoft for the last year and am extremely impressed with it as a tool to perform load calculations, duct design and equipment selection. As a HERS rater I see failure to perform to code every day in the HVAC systems I test, with about 75% of them fail to move enough air in AC mode. Having HVAC systems be designed properly yields systems that perform to those design standards.

I understand that the CEC is now evaluating Wrightsoft. If that is so, I ask you to accelerate the evaluation and allow Wrightsoft to be used in title 24 compliance in alterations and additions.

It is my understanding that 1% of California residential HVAC changeouts get load calculations done. This must be why I see such wildly oversized air conditioning systems in my testing.

Here is what I’d like you to do to improve energy efficiency and efficacy in new/alterations in California,

  1. Allow Wrightsoft to be used for T24 compliance in Alterations and additions.
  2. Compel the Contractors State License Board to teach HVAC contractors to use load calculation software and that calculations, design and equipment selection is code required.
  3. Sponsor classes to teach HVAC contractors how to use load calculation/duct design software.
  4. Encourage title 24 consultants to use load calculation software and do both compliance and design.

Doing only compliance misses the greater point of creating heating/cooling/ventilation systems tailored to a particular house and actually achieving efficiency and performance. I see “T24 compliant” houses fail HERS tests every day.

If you need any help, please do not hesitate to call me.

Thanks for your help in creating an energy efficient economy in California.

Very truly yours,

George Matthews

Building Energy Compliance Testing www.bect.us Phone 510 520 4443

Walnut Creek, CA 94597

``Like Italy in the 1960s`` 10/31/2017

A lovely guest house in the country. Brand new, white, gleaming and beautiful. The owner is British. I tested the performance of her new HVAC system. It failed three HERS tests.

I explained to her each of the tests and why the system failed. The ducts leaked too much air. The system did not move enough air for the size of the air conditioner. Why? The return ducts are either too few or too small. The MERV 8 filter installed is restricting air flow so it should be bigger or perhaps there should be two of them. The 2017, airtight, well insulated 1500 square foot house with low e, argon dual pane windows doesn’t take much to heat or cool. How did it end up with a 3 ton AC and restricted, leaky ducts?

The homeowner told me that it was “like Italy in the 1960s.” A top-heavy bureaucracy well insulated from those doing the actual work or needing to get things done. The individual people are often brilliant, but people are not working together. Some were also incompetent.

We have a real problem in the SF Bay area with HVAC contractors installing air conditioning systems without following the CA energy code’s “Mandatory Measures”, nor CalGreen. Every day I test new systems that have not been sized and designed as per code requirements. This yields systems that use more energy and provide less comfort. This has a real effect on energy use in the SF Bay Area. These improperly designed system can last 30 years or more and will waste energy daily ’til near 2050 when they will fail.

California Title 24 Energy experts say that 1% of residential HVAC systems are properly calculated for sizing and have their ducts designed per the specs in Title 24. Only 10% get permitted and tested.

Of course, the Energy Commission did not make up these design specs. They use the Air Conditioner Contractor’s of America Manual J, Manual D and Manual S sizing, duct and register grill design specifications.

Sadly, there is no continuing education from the Contractors State License Board for HVAC contractors. Hence, they have no idea of what is in the California Energy Code or how to build comfort system that conform to it.

We are now in the 2016 energy code. Builders and HVAC contractors are nowhere near understanding what is in the current code or how to meet it. At the same time we are nearly 2 years away from the 2020 energy code when new buildings will be “Zero Net Energy”, meaning that houses will generate as much energy in a year as they use in a year. We have a lot of work to do to educate the building industry workforce in order to get up to speed with upcoming code changes.

Let’s fix this problem.  Just like engineers design our building so they stand up to earthquakes via code required structural design, let’s have our HVAC systems engineered per our energy code. We need to require building department design review first, before permitting these long lasting, energy using systems to get built.

CSLB and California local Building Departments, please get up to speed educating the building industry workforce and enforcing the energy code.

George Matthews, owner
Building Energy Compliance Testing
Serving the San Francisco Bay Area

How to Improve California's Energy Code 10/11/2017

Actually enforce it. 


We are only enforcing part of California’s science and engineering based set of rules about how we use energy in buildings.  


In our state, before we build buildings, the plans must pass a set of rules that state what must be done to pass code. 


CAL Green and the HVAC requirements clearly state these requirements. However, while the plans all pass energy code on paper, once in the field 99% of what happens is that HVAC systems are not sized, selected according to national engineering societies standards that have been recommended for half a century. 


Instead of using standard, accepted engineering software to size and select the furnaces and air conditioners, contractors size according to crude rules of thumb more appropriate in the Nixon administration.  



I was just in a custom house 30 minutes from Silicon Valley. It was 3500 square feet, beautiful and perfect. However, the HVAC contractor sized the air conditioning systems (two) to 375 square feet of house to a ton of air conditioning. This house has two four ton air conditioners. It also did not have enough airflow to satisfy either system. The contractor got the sizing wrong because he guessed at the duct and return sizes. The house is done and ready to sell but he now must cut more holes in the ceiling and install new cold air returns. There was not a speck of dust in this house and now it is time for little remodel of the dining rooms ceiling with all the dust it entails. 


This goes on every day. California energy specialists state that about 1% of CA house have their ducts, furnaces and air conditioners designed in approved software. Energy experts I ask say about 5 percent of CA systems get HERS tested.  


How to fix the problem. Enforce the CA energy code HVAC Mandatory Measures and CAL Green Requirements. It is so easy. Just like one submits drawings or engineering to building departments to prove that houses will stay standing in an earthquake, contractors will submit the plans for the equipment they install. 


The state provides free classes on how to use such software. However, the state should offer  


Here is how the improvement to many AC system 30 years old. These are long lasting systems. In consequence to their substandard design considerable energy is wasted. Properly sizing duct systems reduce callbacks to fix bad work like the contractor above. 


Guessed together systems also provide un-comfort and stop air filtration from happening properly. 


The great benefit of following the code is that HVAC systems then actually pass the HERS tests that are required. No trial and error remodels on brand new systems.  


California Building officials, what would it take to get you to require that HVAC contractors submit an approved plan generated from an approved method. Someone has to come up with the plans, otherwise the result is brand new air conditioning system failing energy performance tests. 


I know that if I had the power and the resources, I’d tell every building owner investing in new equipment/systems, general contractors responsible for their subs installing expensive capital equipment and the HVAC installers that they must produce a design before installation. 


This will guarantee that systems perform properly, and building owners and residents, perhaps you and your family get the comfort you have paid for. 

Letter To The California Energy Commission 5/19/17

Dear California Energy Commission, 

I’d like to let you know about some failures in the energy code system as I see it in the field as a HERS rater testing alterations of existing houses and new houses. 

I work from Silicon Valley to the Wine Country, up and down the Peninsula and in the East Bay Area. I am usually in two or three houses per day. I’ve owned Building Energy Compliance Testing, www.bect.us since June 2014. 

What I see is that the only time a house gets HERS tested is when it is new construction, there is an addition or major remodel and it includes a new furnace and ducts. If a homeowner just gets a new HVAC system, it rarely gets permitted and tested. I’ve spoken to other HERS raters and energy consultants, we all suspect that only about 5% of new or altered HVAC systems in California get HERS tested. 

Every time I go to a job and meet an HVAC contractor I ask them how they sized this system. They almost always answer, “Square feet.” When I dig deeper into it, they often tell me that the rule is 500 square feet per ton of air conditioning.  Often times, they tell me that the guy at the supply house told them what size to buy. I tell them that the state of California requires ACCA Manual J, D and S calculations. I have one client who I know uses Wrightsoft calcs on every job. 

This lack of design before construction causes real problems. I often see 5 ton AC systems on smaller houses in fog banks. Contractors usually fail airflow tests because they wildly undersize cold air returns. This makes the testing process a burden to both the homeowner who can’t get the job “finalled” and has to pay for multiple HERS tests. These big AC systems contribute to peak electric loads, uncomfortable houses and high energy bills. 

The problem is with the building department when a job is permitted. When one submits plans for an addition or new construction job to a building department they require structural engineering. What they don’t do is require the engineering on the HVAC system even though the builder or owner signs off on Calgreen and the T24 report and mandatory measures.  Calgreen includes 4.507.2, stating that heating and AC systems shall be sized, designed using ACCA Manual J, D and S. 

There is a real disconnect here that needs to be addressed by the CEC, Building Departments and the Contractors State License Board. I’d like to get the heads of these departments in a conference room and have them figure out a way to get energy code compliance above 5% and closer to the majority of jobs. 

While I love the fact that the CEC is taking us to Zero Net Energy buildings by 2020, I find it absurd that 95% of current HVAC jobs are not achieving the 2016, 2013 or any other year of the code. HVAC contractors could be the champions of building an energy efficient economy in California. However, what I see is that the vast majority of them are actually outlaws or skofflaws, ignoring codes and evading local building authorities. 

Aside from energy codes, these contractors are making electrical and gas connections as well as installing flues to hopefully rid houses of poisonous combustion gasses. These three things are all able to kill people and deserve to have another set of eyes on them. Deaths from carbon monoxide are not a rare occurrence. 

While I am on the job inspecting and testing HVAC systems I look at the insulation installation. Generally, attics are poorly insulated and general & roofing contractors do not use radiant barriers. When this bad combo exists in the attic, homeowners buy air conditioning systems, (even in the foggy Bay Area). We in the energy efficiency industry should be helping building owners install these systems so as not to need compressor cooling and the energy it takes in late in the afternoon at peak load. 

Attic hatches are not sealed or insulated in most Bay Area houses. In about the last 90 attics I’ve climbed into, I’ve found 3 that actually have attic hatches that are air sealed and insulated. Insulation contractors just don’t do this. I suspect that since there is no HERS attic hatch inspection no one else cares. In my experience, City building inspectors pass any insulation installation no matter how poorly installed or how many gaps there are around boxes or can lights. Q: When is an R-39 attic actually an R-33.85 attic? A: When the attic hatch is unsealed and uninsulated. 

Here is what I’d like to see, 

  • Get the majority of HVAC contractors to have their work inspected and HERS tested. 
  • Make contractors responsible for 4.507.2, sizing HVAC systems before they build them. 
  • Have insulation installations inspected and enforce proper installation. 
  • Have attic hatches inspected for air sealing and insulation. 
  • Require HVAC contractors get continuing education in the energy code. 

I know this is a lot to ask but I request that you coordinate and work with other state agencies like the CSLB and organizations of local building officials to actually enforce the California building energy code. If there is anything I can do to make this a reality, please let me know. 

Failed HERS Test and Final Inspection - How to Avoid the Pain and Expense and a Solution to the Problem 5/4/17

It happened again, yesterday, doing a HERS test on a new house, HERS testing the air conditioning system.

This was the third time I was at this house testing. The technician, not an HVAC contractor but a tech hired by the owner, had added another duct to coax the 5 ton air conditioner into blowing 1750 cubic feet of air per minute, the minimum required by code.

The system did not perform to code. It moved 1600 CFM but not the 1750 required by the State of California. We looked at his work. He’d added a shiny silver drooping limp flex duct connected to a small return filter box. He told me there was nothing more he could do. I suggested pulling it taught in a straight line to the return. He didn’t think that would work. He really did not like my alt suggestion of a straight metal duct to reduce air friction.

I exited the front door with him. He threw is boots hard at the driveway and cursed in anger. I could sense deep frustration and a man who probably won’t get paid until the job passes. I felt sorry for him. He did not know that these systems are supposed to be sized according to manual J, Manual D and Manual S in software such as Wrightsoft. The owner or builder had signed off on building to the Calgreen checklist which states that the HVAC system will be sized according to Manual J, D and S. Apparently, no one took that seriously. The City of Orinda building department never asked for this basic engineering. Hence, it never got done.

The technician had guessed the system together. The 2600 square foot house in mild, often foggy Orinda, California somehow received a 5 ton air conditioner, the largest available. When it failed he asked me what to do. I had to tell him that I am not the designer but the State’s Energy Commission does have something called the Building HVAC Requirements.  http://www.energy.ca.gov/2013publications/CEC-400-2013-001/chapters/04_Building_HVAC_Requirements.pdf

In these Building HVAC Requirements, under table 4-11 (Standards Table 150-D): Return Duct Sizing for Multiple Return Duct Systems, there is a line that shows a 5 ton air conditioning duct system having two 20 inch return ducts with a minimum gross filter grill face area of 1500 square inches.

The system I was testing did not have anywhere near 1500 square inches of filter grill face. It had two filters equaling 768 square inches, about half what code is requiring.

If this system had actually been designed rather than guessed together by a person using some “rules of thumb”, it most probably would have passed the first time. The problem is that this is the 3rd time I’ve seen this in a ten days. It happens all the time in the affluent, well educated San Francisco bay area, home to so much energy efficiency research and development.

I usually ask air conditioner contractors how they sized the system I’m about to test. Almost invariably they tell me they use the “square footage rule”. “What is that?” I ask. They then explain that for every 500 square feet of house they put in a ton of AC. Easy! 2500 square feet of house equals 5 tons of AC. System sizing complete! Sometimes they admit that the guy at the supply house told them what size was needed.

We know the problem. HVAC contractors and unlicensed technicians who install HVAC systems don’t size those systems according to protocol of the Air Conditioning Contractors of America. The results are brand new, shiny yet poorly operating systems that will waste energy and perform poorly for decades to come.

Here’s the solution. City Building Departments must get manual J, D and S designs before contractors can build that system. Just as seismic engineering is required for buildings before they are built, so to can we require that mechanical systems be engineered before they are built. Then we just have to work with the problem that the residential HVAC industry evades building departments permits and code HERS testing some 90% of the time.