Better Than Code - A Platform That Helps Builders

Currently in Ontario, which has performance based code, (Supplementary Bulletin SB-12) there are 13 prescriptive paths that a builder can choose from when applying for a building permit (see table below). Packages A – M have different combinations and when modelled using HOT 2000 on a reference house all packages come out to an EnerGuide 80, which is the minimum energy performance rating for a new home built in Ontario since 2012. In some municipalities, subdivision approvals and building permits are awarded based on something better than code, and until recently typically Energy Star or EnerGuide were the only options on the menu. Energy Star, which started out as a builder friendly program has had great success in Ontario, but having gone through multiple revisions, now on it's 6 version, there are significant challenges with v12.3. The biggest, if a builder does not pass an air tightness test (2.5 ACH @ 50 pascals on singles and 3.0 for semi detached and town houses), it is not eligible for certification.* Builders would now be in breach of their contract, and often occupancy and closing is contingent of certification. Mandating a program that has such rigid guidelines has significant liabilities for a builder.

* A house cannot fail on an air test and pass using the performance path under this revision*


** PACKAGE "J" - BUILDERS CHOICE – LOW COST - R22 main walls, R12 Basement Blanket

Better Than Code is a platform that works for both municipalities and builders. Using the HERS® Index, which calculates overall energy consumption using REM/Rate software, which is recognized in the Ontario Building Code, whole house energy consumption is measured. There is no pass or fail on air tightness, and HERS® accounts for plug loads, air conditioning and rewards renewables like drain water heat recovery and solar.

There is a code change coming in 2017, and although the Ministry of Housing has not confirmed what the new prescriptive paths will entail, notionally it will be 15% better than the current OBC and it is likely that it will take shape similar to the proposed table below.

Our approach is to help builders prepare for the upcoming code change now. The 'sweet spot' is 15% and we are able to help builders navigate the complicated performance path plugging in different options to determine the best way to get to that threshold. Whether it's a more efficient hot water tank, a better ERV, BTC lets the builder decide how to showcase the energy consumption improvement. The chart below shows generally how to get to 15% better when comparing to Package J.

The HERS® Index - What Is It and How Does It Work?

The HERS® (Home Energy Rating System) Index measures a home's energy efficiency and there are a lot of great reasons to have a home energy rating performed on your house.

It can tell you so much about the home you live in, like how efficiently it's operating and where you can make modifications for greater energy savings. When you're selling your home, a low HERS® Index Score can command a higher resale price. And when you're buying a home you can anticipate the costs of energy bills and efficiency upgrades.

How does the HERS® Index work?

A certified Home Energy Rater assesses the energy efficiency of a home, assigning it a relative performance score. The lower the number, the more energy efficient the home.

The U.S. Department of Energy has determined that a typical resale home scores 130 on the HERS® Index while a standard new home is awarded a rating of 100.

  • A home with a HERS® Index Score of 70 is 30% more energy efficient than a standard new home
  • A home with a HERS® Index Score of 130 is 30% less energy efficient than a standard new home

More on what the scores mean.

HERS® measures whole house energy consumption, which is unique to this platform. It accounts for plug loads like air conditioning and recognizes renewables like solar photovoltaic and drain water heat recovery (DWHR). Unlike other recognized energy labels (i.e. EnerGuide or ENERGY STAR®) which use HOT 2000 software, HERS® assesses improved energy performance based on a comparison of a home as it was constructed ("as-built") to a benchmark model of the same home constructed to the minimum building code requirements (i.e. not including any energy efficiency upgrades that were implemented). For other energy rating labels, a single standard benchmark or reference home is typically used despite variability in house types and sizes. As such, the HERS® approach allows for a true home energy comparison.

Some of the variables included in an energy rating are:

  • All exterior walls (both above and below grade)
  • Floors over unconditioned spaces (like garages or cellars)
  • Ceilings and roofs
  • Attics, foundations and crawlspaces
  • Windows and doors, vents and ductwork
  • HVAC systems, water heating system, and your thermostat

HERS® Software is Recognized in the Ontario Build Code

HERS® Software is referenced in SB 12 OBC -A- Application of Performance Compliance Path

For the purpose of calculating the annual energy use of a proposed design and a design based on a selected compliance package, the following software may be used:

RESNET accredited Home Energy Rating System (HERS) software, such as:

  • OptiMiser, EnergyGauge, EnergyInsights, REM/Rate

Guidelines for HERS® Raters:

  • Follows RESNET Standards for technical and administrative requirements
  • CRESNET (Canadian Residential Energy Services Network) and RESNET are the governing body
  • HERS® is an ANSI Standard
  • HERS® Raters are trained and certified following RESNET Standards
  • HERS® measures whole house consumption and is the most recognized energy scale in North America (over 1 million new homes in the U.S. HERS Rated)

In Ontario for the most part code is a HERS® 60. The 2009 OBC, a new home was a HERS® 70. An existing home in Canada built before 1990 is typically a HERS® 110?

On a new home an important part of the HERS® Rating is there are 2 on site inspections, one is voluntary the second is mandatory.

Inspection 1

The first inspection happens before drywall. The thermal by-pass inspection grades for the quality of insulation. This is an important procedure, as an effective R–value (the resistance to heat flow) is related to how the insulation is installed which directly relates to its thermal performance. During this inspection the energy rater is looking for voids and compression in the wall cavity, and is also looking for any holes or penetrations that will affect the air tightness of the home. The grading of the insulation is incorporated in into the energy model and adheres to the RESNET (Residential Energy Services Network) industry standards. Determining the insulation values is explained below.

A better installation results in a better overall energy performance. By grading the insulation we can show an effective R-value and quantify that into energy savings.

Inspection 2

Measuring the air tightness, confirming all of the mechanicals and verifying builder specifications is typically done a couple of weeks prior to occupancy. The CGSB 149.1 Standard for blower door testing is used to measure air tightness. When all of on testing and verification is completed the results are inputted into the REM/Rate software which calculates the homes overall energy consumption and HERS® Score.

Helping Builders Sell Energy Efficiency

Energy Star has done a great job in marketing energy performance; it is a successful brand, yet for a builder it provides little other than the basic assumption that an Energy Star home is better than one that isn't. The program has gone through 4 major revisions, which has caused confusion in the market place. The most significant change is the requirement for air tightness, if you fail the air test you cannot certify which is a liability for a builder and occupancy and closing can be tied to certification.

With the HERS® Index, which measures whole house energy consumption it allows a builder flexibility, not only can they showcase an incremental % increase in performance based on inputs, it allows those improvements to be equated into annual consumption levels based on the energy source and what the annual operating costs will be. Builders can now articulate the value of more insulation, and higher SEER air conditioning or higher efficiency ventilation systems, and then can charge for those upgrades, as it's an easier sell when a homeowner understands how it will impact their annual operating costs.

Our services include helping a builder determine their standard package (i.e. 15% BTC) and customizing different upgrade options, whether it be 15-25% BTC, and we help sell that for the builder. The most successful way is to get as many of the buyers in one room and explain the value of the solutions, both from an environmental angle and financial. Typically we have a 30% uptake, and whether it's improved ventilation systems, better basements or exterior insulated sheathing we are able to help sell the energy efficient features, which historically loose out the decor centre items like granite countertops. Think of the HERS® Index as an MPG (miles per gallon), it is a measureable and marketable tool that allows a builders homeowner to have both the granite countertop and sustainable upgrades, because the money they will save in the long run with the efficient upgrades will more than pay for the fancy island countertop.

Educating Municipalities about an Alternative Path

Municipal planners and building departments are the gate keepers when it comes to subdivision approvals and building permits. In order to secure approvals builders must meet certain sustainable checklists or green initiatives is part of the process. It often varies from municipality to municipality. Commonly Energy Star or EnerGuide, sometimes even LEED are referenced as a requirement for subdivision approvals. Until recently there has not been an alternative to these programs. Because the HERS® Index software is recognized in OBC SB-12 there is another way of showcasing energy performance which can meet municipal requirements.

Using HERS® is actually a simpler and more effective tool for energy performance and it provides the builder with more flexibility. For example if a builder decided to sell a home with a 15 SEER air conditioner, under Energy Star there is no credit for that, as the software used for energy modelling does not recognize plug loads. Now the biggest deal beaker for builders with Energy Star is the air tightness test, it is a pass or fail. For singles the air test must measure 2.5 ACH @ 50 pascals and a NLR (normalized leakage ratio of .18). So what happens if the result is 2.6 ACH @ 50 pascals and a NLR of .19? It can't be certified as an Energy Star home, does that mean the builder can't close the house because the builder has not satisfied the requirements of the municipality?

When using HERS® that result is simply put into the software and modelled and depending on the result it may or may not affect the overall consumption level. Energy Star is notionally 20% better than code, so using HERS® municipalities can still require homes that exceed the building code, but they could allow builders choice and not sole source government programs. Using a better than code approach is more flexible, as it's not dictated by a 20% jump every code change, (i.e. Energy Star). Limiting it to a % better than code is much more sustainable, and this is a platform that works for both the municipality and builder.