Green Home Building Science

Green Building Science

Certified High Performance (CHiP)

Epic Homes sets a new industry standard on each home we build. Every home built includes Certification in the Certified High Performance (CHiP) home program. in addition, it is then inspected, tested, and scored by an independent third party Certified Energy Rater that works for the homeowner. Our homes are constructed virtually in the the planning stages to predict performance before any construction takes place on the property. To ensure our predictions are met, each home is inspected by the Rater during various stages of construction and finally test to confirm it’s performance. Test scores are recorded and all homeowners are provided with results and HERS score. You can build an efficient home at an affordable price. Let us show you how!

The Science Behind Green Building

Sustainable building takes most of us back to the classroom for a refresher on the physical properties of energy, air, and water. Green building practices, as well the selection of the appropriate building materials, revolve around a few basic principles of science. Science is what sustainable building relies on, principles that once understood can guide you every step of the way, including:

– A house is a system of interrelated parts

– Energy loses some of its potential each time it is converted from one form to another, which explains why passive solar heat is much more efficient than electric heat

– Form follows function when it comes to design, meaning that construction should be tailored to the environment in which the house is built.

– Air leaks in the building envelope represent a significant loss of energy and open the door to moisture damage inside wall and ceiling cavities.

– Controlling the movement of heat, air, and moisture involves every part of the building and everyone on the building team

What Is The Certified Home High Performance Home Program?

Certified High Performance Home is the program of the Local High Performance Building Council (HBPC) of Greater Columbia. One of the primary duties of the HBPC is to administer and update the program for members. The program is based on the National Green Building StandardTM

If you’re looking to have your next home built to a higher-performing standard, you’re in the right place.

Through the Certified High Performance Home program, the house is certified green, not the builder. Our program is based on the ANSI-approved National Green Building StandardTM which gives you, the homeowner, and the builder many options on achieving certification. All homes must be third-party tested in order to be certified in the program and therefore must reach a minimum standard in the program. After that, you can make the home as green as you like.

Consensus as to what is “Green” or green enough isn’t universal. In reality, green building is driven by science not ideology and must result in the construction and reconstruction of our built environment in harmony with the planet’s ecosystems such that we live within the limitations of those natural resources and pass on sufficient resources to future generations. Driven to the absolute by science, the language above would change from “design and construction of homes and communities with some or all of the following characteristics” to “design and construction of homes and communities with all of the following characteristics.” While all the tools and techniques needed to do this exist today, a huge educational challenge must be met to get these tools and techniques into use to accomplish this reconfiguration and reinvestment in our built environment.

Studies show great interest in green building but significant confusion as to what it entails. In too many cases this confusion and accompanying assumptions that green building requires all of the characteristics described previously (and is thus too expensive), actually impede adoption and incorporation of important and feasible advancements toward sustainability.

Debates exist as to whether to label only homes and buildings green when they include all of the previously described characteristics or whether we will move our society farther, faster through applying this label to homes, including some or most of the green building characteristics above.

What Is An Independent Third Party Energy Rater?

A certified home energy rater must successfully complete training by a RESNET Accredited Rater Training Provider and must be certified by a RESNET Accredited Rating Provider. A rater must successfully complete training by a RESNET accredited rater training organization. The training is conducted in accordance with a syllabus developed by RESNET. Each candidate rater must perform two ratings, including software operations, in the presence of trainers.

Certified Raters must also pass examinations that demonstrate a practical, working ability to effectively use the knowledge and skills set contained in Section 5.3 of Chapter Two of the national home energy rating standard to produce accurate and fair Home Energy Ratings. This examination may either follow training or it may be taken as a challenge examination.

The training addresses:

– Basic principles of building science (i.e., viewing the home as a system)

– Thermal resistance of insulation materials

– The minimum rated features for buildings

– Blower door testing procedures

– Duct leakage testing procedures

– Variations in construction types and their ramifications

– Types and efficiencies of windows


What Is a HERS score?

The Home Energy Rating System (HERS) Index is the industry standard by which a home’s energy efficiency is measured. It’s also the nationally recognized system for inspecting and calculating a home’s energy performance.

What Does a HERS Index say about a house?
The HERS Index is a measurement of a home’s energy efficiency and there are a lot of great reasons why you should have a home energy rating performed on your house.

A HERS Index Score can tell you so much about a home you are thinking of buying. Heating, cooling and water heating constitute the largest cost of homeownership outside of the mortgage loan. The HERS Index Score will tell you how well the home performs energy-wise. The HERS Report will outline the energy features of the home and the expected cost of utility bills.

It will also provide you with invaluable information about the existing 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 HERS Index 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 home built to the 2004 International Energy Conservation Code is awarded a rating of 100.

To calculate a home’s HERS Index Score, a certified HERS Rater does an energy rating on your home and compares the data against a ‘reference home’– a designed-model home of the same size and shape as the actual home, so your score is always relative to the size, shape and type of house you live in.

Some 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 system, water heating system, and your thermostat.

– Air leakage of the home

– Leakage in the heating and cooling distribution system


What Is a Certified Green Professional?

The Certified Green Professional™ designation recognizes builders, remodelers and other industry professionals who incorporate green and sustainable building principles into homes – without driving up the cost of construction. The required courses provide a solid background in green building methods, as well as the tools to reach consumers, from the organization leading the charge to provide market-driven green building solutions to the home building industry.

CGP coursework is closely aligned with the ICC 700 National Green Building Standard, which includes chapters on energy, water and resource efficiency, indoor environmental quality, lot and site development and home owner education and is the core curriculum for the required CGP classes.

What Is Duct Blast Testing?

Two different types of performance testing systems are used to measure duct leakage: a duct blaster test or a pressure pan test.

A duct blaster combines a small fan and a pressure gauge to pressurize a home’s duct system and accurately measure air leakage of the ductwork. This test is similar to a pressure test of a plumbing system. Duct leakage can increase heating and cooling costs over 30% and contribute to comfort, health and safety problems. Here is how the test works:

A duct blaster is used to directly pressure test the duct system for air leaks, much the same way a plumber pressure tests water pipes for leaks.

The duct blaster fan is first connected to the duct system at the air handler cabinet, or a return grille. After temporarily sealing all remaining registers and grills, the duct blaster fan is turned on to force air through all holes and cracks in the ductwork.

The fan speed is increased until a standard test pressure is achieved in the duct system. A precise leakage measurement is then made using an airflow and pressure gauge connected to the duct blaster system.

What Is Blower Door Testing?

The blower door fan is used to blow air into or out of the building, creating either a positive or negative pressure differential between inside and outside. This pressure difference forces air through all holes and penetrations in the building enclosure. The tighter the building (e.g. fewer holes), the less air is needed from the blower door fan to create a change in building pressure. Typically, only depressurization testing is performed, but both depressurization and pressurization are preferable. Different values for blower door metrics are to be expected for pressurizing and depressurizing, due to the building envelope’s response to directional airflow. The smallest fan ring that allows the fan to reach the maximum target indoor/outdoor pressure differential should be used. A multipoint test can be performed either manually or using data acquisition and fan control software products. The manual test consists of adjusting the fan to maintain a series of indoor/outdoor pressure differentials and recording the resulting average fan and indoor/outdoor pressures. Alternatively, a single-point test can be performed, where the blower door fan is ramped up to a reference indoor/outdoor pressure differential and the fan pressure is recorded. Often the blower door hardware converts fan pressure measurements directly to fan airflow values.