As I review the various programs designed to provide high performance homes to our clients I find that most programs are prescriptive in nature and are designed with the new home builder in mind. They enable the builder to achieve some sort of certification for the home if it meets certain requirements. This is an excellent approach for new home construction but what about the existing stock of homes. According to the U. S. Census Bureau there are 124 million homes today. It has been estimated that 60% of today’s homes will be present in 2050. Today’s homes account for 21% of the energy consumed annually in the US. By contrast US automobiles account for 20%.
Consider the cost of energy to run a house. The average energy cost bill for an American home was $1,680 per house or $191 billion annually. The cost of natural gas, electricity, and fuel oil will only continue to rise. In order to make the best use of their remodeling dollars home owners will start seeking ways to roll energy saving options into their remodeling projects. The big question for remodelers will be how to 1) evaluate the requirements of the home. 2) accurately estimate the upgrades in addition to the requested remodeling project, and 3) verify that the home performs as predicted.
Home performance contracting requires that the practitioners understand how the house works as a system, and how the many components are interrelated and interact with each other. Before design of a project begins, the current structure is evaluated for air tightness of the building envelope, quality of windows, adequacy of insulation, presence of roofing failures, and efficiency of the heating and cooling systems. This evaluation will require some measure of testing by way of a “Blower Door” and “Duct Plaster”.
If you are currently not equipped to conduct these evaluations you may contract this test out to a local home rater for a nominal charge. Once the results are in hand you are prepared to start designing your projects with home performance in mind.
The Elements of Home Performance Remodeling
What is it that you will be doing that is different from a business as usual remodeling project? The following list outlines those tasks that must be done to address energy and comfort issues in most homes today:
- A safety and efficiency check of the heating, cooling and hot water equipment including testing for carbon monoxide and backdrafting of combustion appliances
- Cleaning and tune-up on combustion equipment
- Testing of building air leakage rates using a “blower door” and developing strategies to improve performance
- Identifying air and duct leakage sites and connections between building components using a digital manometer
- Verifying existing insulation levels
- Insulating and air sealing the building envelope
- Testing of duct leakage rates and how the duct system interacts with the building
- Sealing duct leaks and balancing distribution system
- Testing of humidity levels
- Identifying moisture sources and damage
- Fixing leaks and flaws in building envelope
- Providing proper drainage for the foundation
Walt Harwood, head of Neil Kelly’s Handyman and Home Performance divisions points out that the major challenge to the average Remodeler is cost of entry. He says “the tools required to conduct the tests and analysis can be quite expensive.”
he tools required to conduct the pre and post tests include as a minimum a Blower Door, Duct Blaster, CO monitor, and a thermal camera. In addition to the required equipment, there will be the cost of training and certification. Rather than go through the initial expense, remodelers can hire subcontractors to conduct the testing and analysis then the remodeler can implement the require corrective actions in conjunction with the remodeling project.