How to super insulate your home even during heat pump usage-news-317

Most energy-conscious people know that when it comes to home insulation, more is better. But homeowner Alex Cheimets is literally thinking outside the box with his “superinsulation” plan.

Rather than just blow in a few more inches of standard cellulose insulation in his attic, Cheimets is in the throes of an ambitious project to seal the outside of his home with two layers of insulating foam board.

Known in building industry as a superinsulated home, the foam blanket will keep hot (and cool) air in, and also block the cracks that let in outside air. If all goes as hoped, he will cut oil consumption by 70 percent at his 80-year-old, two-family home in Arlington, Mass.

A superinsulated home has foam insulation placed on the outside of the walls and ontop of the existing roof.

For Cheimets, superinsulation has become a bit of a hobby, one that’s been frustrating at times. He set off two years ago with good intentions–conserving energy for the benefit of his pocketbook and the environment. But like a cutting-edge user of new technology, he has had to overcome a number of unexpected hurdles, notably a lack of basic information and experienced contractors.

Luckily, Cheimets is persistent, organized, and, he admits, “a little obsessed.”

Earlier this fall, contractors began work on the job, which is expected to be finished early next year. Along the way, it’s become a pilot project that some hope will become a model for dramatically lowering energy consumption in the millions of existing homes.

Leading-edge green
Being a guinea pig for superlinsulated homes has paid off in some ways even before the home’s co-owners receive next winter’s heating bills.

Because his project is considered a model for retrofitting homes to be energy efficient, suppliers have donated windows and materials, halving the estimated price tag of $100,000.

State officials are keenly interested because his experience could figure into future building codes and zero-energy home initiatives. Ian Bowles, the secretary of energy and environmental affairs for Massachusetts, visited the construction scene where he spoke to a camera crew from Planet Green’s Renovation Nation cable show.

At the national level, making homes energy efficient is becoming serious business. Worldwide, it is estimated that buildings account for between 30 percent and 40 percent of energy use.

As part of a planned stimulus spending project, President-elect Obama said that money will be available to retrofit schools and government buildings to be more energy efficient. During his campaign, he called for lawmakers to fund a program to weatherize homes of low-income people, considered a cheap way to reduce energy use in homes.

Project breakdown
The genesis of the superinsulation project was simply that Cheimets felt cold in his two-family home. He tried a number of low-cost air sealing tricks like caulking and replaced some windows but wasn’t satisfied.

Alex Cheimets in front of his soon-to-be superinsulated home.

He and the building’s other owners also knew that they had to reshingle the building at some point. Cheimets, a engineer who works in the appliance industry, had heard of superinsulation and started researching it.

“We knew that reshingling was a once-in-a-lifetime job, so we thought, let’s do it right,” he said. “And once we decided to do the research on superinsulating, things moved along quickly.”

Frustrated by the lack of available information, he contacted officials at the Massachusetts Department of Energy Resources who offered him some guidance on technical aspects of the project. Cheimets also discovered Boston-based Building Science Corp., a company which specializes in superinsulation and had done a handful of home retrofits.

Building Science recommended Massachusetts green building contractors, Synergy Companies Construction, who are now in the middle of the project.

Already two layers of insulating board–seven inches worth–have been added on top of the existing roof, giving it an R-value of 59. On the walls, there are also four inches worth of foam board. In addition to the existing cellulose insulation, the walls now have an R-value of 39. New energy-efficient windows are being added as well.

The R-value measures how well insulation can keep heat from penetrating a structure, with a high R-value meaning more insulation. How much a building needs depends on the region and type of construction, according to the Department of Energy. But Cheimets’ home will significantly exceed federal recommendations of R 49 for an attic (which is not commonplace) and R 13 for walls in Massachusetts.

In addition to insulating, the contractors are trying to seal the home, an often-overlooked aspect to weatherizing. Cracks between the foam boards are taped and contractors are adding foam insulation in crawl spaces and on the basement ceiling.

Because they are adding four inches of foam insulation to the home’s walls, there is a small well outside of the windows.

Cheimets is pleased to see the superinsulation project finally see the light of day, but he admits some aspects make him nervous.

By sealing the air, the building runs the risk of trapping moisture inside the walls, particularly during the winter. He said experts at the state and at Building Science Corp. told him that air quality and moisture should not be a concern given that enough air manages to get indoors.

To be sure, they are installing two ventilation systems (an air-to-air heat exchanger) to recycle the air, which will be most important during the winter. There are also carbon monoxide monitors.

Being part of a pilot project, Cheimets will need to gather data on humidity and temperature levels and how much oil he is using. His home is being equipped with four sensors from Onset Computer, as are his neighbors on both sides (both scientists). Once a month, they will download data using an USB connection to a laptop and report it to the state.

He is considering alternatives to his oil furnace, such as a geothermal heat pump, or getting solar panels.

From an environmental perspective, Cheimets sees some irony in the fact that he’s using a garage-full of oil-based foam insulation to save oil in his home. Even save much during heat pump usage. But he thinks superinsulation is a way to make a big leap in energy conservation–potentially in stages–without having to rebuild or alter the look of existing homes.