Sealed With Care

THE HOUSE CHRONICLES SERIES LOOKS AT THE INSULATION THAT’S REQUIRED TO MAKE A NEW HOME COZY AND ENERGY EFFICIENT

It was that dramatic moment in May when the rough carpenters finished their work and we walked into the large wooden shell of this new house for the first time.

Oh, no. At the back of the dining room, where three walls meet on an angle to form the bay, you could see sunshine through gaps between the boards.

“Look at this,” we said to Matt Kime, youngest son in the Kime family of builders and project manager for this house.

“The energy seal will fix that,” he said.

Of course. One reason the Free Press picked RDK Homes for the House Chronicles — the Free Press’ spring and summer project to document the building of a house — was that the company’s houses give us the chance to explore some good new products and processes. Without being lavish, the houses go beyond what’s baseline for a medium-priced subdivision house.

In insulation, this extra is the Nelson Energy Seal. Like extreme sports, it’s extreme caulking that exceeds what most insulation companies offer as standard.

The process is done in two stages — the first after the rough frame is built, but before it’s insulated, the second after drywall is hung.

You’ll become a convert to extreme caulking if you ever stand inside a justframed house when the sun is behind it and you see how shafts of light shoot through gaps between wood and wood — spaces that might be a quarter-inch high and 20 feet long. It’s estimated that the air leaks in the frame of a standard house add up to the size of an open window.

This matters. The insulation package that goes into your new house will be one of the most important factors in how much you enjoy it.

Feels like home
The pluses to good insulation are more than saving money on energy. A house with cold spots will never feel cozy in the winter, even if you crank up the heat.

Heat and cold always move toward each other. If areas of your house leak heat, inside air always will be moving, as heat travels to cold spots. You’re not only paying for heat that’s lost, you’re sitting in a constant draft.

In Michigan, home insulating codes are so-so — better than they used to be, but well short of what’s recommended by the U.S. Model Energy Code for this climate. For a northern state, we have one of the weaker codes.

So a smart new-home shopper has two ways to go.

  • If you choose a builder who uses today’s standard code — and most do try to ensure that you get good work.

  • As an alternative, look for a builder who gives you more than Michigan’s energy code requires. 

Here are details about both paths:

Standard Michigan insulation
At the majority of subdivisions, the standard package you’ll be offered is R13 insulation in the walls, R30 in the ceiling, plus a house wrap like Tyvek. The “R” stands for resistance to heat and the higher the number, the higher the insulation quality.

R13 usually is achieved by unrolling fiberglass batting into the 16-inch-wide spaces between the wall studs. Most often you’ll see the distinctive pink product from Owens Corning.

The fiberglass might be exposed, or it might come in a paper wrap that has a thin coat of tar on the inside for a partial vapor barrier. That’s good because the paper edges can be stapled to the wood studs for a snugger fit.

If your house is framed with 2-by-4s, as most are, the insulation goes into a wall cavity 3˝ inches deep. Usually R13 is the most insulation you can fit into that space.

The ceiling gets R30 insulation, more than the walls, because warmed air rises. Some common forms are fiberglass batting, blown-in cellulose or a combination of the two.

Sloppy installation can greatly reduce the effectiveness of the insulation. Compressing it — for example, behind plumbing in the walls — cuts the R-value.

Holes have to be cut for electrical switches and plugs. They should be as small and precise as possible. In a sloppy job, you see gaps around the windows and doors or the reverse — insulation stuffed messily around door and window openings, plumbing and electrical boxes.

Pretty in pink
At the House Chronicles home in Van Buren Township, our insulation is a joy to the eye.

This is the typical product — pink batting wrapped in paper. But the subcontractor who installed it, Chris Leach, owner of Arctic Insulation in Plymouth, stapled it in as precisely as fine sewing.

It looks tighter and neater than photos in the Owens Corning promotion kit. You almost hate to see the drywallers cover it.

Leach has not tucked insulation behind the areas like the electrical boxes, because this house will get Nelson Energy Seal. That includes insulating foam sprayed around all areas that required openings be cut in the batting, for example, electrical boxes and plumbing.

Most, though not all, builders also add house wrap like Tyvek, which stops air infiltration while it lets moisture escape from the wall cavity. It’s so common now that unless the builder has substituted another air barrier, you might be hesitant about buying in a subdivision that has no house wrap or charges extra for it.

Add insulation to your list of items to check before you choose your builder and are visiting construction sites.

Finally, try to visit your home while your insulation is being installed.

Upgrading your insulation
Traditional fiberglass batting is being used in at least 90 percent of subdivision houses today, not necessarily because it’s better than other insulation, but because it’s what most crews are used to installing.

But even using fiberglass batting, you can improve on that R13/R30 code minimum, and about 20 percent of metro Detroit builders offer a better package. Macomb County’s builders, especially, sometimes give better than- minimum insulation.

Here are four ways to get a snugger house while using fiberglass batting.

Rigid foam-board insulation: This consists of 4-by-8-foot boards of foam plastic attached to a backing. It’s applied like a shell around the exterior of your house before bricks or siding are applied.

Foam-board insulation gives good added R-value for your walls, plus an added air barrier, at a moderate price. Most manufacturers — Dow, Owens Corning and others — say they can make foam plastic without using ozonedamaging chlorofluorocarbons, or CFCs.

One inch of foam board has an R-value of 4 or 5. In metro Detroit, you’ll often see a half-inch board for an added R2, plus the added air barrier. The giant Pulte Homes adds an R3.1 foam board to all houses it builds in Michigan, says Great Lakes marketing director Mark Powers. Some mid-sized and small-sized builders do as well. At Dow, a representative estimated that adding half-inch foam board to a 2,500-square foot house would cost $650-$750 installed.

More attic insulation: The cheapest, easiest improvement you can make is increasing attic insulation from R30 to R38. You get R38 with 12 inches of fiberglass or 10 inches of blown-in cellulose. Because you already have some insulation, you only have to augment it. It’s fine to combine fiberglass and cellulose. Using either, materials to make this increase would cost $200 to $400 in a two-story, 2,500-square-foot house, according to prices from Home Depot. Installation might roughly double that.

Nelson Energy Seal: A laborious process in which workers come to the house twice and seal every possible spot that air could pass through, with an expanding foam caulk. Any company is free to caulk like this, but around here it’s usually Nelson Energy Seal, founded by D.R. Nelson.

It’s far more than the standard caulking, and the Nelson company checks houses frequently with the blower-door test. This is the insulation industry’s accepted method for measuring air-tightness. The house is closed up; the door is sealed and attached to a device that pumps in air under pressure. A built-in gauge measures how much air the house lets escape.

Some areas are especially vulnerable to air leaks, Nelson says, like the dining room bay in the House Chronicles home.

“Bays are notorious,” he says “They have lots of gaps just by their nature.”

When you are new-house shopping, give extra points to a builder who includes this super caulking. It’s about a day’s labor after the worker becomes skilled, Nelson says. It costs the builder $500- $700, and the builder usually has to explain to the buyer why it’s worth having.

Last year roughly 3,000 new houses or condos in metro Detroit got Nelson Energy Seal, Nelson estimates. That’s about one in eight of the houses built.

Pulte puts it in all houses here. “It’s all about air and water infiltration,” says Powers. “We certainly found we had fewer callbacks,” he said of home owners’ complaints.

Some builders who add Nelson Energy Seal for free are RDK Homes, Moceri Development, Multi Building Co., Leader Homes, LoPiccolo Homes, Kingsway Builders, Tri-Mount Development and some of the Toll Brothers subdivisions. A few builders offer it as an option.

Building with 2-by-6 construction, rather than 2-by-4: This gives you a terrific, solid house, and the deeper wall cavity you get with 2-by-6 studs allows great insulation.

A 2-by-6-built house gives you a wall cavity of 51/2 inches, a depth that holds R19 insulation easily. Typically, a builder who goes this far also will add foam board to the outside, and you get walls of about R22.

Not many subdivisions are built this way, though. One-of-a kind houses sometimes are, and a few smaller-scale builders like to build 2-by-6 houses. A high-volume builder who works exclusively with 2-by-4s can’t switch easily to 2-by-6s at your request. The transition requires a number of changes, for example, the framing of doors and windows.

Measuring sticks
The Gold Standard would be the U.S. Department of Energy’s recommendations for Michigan, as found in the Model Energy Code.

Roughly, they call for at least R15 walls plus house wrap, R38 ceiling, insulation inside or outside the basement, energy-efficient sealed, two-pane windows made of wood or with a heat barrier between inside and outside. These guidelines are not absolute; increasing one component can allow decreasing another.

You could achieve R15 walls by adding a half-inch of foam board insulation to a standard R13 fiberglass or cellulose-insulated wall.

You could achieve an R38 ceiling with 12 inches of fiberglass or about 10 inches of blown-in cellulose, says insulator Chris Leach.

The easiest way to insulate basement walls is with foam board around the side. You can also insulate inside, or you can build the basement with one of the new precast insulated components.

The best insulation package you’re likely to see in new metro Detroit subdivisions is this:

  • Walls of about R16 — foam board over standard insulation.

  • Ceiling of R38, fiberglass or blown-in cellulose.

  • Nelson Energy Seal.

  • Basement insulation of about R5 foam board around the exterior. 

Finally, there is a touchstone if you are determined to find extra good insulation — the Environmental Protection Agency program Energy Star.

Energy Star-approved houses will use 30 percent less energy than houses built to the Model Energy Code — a very high standard.

A few metro Detroit builders offer this, and the number appears to be growing.

For example Lombardo Cos., a large Macomb County builder, offers an Energy Star option on houses at Timber Mill North, a Washington Township subdivision of houses in the higher $200,000s.

For $2,995, you get a house that meets Energy Star standards with foam board on basement walls, blown-in cellulose, higher R-values in walls and ceiling, extra leak sealing and a furnace that’s 90-percent-plus efficient.

You’ll find a list of Michigan builders affiliated with Energy Star on the Web at www.epa.gov under Energy Star, then Consumers. Or leave your name and number at 888-782-7937 anytime.

Next week: Come back to the Free Press to watch the House Chronicles home get its plumbing, heating and electrical systems, and learn about some interesting choices among these essential house components.

NEXT >