insulation

Stupid Multifamily Construction Tricks

Posted on March 29,2015 by CarlSeville in air barrier

Although I spent most of my construction career working on single-family homes, the primary subject of this great website, I find that my current work involves primarily multifamily projects — mostly low-rise and mid-rise apartments that are seeking green building certification. In these projects, my partner and I continue to see both new and recurring problems that are not resolved in the design phase, only to be pushed down to the field to be figured out — on a tight budget, in a hurry, and often in the cold or rain.

Passive House is Looking for a Few Good Men (and Women)

Posted on March 29,2015 by CarlSeville in certification

I make no claim to being an expert on Passive House, but ignorance has never stopped me from expressing my opinion before. Among the major complaints about the Passive House standard is that it has inflexible energy use requirements, and the European-designed program does not effectively address the wide range of U.S. climate zones. This inflexibility often leads those who pursue this certification to install enormous quantities of insulation, particularly under slabs, which raises a variety of questions and concerns about the usefulness of this practice.

Second Guessing an Insulation Upgrade

Posted on March 29,2015 by ScottG in insulation

Is there anything worse than getting midway through a renovation and then suddenly wondering whether you've got some important detail all wrong? That seems to be the predicament of William Lucrisia, who's in the midst of an insulation upgrade at his house north of Seattle. "The house was heated by propane," he explains in a Q&A post at Green Building Advisor. It was a cost that was hard to get hold of, especially with some of the design [features] of the house (high ceiling)."

An Energy Upgrade On a Budget

Posted on March 29,2015 by ScottG in air-source heat pump

Christian Rodriguez has taken an important first step in improving the energy efficiency and comfort of his 1880s home by arranging for an energy audit. With the results in hand, his first step was to air-seal the attic and add 20 inches of cellulose insulation. "This made quite a difference both in comfort and heating bills," he writes in a Q&A post at Green Building Advisor. Now comes a difficult decision: what to do next.

Spray Foam Insulated Homes Need Ventilation

Posted on March 29,2015 by ab3 in air sealing

Most installations of spray foam insulation, when properly installed, act as an air barrier. When you use it instead of the fluffy stuff (fiberglass, cellulose, cotton), a house will be more airtight. That's good.

When a house is airtight, the nasties in the indoor air tend to stick around. Volatile organic compounds (VOCs), water vapor, odors, radon, and other stuff you don't want to immerse yourself in make the home's indoor air quality worse.

The Diminishing Returns of Adding Insulation

Posted on March 29,2015 by ab3 in conduction

If you're building a house and want to have a really good building enclosure, you need it to be airtight, handle moisture properly, and have a good amount of insulation. Ideally, you'd also consider the effects of solar radiation on the home, but for now let's just focus on the insulation. What exactly is "a good amount" anyway?

Use of Spray Foam Insulation Drops

Posted on March 29,2015 by ScottG in fiberglass

Builders may be backing away from spray foam insulation. Between 2008 and 2012, spray foam's market share grew from 3% in new home construction to 11%, a nearly four-fold increase. But last year, according to a survey from the Home Innovation Research Labs, its market share fell to about 8% as more builders returned to an old favorite: fiberglass.

What’s the Best Way to Insulate Crawl Space Walls?

Posted on March 29,2015 by ScottG in crawl space

Andy Chappell-Dick is at work on a house in Climate Zone 5 where the task at hand is to upgrade a crawl space by adding insulation as well as a membrane to block the infiltration of moisture. The catch? The owners want to avoid the use of rigid foam insulation if at all possible.

What’s More Important, Air-Sealing or Insulation?

Posted on March 29,2015 by ScottG in air sealing

Green Building Advisor reader Ani Brown is getting ready to build a new house, and like most people in her position Brown will have to make some important choices on how to make the most of a limited construction budget. Her immediate concern is insulation and air-sealing, two related details that will have a lot to do with how comfortable and durable the new house will be.

Why Is My House So Hot?

Posted on March 29,2015 by ScottG in air conditioning

When Jeff Watson realized that the insulation on his attic floor was rated at R-11, he did what any energy professional would have suggested: he added more insulation. He air sealed the attic floor, added ventilation baffles where necessary, and blew in a thick layer of R-60 insulation. But he isn't entirely satisfied at the results. "As expected, the temperature in the house doesn't fluctuate as much," Watson writes in a Q&A post at GreenBuildingAdvisor. "However, I feel as if I'm using AC more.

Multifamily Green Building Certification Still Has Issues

Posted on March 29,2015 by CarlSeville in air sealing

Much of my work these days involves certification of multifamily buildings, and, thanks to a boom in apartment construction, my partner and myself are staying occupied. The one major contrast from single-family residential work, with which I am most familiar from my days as a contractor, is the long lead time. I still find it amusing that I sign a contract, have an initial start-up meeting with the developer and contractor, and often don’t see the project for another year or more, when the builder is ready for our insulation and air-sealing inspections.

What Architects Need to Know About Attic Kneewalls

Posted on March 29,2015 by ab3 in air barrier

We were working on a project, so we got a set of plans to get started. It includes the attic kneewall and vaulted ceiling section you see at right. This is typical of plans that architects draw, and builders build houses this way all the time. Unfortunately, it contains several errors. Can you spot them?

What Fruit Flies Taught Me About Sustainable Living

Posted on March 29,2015 by CarlSeville in fans

Last summer my house developed a fruit fly infestation, due to the fact that I had a lot of fresh fruit sitting around ripening on my counters. I recall once using aerosol bombs to get rid of them, but I figured this time around I would look for a slightly less toxic solution. A quick web search turned up details for a standard fruit fly trap, consisting of a jar with a little cider vinegar and dish soap, covered with clear plastic with a few holes in it. The flies are attracted to the vinegar, fly in, get coated with dish soap, and drown in the cider.

The Best Way to Insulate a Floor

Posted on March 29,2015 by ScottG in cold floor

Jim Wright's house in western Arkansas has a pier foundation that elevates floor framing about 40 inches off the ground. Unlike a house with a basement, crawl space, or slab foundation, there is no enclosure at the bottom of the house, so the floor is more or less like another exterior wall. How, Wright wonders, should this be insulated?

California Study Shows Big Savings in Home Energy Retrofits

Posted on March 29,2015 by ab3 in air flow

At the Forum on Dry Climate Home Performance earlier this year, I got to hear three building science experts talk about a really cool research project they've been working on in Stockton, California. Bruce Wilcox, John Proctor, and Rick Chitwood (Wilcox and Proctor are shown in photo at right) filled us in on the Stockton project, which now has two years of data and shows some really impressive results.

Does Open-Cell Spray Foam Really Rot Roofs?

Posted on March 29,2015 by ab3 in attic

Murmurs and hearsay about open-cell spray foam insulation have been gaining traction for a while. It rots roofs, people have told me. Not long ago, someone even told me that in Florida, roofing companies won't let their workers go up on roofs with open-cell spray foam because the roofs are so spongy, the guys fall right through. Open-cell spray foam is getting a bad reputation among some people in the construction industry. But is it deserved?

Flash and Batt in the Roof

Posted on March 29,2015 by ScottG in attic insulation

"Flash and batt" is an insulation technique that combines the air-sealing superiority of spray foam insulation with the cost benefits of fiberglass batts. An inch or two of polyurethane foam seals the cavity and the batt insulation adds R-value without costing an arm and a leg. That's roughly the plan Dave Frank is considering for the roof of a house — presumably his own house — in Climate Zone 5. But his plan contains a twist: He wants to spray the underside of the roof deck with foam and install the batts between the joists at ceiling level.

Dealing With Cold Weather in Climate Zone 3

Posted on March 29,2015 by CarlSeville in cold weather

We had some serious cold weather down here in Georgia recently, and although it didn’t come close to Martin Holladay’s recent experiences in Vermont, the low temperatures were a bit of a shock and caused a lot of problems.

Why Is This Sheathing Moldy?

Posted on March 29,2015 by ScottG in central-fan-integrated supply ventilation

Brian Lent has discovered something in his walls that no homeowner wants to see: mold. Preparing a ground-floor room for drywall, Lent pulls some fiberglass batt insulation from a 2x6 stud cavity and notices the back side of the OSB sheathing is damp. A moisture meter reveals that in 80% of the bay, the moisture content is 66% or higher. Moisture and mold are heaviest at the bottom of each bay.

Register for a free account and join the conversation


Get a free account and join the conversation!
Become a GBA PRO!

Syndicate content