The Right Way to Build: Insulation

With all the talk about building green these days, you would think it is something new, maybe solar panels on the roof and high-tech solutions with complicated circuitry and untried ideas. The truth is, you can reduce the energy consumption of a new home or retrofit by as much as 70%, with conventional construction done right.

Think of it. If all the standard energy-saving measures like insulation and caulking were done with the same care and attention to detail as the cabinetwork and finish carpentry, the air you pay to heat would stay in the house and keep you warm, instead of finding its way outside through the walls and attic.

There is a standard of proper wall and ceiling insulation, but the truth is very few of those people whose job it is get it right. This is partly because it is one of the lowest-paid jobs in the business, and the workers are often paid by piecework. It is also because too few people–including owners, contractors, and building inspectors–insist on a good job of installation. The result is–yes the work is done cheaply and quickly. It is the building owners who pay for it over the years, in excess energy bills that need never have been so high.

The standard is known specifically as “Quality Insulation Installation,” or QII. When I asked an insulating contractor if his company provided QII, his answer was, “We train our installers well.” It was his business, and he hadn’t even heard of the standard!

Here is a part of the procedure, paraphrased from Energy Star (energystar.gov):

a. Wall stud cavities should be caulked or foamed to provide a substantially air-tight envelope to the outdoors, attic, garage and crawl space. Top and bottom plates should be continuous and have any openings sealed. Special attention should be paid to plumbing and wiring penetrations through the top plates, electrical boxes that penetrate the sheathing, and the sheathing sealed to the bottom plate.

b. Pay special attention to installation of air-tight air barriers for walls adjoining exterior walls or unconditioned spaces, including walls behind showers/tubs and behind fireplaces, insulated attic kneewalls, staircase walls, the intersection of porch roofs and exterior walls, and skylight shaft walls.

c. Fill each cavity side-to-side, top-to-bottom, and front-to-back. Batt insulation should be installed to fill the cavity and be in contact with the sheathing on the back, the studs at the sides, and the wallboard on the front – no gaps or voids.

Before you spend money on new windows, or blow-in insulation to the walls of your older home, do these two things first. Go in your crawl space and attic, and air-seal every opening you can find with spray foam insulation, and insulate the attic to R-30 or better (have an electrician take a look up there first, to be sure your any lighting or wiring is suitable for burial in insulation). You’ll be surprised and the new-found comfort. Some people will tell you doing these things is a waste of money, but the truth is they are the cheapest investment you can make, with the best results in savings and comfort.

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The Right Way to Build: Insulation

With all the talk about building green these days, you would think it is something new, maybe solar panels on the roof and high-tech solutions with complicated circuitry and untried ideas. The truth is, you can reduce the energy consumption of a new home or retrofit by as much as 70%, with conventional construction done right.

Think of it. If all the standard energy-saving measures like insulation and caulking were done with the same care and attention to detail as the cabinetwork and finish carpentry, the air you pay to heat would stay in the house and keep you warm, instead of finding its way outside through the walls and attic.

There is a standard of proper wall and ceiling insulation, but the truth is very few of those people whose job it is get it right. This is partly because it is one of the lowest-paid jobs in the business, and the workers are often paid by piecework. It is also because too few people–including owners, contractors, and building inspectors–insist on a good job of installation. The result is–yes the work is done cheaply and quickly. It is the building owners who pay for it over the years, in excess energy bills that need never have been so high.

The standard is known specifically as “Quality Insulation Installation,” or QII. When I asked an insulating contractor if his company provided QII, his answer was, “We train our installers well.” It was his business, and he hadn’t even heard of the standard!

Here is a part of the procedure, paraphrased from Energy Star (energystar.gov):

a. Wall stud cavities should be caulked or foamed to provide a substantially air-tight envelope to the outdoors, attic, garage and crawl space. Top and bottom plates should be continuous and have any openings sealed. Special attention should be paid to plumbing and wiring penetrations through the top plates, electrical boxes that penetrate the sheathing, and the sheathing sealed to the bottom plate.

b. Pay special attention to installation of air-tight air barriers for walls adjoining exterior walls or unconditioned spaces, including walls behind showers/tubs and behind fireplaces, insulated attic kneewalls, staircase walls, the intersection of porch roofs and exterior walls, and skylight shaft walls.

c. Fill each cavity side-to-side, top-to-bottom, and front-to-back. Batt insulation should be installed to fill the cavity and be in contact with the sheathing on the back, the studs at the sides, and the wallboard on the front – no gaps or voids.

Before you spend money on new windows, or blow-in insulation to the walls of your older home, do these two things first. Go in your crawl space and attic, and air-seal every opening you can find with spray foam insulation, and insulate the attic to R-30 or better (have an electrician take a look up there first, to be sure your any lighting or wiring is suitable for burial in insulation). You’ll be surprised and the new-found comfort. Some people will tell you doing these things is a waste of money, but the truth is they are the cheapest investment you can make, with the best results in savings and comfort.

First published in the Pacifica Tribune 3/24/10

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1. Energy Efficiency and “Green Building”

If every attic in America were insulated to the standards mandated by the state of California, the United States would no longer need to import foreign oil. That is only one measure of the amount of fossil fuel energy wasted nationwide. But energy efficiency is about more that just conservation, it�s about comfort in our homes whatever the weather might be outside them. Innovative concepts like Net-Zero Passive Homes in Germany that have no need of a furnace, or properly insulated homes in Sacramento that have an annual heating/cooling cost of $250/year, are quick examples of energy-efficiency that involves no unusual construction practices or expenses. With a photovoltaic array and a solar water-heater on your roof, you can say goodbye to utility bills. And if we can collectively reduce the emissions of greenhouse gases, we may yet save the polar icecaps.

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Design and Construction Techniques to Use Less Wood

Thinking about adding something to your home—a new deck, a master bedroom addition, or a kitchen remodel? Given today’s bright focus on green building, let’s look at ways to get the same great result using less wood.

The most important thing you can do is plan your project carefully.  No matter how large or small it is, there are plenty of ways to avoid waste.

First, don’t build more than you really need.  If 150 square feet of new room or deck is all you need, why make it any larger?  Yard space for landscaping and recreation is just as important as finished living space, and probably easier to maintain.

As you move on to framing, be aware that some common practices sacrifice trees and energy efficiency, yet add nothing to the strength of the structure. You can use less wood, less time, less money in the framing by not using double trimmer studs and sills at window openings, 4×12 headers at openings in non-bearing wall, three-stud corners. Instead, employ Optimum Value Engineering or OVE and use studs placed at 24” on center rather than the common 16”, single rather than double top plates (bearing walls must have joists and rafters stacked above the studs), two-stud corners, and a variety of other practices. These practices can save up to 30% in lumber expense.

You can also consume less raw wood by working with engineered lumber. Engineered wood is made from small-diameter, fast-growing plantation farms and are usually straighter and stronger than solid-sawn products. Ask for products such as truss joist I-beams (TJIs), parallel-strand lumber (PSLs), oriented-strand board (OSB) and laminated wood products. These manufactured lumber products are all in common use today.

When you do build, build to last.  Most commonly used woods will not stand up well to insects or the weather, and all of them (unless especially treated) are subject to fungus damage when they gets wet and cannot dry out.  It’s critically important to understand which materials to use outdoors, and how important flashing details are where the construction is exposed to rainfall.  A 1” mis-cut at a crucial flashing junction can lead to thousands of dollars worth of damage in only a few years.  Water resistant finishes—paints and penetrating oils—are also important in keeping the wood safe from fungus damage.

There are a lot of manufactured products available now that take the place of, and weather better than, the wood used outdoors just a decade age.  Cement-based siding installs and looks like wood when painted conveys the same look.  There are a variety of composite decking materials that look much the same as, and last much longer than redwood decking.  Vinyl fencing is now available in a variety of styles, and has the added advantage of never needing paint.

Most molding profiles are now available made from plastic with wood veneer, that will cut, stain, finish, and install just like hardwood trims.  Beautiful “engineered” flooring of hardwood veneers comes prefinished and can be installed in much less time than hardwood nailed down strip by strip and sanded and finished in place.

There is a world of new products and techniques out there.  If you take the time to educate yourself in their proper application and installation, you just might help keep some of the trees in the forest, and some of the green in your pocketbook.

David Hirzel is a Green Point Rater and residential building designer serving the Peninsula and the central California coast since 1983.

(First published in San Mateo Times, August 13, 2009)

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