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LAYERING UP FOR WINTER: Insulation retrofits for your home

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Rural brick house


Layering Up for Winter: Insulation Retrofits for Your Home (via MarketWire)

December 05, 2012 10:40 ET OTTAWA, ONTARIO–(Marketwire – Dec. 5, 2012) – If you own an older home, chances are that you are always on the look-out for ways to reduce your heating costs. Adding insulation to your home not only helps you save money right now, it’s also a way to “future proof” your home…

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December 10, 2012 |

RETHINKING GREEN ROOFS: 9 points to consider before greening your roof

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Green roof on MEC building

In this age of energy-efficiency another method of building the top of a building is taking root: green roofs. On such “upland” terrain one can grow foods from strawberries to cornstalks, enjoy the view, even have fountains and topiary—whatever one’s fancy and budget will allow. LEED awards points for this construction on the grounds that it “can reduce roof temperatures from summertime highs of 150 degrees to less than 80 degrees, can reduce energy demand by more than 50 per cent annually, can minimize impact on microclimate and natural surroundings and can increase oxygen through photosynthesis.”

“Can”? That little three-letter word as recruited above could also mean “might not,” probably won’t,” “wouldn’t in a million years,” and a host of other adverse implications. In fact, each of the four conditions listed above “can” under a minority of circumstances prevail. However, while LEED awards points for green roofs, it does not make the following points about certain majority aspects of this construction:

1. Green roofs cost a lot. Typically 15 to 25 dollars per square foot on top of one’s initial cost. This could tilt the scales of this shelter’s potential cost-effectiveness from positive to negative.
2. These roofs weigh a lot. Usually 40 to 80 pounds per square foot, some as much as 200 psf; and all supporting structure below down to the ground must be made larger. To indicate how deceptive some promotions of green roofs have been regarding this, consider the recently built green roof on the Chicago City Hall, an impressive project that received rave reviews in numerous architectural magazines. However, only one of these periodicals mentioned (in a short sentence sequestered deep in its text) that what made all this heavy construction possible was that the building was originally designed to support the construction of an added floor; and the weight of the green roof replaced what would have otherwise been the weight of the future floor without requiring any revisions in the structure below. Every article about this roof should have made this vital point clear. Or else—again—when someone who constructs this idea learns that it or some other ecologically promoted concept isn’t what they were led to believe, the tide of one’s opinion will likely turn from delight to dissent, and in the company of one’s colleagues they will colloquially cast a vote against rather than for the reality—often with a fervour that far outweighs any feeling they might have otherwise expressed; for in such scenarios, censure generally outpaces praise.
Layers of a living roof3. Topsoil can erode and subsoil can slip during heavy rains. Though LEED’s guidebook says, “All garden roofs decrease stormwater runoff volumes substantially,” this is false. Garden roofs may decrease stormwater runoff during short light rains; but during severe storms when the roof’s soil has become saturated, stormwater runoff will not be less than on standard roofs and this is when topsoils and subsoils will likely erode and slip.
4. After construction most green roofs need almost daily horticultural attention: mowing, weeding, erosion control, and precise watering (enough to encourage growing but not enough to initiate erosion and slippage).
5. Green roofs attract bugs, rodents, and other members of a thriving ecosystem, even on tall buildings.
6. Green roofs require access—not by a ladder over a gutter but by a railed central staircase. A good central entry is a stairwell that rises into a small greenhouse with a door from which you step onto the roof. Also, areas that can be occupied should be enclosed by chest-high parapets; and any walkways or terraces should be masonry and not wood, which requires waterproofing above, airspaces below, and toxic rot-proofing all around.
7. These roofs often require electric outlets, landscape lights, hose outlets, and related mechanical equipment.

8. The roof substrate can leak, and when it does it is difficult and expensive to repair.

9. A green roof can be a fire hazard. If the roof’s vegetation turns brown due to lack of water, a brush fire could start there and spread indoors or to other buildings.

LEED’s guidebook also says:

a) “Some green roofs have grasses and plants that require no watering,” (False: all plants, even cactus, require some watering, which means monitoring, which means access).

b) “All types of green roofs have longer lifetimes than conventional roofs,” (False: if they do last longer it is because they must be constantly maintained in ways that are not required with standard roofs).

c) “Green roofs provide lower maintenance than standard roofs.” Hah! See #4 above.

If you want a green roof to increase a building’s insulating ability and decrease its water runoff, there are better and cheaper ways to do these things. Esteemed building scientist, Joseph Lstiburek, Ph.D. says:

Vegetative roofs? Grass and dirt are not energy efficient. Work with me here. Which saves more energy: two inches of dirt or two inches of insulation? Which saves more energy: grass or a white-coloured membrane? Which is more expensive and does not save energy: grass and dirt, or insulation and a white-coloured membrane? Which needs to be watered to keep the grass from dying and blowing away?

On the other hand, if you love gardens and want to transform a barren tract wracked with violent temperature extremes into a meadowy landscape that blooms with wildflowers, bustles with butterflies and birds, is threaded with pleasant walks and patched with relaxing terraces, and offers fine views above the bugs and closer to the stars, then you deserve all the joys that gardens can give you, all the praise that periodicals may rain on you, and all the points that LEED may award you.

One bona fide technique that will improve the thermal performance of many a roof is to do what Joseph Lstiburek mentioned above: paint it white. According to an article in The New York Times, such roofs not only are “An energy saver but also a way to help cool the planet… These materials reflect as much as 90 per cent of the sun’s heat energy… Studies show that white roofs reduce air-conditioning costs by 20 per cent or more.” Even Frank Lloyd Wright got into this act—years before anyone else did—by saying: “A white-topped roof is economical partly because white, of course, reflects heat rather than absorbs it.” As for the possibility that white roofs could lead to higher heating bills in winter, Home Power magazine says: “Summertime air-conditioning savings from choosing a light-coloured roof will most likely outweigh the heat gained in winter by using a dark-coloured roof [because] the winter sun is available for a shorter part of the day, is lower in the sky, and its light passes through more atmosphere than that of the summer sun.”

Three months before the New York Times article appeared, I painted 2,400 square feet of my house’s roof with SolarFlex 287 SF, a thick white elastomeric roof coating made by the Henry Company of El Segundo, California. During the past two summers the rooms below have been notably cooler than in previous years, and they weren’t any cooler during winter.


After graduating from the Cornell School of Architecture in 1964, Robert Brown Butler has worked as a carpenter, contractor, and registered architect. Through the years Mr. Butler has received a variety of honors for his creative work. He is the author of The Ecological House, which introduced many ideas that are further advanced in this volume, among other books. This excerpt reprinted with permission from Architecture Laid Bare!: In Shades of Green, by Robert Brown Butler. © 2012, Robert Brown Butler.

photo courtesy 416style

December 8, 2012 |

WHY BUILD GREEN? Infographic explaining green building’s many benefits

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Green building is smart building. Aside from their obvious benefit to the environment, green buildings deliver financial savings, are more comfortable, healthier, return higher productivity rates and have higher resale values. See this infographic for a quick look at why building green makes so much sense. And for a more detailed understanding of green building refer to the second page of our green building basics guide: Why build green?

Why build green? [infographic]

 

The environmental impact of buildings

  • 50% of natural resources
  • 25% of landfill waste
  • 12% of water consumption
  • 10% of airborne particulates
  • 35% of greenhouse gases
  • 39% of energy use

Payback

Conventional home = Average building costs of $125/sq. ft. = $150,000
Annual energy costs = $3000

Green home = Average building costs at a 2% premium = $153,000
Annual energy costs = $2250 (25% savings)

Average payback period = 3 years (without government rebates, 4 to 5 years)

Perception vs. reality

LEED-certified buildings cost on average 1 to 2 percent more than comparable conventional buildings, yet public perception is quite a different thing.

When asked “if there is a significant cost difference between green building and standard building products and practices?” building professionals answered:

62% – Yes
26% – No
12% – Unsure

Other financial benefits

Property value – green buildings show higher property values and average sale price increases of more than $20 per sq. ft.

Decreased demand on infrastructure – high performing buildings demand less energy and water, which decreases the strain on common resources and allows infrastructure capacity to extend farther.

Increased productivity and attendance – productivity gains of 2-10% and a reduction of 35% for absenteeism have been reported.

Improved sales – 40% increase in sales reported in buildings that use skylights rather than electric lighting.

Gas savings – A green built community can result in annual gas savings of as much as $1000 per house-due to proximity to necessary infrastructure.

Investment decision – Leed buildings have an ROI of 15 to 20% just based on energy efficiency measures.

Environmental benefits of building green

Indoor environmental quality (IEQ)

  • 9 to 50% reduction in sickness
  • 9 to 20% reduction in communicable respiratory diseases
  • 18 to 25% reduction in allergies and asthma
  • 20 to 25% reduction in non-specific health and discomfort

Site

  • Reduced sprawl
  • Preservation of natural spaces, wildlife habitat and native species
  • Minimized reliance on cars from improved access to infrastructure
  • Reduced soil erosion from sustainable landscaping
  • Minimized light pollution from reduced and optimized lighting

Energy and atmosphere

  • Reduced greenhouse gas emissions
  • Reduced energy consumption

Materials and resources

  • Waste reduction
  • Locally sourced materials and resources
  • Minimized material usage due to durability
  • Renewable resources
  • Natural materials

Water

  • Reduced water consumption
  • Water reuse and collection

 

Sources:

Sustainable Rhythm: Opening the Door to Green Building
GSA: LEED Cost Study
Greening Buildings and Communities: Costs and Benefits
Costing Green: A Comprehensive Cost Database and Budgeting Methodology
Resource Efficient Housing Inc.
ENERGY STAR: ENERGY STAR benefits
City of Edmonton: Residential Property Tax & Utility Charges Survey
USGBC: Making the Business Case for High Performance Green Buildings
Green Value: Green Buildings, Growing Assets
Green Building Canada: Doug McLenahan interview
A Business Case for Green Buildings in Canada
Benefits of Building Green
Industry Canada
Health and Productivity Gains from Better Indoor Environments
and their Implications for the U.S. Department of Energy
Why Go Green?

November 30, 2012 |

THE SHELL GAME: Constructing a building’s exterior for optimum performance

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figure 1Once you’ve analyzed the weather and the landscape around a building, your next line of defense towards making its indoor spaces economically comfortable every hour of the year is insulating its lowest floor, outer walls, and roof: what is known as the building envelope. This cutaneous construction may contain three kinds of insulation:

  • Batts – fluffy masses of spun glass that are fitted into voids in the construction.
  • Sheets – lightweight rigid sheets such as styrofoam and urethane that are fastened to walls and roofs and laid under concrete slabs.
  • Fills – lightweight granules or foams that are usually poured or sprayed into construction voids.

A big question with insulation is how thick should it be? Before speculating on the answer, let’s state some facts:

  • Insulation is a one-time cost that reduces a lifetime cost.
  • A prevailing myth in building construction is that every added inch of insulation is slightly less effective and after perhaps 6 or 8 inches or so you reach a point of no return where any further thickness won’t pay for itself. Not true. First, the point of no return is more like 20 inches. Second, the tipping point will not occur at a conceptual “added inch of insulation” but where the accumulating insulation suddenly requires a different and costlier construction to hold it. Due to continuing rises in energy prices, we will soon need to put many more inches of insulation in today’s building envelopes, and this will require new methods of construction.
  • The greater the temperature difference between the inside and outside of a building, the faster the heat flows through the building envelope (inward in hot weather, outward in cold); while the thicker the insulation in the envelope, the slower the heat flows.

Dealing with water

But all the above facts are befuddled by five little letters: water. Here’s the problem. Air contains a certain amount of water, usually as a vapour suspended in the air, measured as humidity. If the temperature of air goes down, its humidity goes up, until it reaches 100 per cent. If the temperature keeps going down, the water begins to drop out of the air because it can’t hold any more, and this moisture deposits on nearby surfaces.

Now when heat flows through an exterior wall wherever there are any seams, cracks, and pores in the construction, part of the migrating heat is carried through these openings by the air which, remember, also contains water. As the air flows through the wall and its temperature lowers, the air cools and its humidity rises until it reaches 100 per cent; then the water begins to drop out of the air and deposit on the wall’s construction. In the old days when energy was cheap and nobody thought much about insulation, all the air flowing through the envelope not only deposited moisture in the construction as the air cooled, the flowing air also carried away the deposited moisture.

But during the energy crisis of the late 70s, somebody got the bright idea that the way to stop a lot of heat escaping from a building in winter was to wrap it in an airtight membrane known as a vapour barrier. This stopped the heat flowing with the air—but it also stopped any flowing air from carrying away the deposited moisture. If this water cannot escape, it will rot the wood, rust the nails, dampen the batt insulation which ruins its ability to insulate, and act as cajun seasoning to a host of moulds, mildews, carpenter ants, and termites that love the nourishment of lignin—until after a few years a building’s outer construction will begin to stink, look awful, and fall apart all at the same time. In this respect we’re like B’rer Rabbit and the tar baby: de more we try to get unstuck-up, de more stucker-up we get!

If the shell of a building you live or work in is clad in Tyvek or one of its filmy kin, it is likely rotting around you right now and you don’t even know it yet. As the price of fossil fuels continues to rise and buildings continue to be clad in moisture-trapping vapour barriers, this situation has become perhaps the most insidious economic issue confronting American buildings today. Hear what Joseph Lstiburek, Ph.D., says of these thermodynamics:

Less energy flow (i.e. heat) from the inside to the outside means the materials on the outside of the building are colder in the winter. The colder the materials on the outside of the building become, the wetter they become and the wetter they stay. This is not good. Think of it this way. For every 100 units of energy you save on the efficiency and on the cooling side, you will need to give back about 20 units of energy to be dry. You are still 80 units ahead. The problem is that if you are greedy and want the entire 100 units, your building fails and your occupants become uncomfortable.

The insulation cage

insulation cage

Figure 2 – insulation cage

Is there any way to notably reduce the heat flowing through a building envelope without trapping moisture in it? There is! It is the insulation cage, a wall construction that contains thick insulation, allows enough air to flow through the construction and carry away any deposited moisture, and is relatively easy and economical to build. Its construction appears in figure 2. This 12-inch thick thermal armour has two 2×4-inch stud walls, each 3.5 inches thick, with a 5-inch airspace between—and no water-trapping vapour barrier around it. The outer and inner stud walls are built separately (the studs of each should align); and since each wall is light they can be built quickly. This was a major problem with the 12-inch superinsulated walls developed in the late 1970s: each took a huge amount of labour to build. I know, because I built one once—and Lord, I never spent so much time doing so little good. I found that while three men could easily raise a sixteen foot length of 2×4 stud framing with a window in it, the same three men could barely raise a six-foot length of 2×12 nominal stud framing with a window in it because it was so much heavier. The logistics of this are as follows: If you can lift 100 pounds and you need to lift 90 pounds (i.e. raise a 4-inch wall) you can do it; but if you need to lift 270 pounds (i.e. raise a 12-inch wall) you can’t do it and you must find another way to get the job done; but if you need to lift 90 pounds twice (i.e. raise two 4-inch walls), you can do it. This is why the insulation cage is easy to build, because it is not one heavy 12-inch wall so much as it is two light 4-inch walls.

The insulation cage has another big thermal advantage: the 5 inches between the two stud walls eliminates another heat loss known as perimeter heat flow. In standard stud framing, heat conducts through the studs between the insulation and the plates along the wall’s tops and bottoms; and since heat conducts through wood about four times faster than through fiberglass batts, nearly 40 percent of all the heat flowing through standard stud framing flows through the pieces of wood between, above, and below the insulation. This doesn’t happen in the insulation cage. As a result, only three-tenths as much heat flows through this construction as through a normal 6-inch stud wall. This means every thousand dollars of heating bills out of your pocket becomes three hundred dollars!

The insulation cage has other advantages that every carpenter will appreciate. The 2-inch-nominal cap plate normally nailed on top of the two stud walls to hold them together is replaced by a 12-inch-wide strip of £-inch plywood which alone has five advantages:

  1. The plywood is lighter and easier to cut than a 2×12.
  2. The plywood’s laminated 3/4-inch thickness is stronger laterally than a 2×12 is across the grain.
  3. A 3/4-inch plywood cap won’t shrink vertically over time as will most 2-inch nominal lumber.
  4. Four 12-inch wide pieces of plywood can be cut from one 48-inch wide sheet with no waste.
  5. Where walls meet at 90-degree corners and tee intersections, the plywood can be cut into L and T shapes that will make these junctions so rigid they won’t budge if you bump a truck into them.

As for the five-inch airspace between the two walls, it alone has four construction advantages:

  1. The space dampens noise transmission through the walls.
  2. It makes the walls more impervious to fire because half the wood is 5 inches from the other half and the batts between them won’t burn.
  3. The space allows electricians to lay the wall’s wiring on the floor between the two walls without wasting time drilling holes in every stud which also weakens them and without wasting more time pulling the wires through the studs which also can damage the wire’s cladding.
  4. Electric outlets mounted in the inner stud walls will no longer be notorious infiltrators of air because the boxes’ backs are shrouded with several inches of insulation.

How to build an insulation cage

  1. Build the outer 2×4 stud wall including its sheathing as it has always been done, but leave off the cap plate.
  2. Build the inner stud wall as you built the outer one. The studs in the two walls should align. With this framing nobody needs to learn any new construction techniques or how to use any new tools.
  3. Nail the 3/4-inch plywood cap plates onto the two walls.
  4. Fit two layers of batt insulation between the studs as follows. (1) fit 10-inch nominal batts (actual thickness = 9 1/2 inches) all the way in between each pair of double studs and staple the batts’ paper flanges along the back edges of the inner studs. (2) fit 4-inch nominal batts (actual thickness = 3 1/2 inches) in front of each 10-inch batt—to create a snug 13-in-12 inches of superinsulation. The slightly compressed batts will slow heat flow better because they eliminate airspaces that often remain around their corners in standard installations.
  5. Apply all interior and exterior finishes as with normal framing—except for those awful vapour barriers. Instead, cover the plywood sheathing with easy-to-apply tarpaper, which protects the framing from rain and allows it to breathe through its seams. Tarpaper also costs about 4¢ per square foot compared to 11¢ for Tyvek.

Not only is the insulation cage economical to build, thermally superior, and impervious to rot, it is stronger than any 2×6 framing. I wouldn’t wish this on anyone, but if a tornado swept through a neighbourhood of houses framed with insulation cages, more homes would be standing afterwards.

Another advantage of the insulation cage is that instead of mounting baseboard heating units against a floor’s exterior walls where some of the heat will escape through the unit’s backs directly outdoors, the units can be mounted against interior walls where the heat escaping out the units’ backs will remain indoors. Then your energy bills will be another ten per cent or so less. Today’s baseboard heaters are located around a floor’s perimeter because then the heat spreads evenly from one side of the building to the other; but if the cage holds in the heat three times better, the heat between the walls will spread more evenly and it will make much less difference if the heaters are centrally located.

Finally the cage not only eliminates moisture damage and lowers heating bills when heat flows outward through the building envelope in cold weather, it also eliminates moisture damage and lowers cooling bills when heat flows inward in warm weather—because the thermodynamics of one is the reverse of the other.
In wood framing, some say the studs should be 24 inches apart instead of 16. Unlike what the 16/24 ratio implies, you will not reduce the number of studs in the walls by one-third because the reduction occurs only between the wall’s openings and its corners. In a typical 12-foot-long stud wall with a door or window, you will rarely save more than two studs. At the same time the wider spacing makes exterior and interior finishes flimsier and it offers less support for cabinets, shelves, and large pictures installed inside. Altogether the wider spacing is a fine example of being penny-wise and pound-foolish.

Another popular idea is to clad a building with several inches of rigid insulation. Though this insulation is thermally strong, it has a few weaknesses:

  • It is difficult to fasten exterior finishes to the insulation and the insulation to the wall inside. This is typically done by attaching a metal clip to the side of a furring strip to which the exterior finish is nailed, then inserting a long steel screw (up to 14 inches if needed) through the clip and the layers of foam into a stud behind, as sketched in figure 2. To secure this connection you must drive the screw blindly through all those layers of insulation into the stud’s centre—not to either side where it would often split the stud’s edge and form a weak connection. This is a mighty narrow target for a woodbutcher to hit 49 out of 50 times—unless the targets are timbers.
  • Since steel is a poor insulator, each long screw acts like a thermal soda straw that sucks heat through it several hundred times faster than through the surrounding foam insulation. In this construction this conductance can amount to a significant perimeter heat loss.
  • Some rigid foams burn and emit large volumes of deadly gas. Before using this insulation, take a tiny chunk outside, light it and take a whiff of the fumes. Then decide if you would like to enclose you and your loved ones and/or business colleagues in this material.

Rigid insulation does have a place in building construction. It is between an outer and inner masonry wall and under concrete floors. There the thermal barrier won’t burn, no perimeter heat will flow through it, and nothing can rot.

Insulation cage or spray-in foam?

The insulation cage also indicates the limitations of another insulation that has been promoted a lot these days: spray-in foam. This product’s installers—the gun guys—have to wear oxygen respirators and head-to-toe protective suits because as they apply the foam, expanding droplets fly into the air and stick to light fixtures, electrical outlets, floor registers, doors, windows, tools laying around—you name it. In one installation the owner decided to photograph the work for his records; the goo flying from the guns got in his hair and ruined his camera. Yet a knowledgeable person must monitor this work because:

  1. The gun guys must mix the foam’s ingredients precisely because off-ratio mixes have considerably lower R-values (R-value is a measure of heat flow through a material: the higher the R-value the better the material insulates).
  2. Installations of more than two inches require several passes because thicker applications will release too much heat in the foam and can char it.
  3. If too much foam is applied between the studs, the excess must be laboriously trimmed from the studs’ inner faces or the walls’ interior finishes will look lumpy.
  4. If too little foam is applied you won’t get what you paid for. If you decide to use this material, insist that the gun guys bring along an extra uniform for you or another knowledgeable person to put on before the motes begin to fly.

This work also requires far more electricity to operate the drum warmers, proportioning machines, and foam pumps than it takes a few labourers to install batt insulation with power staplers; and if the installation is off-grid, it requires renting a trailer-mounted generator for the day. Old buildings have another problem. If the foam is sprayed through holes drilled in the interior finish (the usual method, rather than removing the finishes to expose the framing), it is virtually impossible to fill every void between the studs below the wires running between the electrical outlets—and every little hole in the insulation drains heat the way the little hole in the bottom of a sink drains all the water.

Using spray-in foams can also create bureaucratic hassles. Some manufacturers prohibit applying foams at more than certain thicknesses, which makes some code authorities prohibit the same; then there go the advantages of superinsulation. Some building inspectors also demand a letter from an engineer stating that the framing is strong enough to support the foam (never heard this done with cottony batts); some officials have voiced fire and health safety concerns because most foams support combustion and emit toxic gases; and some foams void shingle and roof venting warranties. To top it off, for all these headaches you often pay two or three times what you’d pay for semi-skilled labourers to install fiberglass batts.

Insulation cages for old buildings

Insulation cages are great for new buildings. What about old ones? This is a serious consideration, because there is no way all the king’s contractors and all the king’s crews can tear down all the millions of existing energy-wasteful buildings in this nation and replace them with new ones that consume a third as much energy. So if we are to solve the energy crisis, we must find ways to make existing buildings energy-efficient. But how?

What other solution is there than to thicken the existing exterior walls? With not just six inches of insulation, but twelve inches. This can be done in three ways:

  1. Tear down the existing walls and replace them with thicker ones.
  2. Thicken the existing walls from the outside.
  3. Thicken the existing walls from the inside. The first option requires more work and more disruption of the building’s use during the work. The second, being outdoors, would be affected by bad weather. So let’s home in on the third.
Framing for rigid insulation

Figure 3 – Framing for rigid insulation

If a building has lots of wasted space inside which is made more efficient as described in chapter three, you would probably have plenty of room around the inside of the exterior walls to build a second wall up to a foot thick and fill it with as much insulation. This work could be done indoors one room at a time, so occupants could still use most of the building. One kind of building today would be perfect for this. McMansions! The bloated spaces in these wigwams of modern wasteful society could easily endure a little liposuction inside their skins, especially if the remaining interior becomes more sveltely comfortable. This construction could be performed as sketched in figure 3, as follows:

  1. Remove the interior finish from the exterior walls and the floors and ceilings 9 1/2 inches back in from the walls.
  2. Fit pieces of batt insulation into the voids between the ceiling framing above the wall and the floor framing below for 16 inches in from the wall.
  3. Erect a second 2×4 stud wall 9 1/2 inches in from the existing wall.
  4. Insert 10-inch thick batt insulation into the new wall.
  5. Refinish the new wall same as the old, according to taste.

As usual, all this isn’t as simple as this glib description suggests. For one thing, you’ll have to remove the electrical outlets and wiring in the old walls and reinstall them in the new ones (but any electrician can do this). A more serious matter is if any closets, kitchen cabinets, or plumbing fixtures are against exterior walls. You’ll probably have to tear them out and relocate them further indoors. Also, framing the second wall around existing windows and exterior doors would require a skilled carpenter.

As for thickening a building’s exterior walls from the outside, this may be a better choice if the spaces inside are already compactly designed. One way to do this is to:

  1. Strip the exterior finish from the outer wall but leave the sheathing since it helps support the building.
  2. Remove any Tyvek or similar vapour barrier.
  3. Drill 3/4-inch holes 16 inches apart vertically in the sheathing between each pair of studs. These “nostrils” will help the wall breathe.
  4. Build a 9 1/2 inch ledge at the wall’s base just below the first floor. This can be done several ways depending on the existing construction.
  5. Along the ledge’s outer edge, frame a 2×4 stud wall for each floor up to its ceiling or the roof’s eave.
  6. Insert 10-inch batts from the outside between the studs.
  7. Sheath the studs, add the exterior finish, clean up, and you’re done.
Superinsulating old roof eaves

Figure 4 – Superinsulating old roof eaves

What about roofs? If a building has a wood truss roof, you can lay thick batts on the existing insulation in the attic to create 16 full inches of insulation. But if the roof has short eaves, a problem may occur where the trusses’ ends meet the top of the exterior wall and the eave of the roof. At this triple intersection a constriction would prevent installing the full depth of insulation. One solution appears in figure 4, whose construction would proceed as follows:

  1. Remove the lowest 2 or 3 feet of roofing and its sheathing up from the roof’s eave.
  2. Mount on each exposed rafter or truss strut a triangular cleat whose outer edge is high enough to allow a roof vent to fit above the new insulation to be laid in the attic. Each cleat should be the same thickness as the strut or rafter it rides on and is held in place by small 3/8-inch plywood gussets nailed to its sides.
  3. Resheath and reshingle the roof the same as before.

Now all this work may look too difficult to think of doing it yourself. It may even look too difficult to think of anyone doing it. But any carpenter worth his framing square can do it. Besides, think of all the money you’ll save someday when energy prices are five times what they are now. Then, remembering that ancient day when you haltingly took these pages to a local builder, you’ll look back at what you did and smile.

Shingle or shake?

Thickening existing interior walls from indoors

Figure 5 – Thickening existing interior walls from indoors

A note on asphalt shingles. These are usually replaced every ten to fifteen years and they create 10 million tons of waste per year. Enter Enviroshakes and Panelshakes. Made from waste wood fibres, old tires,used milk jugs and other recycled products, these shingles have a brownish-gray hue that weathers to a silver-gray similar to cedar shakes. They are easy to install, are maintenance-free, require no added treatment or preservatives, and are fire-, mould-, and insect-resistant. They claim to be competitively priced and last more than 50 years. To learn more about this product, visit www.enviroshake.com.

Looking forward

As the decades go by and energy prices keep rising, these constructions will become increasingly practical. In fact, if I wanted to stack my chips on the one “dark horse” idea in this book that presently seems the most far-fetched but fifty years from now will prove to be the most sensible, thickening existing building envelopes would be it. You may also think that thickening these constructions as described above will be a lot of trouble. And it will be. In fact, it might be about a third as much trouble as searching for a better place to live, moving out of your old abode, moving into your new one, and trying to sell your old energy guzzler to a less gullible public.

As if the past can point a quicker path to the future: out in south-central Colorado, at 8,000 feet above sea level where temperatures soar above a hundred degrees in summer and plunge below minus thirty in winter, is a town with a frontier command post of the same name: Fort Garland. Built in 1858 to garrison 100 soldiers commanded by Kit Carson, this fort (which today is a historical landmark that is open to visitors) has several long buildings whose thick exterior walls retard heat flow in this area of climatic extremes. How thick are these walls? Twenty-four inches. In the corner of each room is a little fireplace to keep the occupants toasty warm. Each windowsill is so wide one can sit on it and enjoy a view of several fourteen-thousand-foot peaks stabbing the azure a few miles away. Those oldtimers sure knew what they were doing well over a century ago. Certainly we can do as well in the near future.

 


 

After graduating from the Cornell School of Architecture in 1964, Robert Brown Butler has worked as a carpenter, contractor, and registered architect. Through the years Mr. Butler has received a variety of honors for his creative work. He is the author of The Ecological House, which introduced many ideas that are further advanced in this volume, among other books.This excerpt reprinted with permission from Architecture Laid Bare!: In Shades of Green, by Robert Brown Butler. © 2012, Robert Brown Butler.

November 15, 2012 |

2030 CHALLENGE: Raising the bar for the building industry

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Globally, about one-quarter of greenhouse gas emissions are building related. And that figure is even higher in developed nations. With this massive opportunity to cut GHGs, the non-profit Architecture 2030 has created the 2030 Challenge, an initiative that asks the global architecture and building communities to go carbon neutral by 2030.

The Challenge specifically targets new buildings, developments and major renovations, asking them to reduce energy consumption and fossil fuel/GHG emissions to 60 per cent below the regional or country standard for that specific type of building. That figure increases to 70 per cent in 2015, 80 per cent in 2020, 90 per cent in 2025, ending at carbon neutral in 2030.

Architecture 2030 suggests these reductions come from sustainable building and design practices as well as generating renewable power on-site. Purchasing renewable energy is also an option, but one that’s seen as a last resort with a 20 per cent cap being placed on it.

Existing developments are challenged to reduce their GHG emissions as well. Under this plan they would be expected to reduce fossil-fuel use for buildings, CO2 from transportation and water production by 10 per cent, gradually increasing to 50 per cent in 2030.

The Challenge has gained some serious backers in the few years since its inception. The American Institute of Architects, with its 80,000 members, have accepted the Challenge. As have the U.S. Conference of Mayors, the U.S. Green Building Council and a number of other architecture, building and environmental groups as well as many businesses and universities.

In practice, government has given the Challenge quite a boost. The EPA now uses the 2030 Challenge’s targets in their web-based calculator. As of December 2007, the Energy Independence and Security Act made it mandatory for all new construction and major renovation of federal buildings to adhere to the standards of the 2030 Challenge. State, city and county governments have also issued their own initiatives in line with the Challenge.

A Design Futures Council poll found that in the U.S. approximately 40 per cent of all architecture firms have adopted the Challenge. And 73 per cent of the 30 largest architecture and engineering firms in the country have also agreed to this initiative. These large firms operate multinationally and the hope is that they will spread the ideals of the 2030 Challenge to the projects they work on.

As the adoption and implementation rate of the 2030 Challenge picks up, the market for green building and related materials and renewable energy systems expands. In this way the building industry is building a way out of greenhouse gas emissions and creating a more sustainable built environment. A much needed change for a highly consumptive industry.

For more information visit Architecture 2030.

October 20, 2012 |

CONSTRUCTION DUST: A growing problem for the industry to address [infographic]

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When dust and debris from construction sites get blown into the air they can cause respiratory problems and property damage. It’s a big problem, particularly in populated cities with numerous construction projects. Wherever possible, prefab homes could be an answer to reducing construction dust. Do you think green building can minimize the problem of construction dust? Add your thoughts below.

Construction Dust

 

October 8, 2012 |

10 green architecture improvements for homes and offices

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Iceland house

1. Working with contractors – Know the vocabulary. You’ll have a better chance of negotiating successfully with builders if you know about breaker boxes, water pressure tanks, load-bearing walls, and other such construction anatomy. A good way to learn is to get a book on construction and trace your electrical, plumbing, and other utility lines from where they enter the building to their points of use. Also, when on a construction site, wear a hard hat and work boots. Aside from being safer you’ll get to see more of the work, and you’ll be treated like an overseer and not an intruder.

2. Light bulbs – Compact fluorescent lights (CFLs) are not better than incandescent lights when it’s less than 60 degrees outdoors, when they’re turned on and off a lot, or when they’re on less than 15 minutes. Also, their light is worse and the energy they save is tiny compared to—only one example—the energy that your house throws out its windows at night (better to stack your chips on lowering this). But here’s a light that uses no energy at all: luminous escape route trim. Use photo luminescent tape to your baseboards and you’ll always know where you are in the dark.

3. Solar panels anyone? – On a sunny day around 9:30 a.m. climb onto your roof and see if the sun shines on it. Repeat this around 3:30 p.m.  Does the sun still shine on the shingles? Did it do so every hour in between? If you cannot remove the trees or nearby buildings or hills that obstruct the sun during these hours, do not install solar panels. Exception: south facades or terrain close by that receives lots of sun during the day.

5. Fireplaces – A fire in a conventional fireplace is only 20 per cent efficient. Worse, when its hearth is cold lots of fossil fuel heat sucks up the flue unless you reach way under the mantle and close the sooty damper. Better: A fireplace insert that can burn logs and paper trash, has intake and outflow vents at the bottom and top (you shouldn’t need a circulating blower), has an easily operable damper, and sports large glass doors so you can enjoy the dancing flames. A fireplace insert is 50–75 per cent efficient and easier to operate.4. Buy a backup generator? Why pay $950 for a cubic yard of materials that ravaged the environment in its making, requires more money and extreme care to install (people get killed when they don’t do this right), and needs monthly testing? Cheaper, simpler, and safer: For those rare occasions when the power fails create a power-outage kit that includes a dozen candles with holders, half a dozen flashlights with extra batteries, and several large buckets (when the power fails fill them at the nearest creek or lake, cistern the water in your bathtub, and use it for flushing toilets and rinsing)—then “go camping” with the kids and canned foods before your fireplace.

Iceland house

6. Drainage – Whether your house stands on level or sloping terrain, the ground extending from its foundation should be graded at least 1/2 inch per foot downhill for 10 feet in every direction. This contouring—even if it takes dynamite and backhoes—is not money spent but money saved. Tip of the day: always locate a house on convex, not concave, terrain.

7. Mould – If mold appears inside your exterior walls or on your exterior siding, you may be suffering from the biggest mistake made in wood construction today: airtight envelopes. Airtight vapour barriers keep moisture-laden air from migrating through the wood framing, then the trapped moisture rots the wood. Contrary to what many “experts” say today, the solution is NOT tighter construction—because you can NEVER get rid of all the moisture and wood needs to “breathe” to keep from rotting. The only way out of this dilemma is radical surgery: Choice #1: Strip the siding, replace the Tyvek with tarpaper that allows air to infiltrate between its seams, and install new siding. Choice #2: While doing choice #1, thicken the exterior walls, either from the inside or outside, with more insulated construction. Save your house first and worry about your energy bills later.

8. Furnitecture – This is efficient furniture—items like bureaubeds, shoulder-high walls, and long desk counters with lots of shelves above and drawers below. Replacing the usual fat furniture with these compact items not only will make less indoor space more useful, it can create enough room around the inside of your exterior walls to add a second wall of insulation. This is the real secret to making your home or workplace more energy-efficient in the future.

9. Efficient indoor spaces – By removing useless corners, unused crannies, gun barrel hallways, seas of circulation around islands of furniture, and other chubby cubic footage indoors, not only will you be more comfortable in less space, you may have enough room in your home to install an office, have an exercise area (instead of driving to a dues-paying health club), and store more belongings (rather than rent a storage unit miles away). One of many clever ploys: Convert the usual wasted space between a row of studs into a hallway library or similar shelving. This can be done almost anywhere indoors.

10. Fire safety – When a fire erupts indoors a hot region exists at the flames—the fire zone—and areas nearby fill with toxic gases—the smoke zone. Both are deadly. Along with installing smoke detectors, fire extinguishers, and fire exit signs, fit one sink faucet on each floor with spigot threads so you can screw a hose onto it. Outdoors, on two opposite facades mount spigots with frost proof sill cocks (the water in them won’t freeze in cold weather) and beside them mount hose racks with 75 feet of hose.


 

Robert Brown Butler is the author of seven books on architecture, including his new book titled Architecture Laid Bare! In the new book Architect Laid Bare! In Shades of Green, veteran architect Robert Brown Butler focuses on taking the mystery out of the challenges of green architecture. In this highly readable and comprehensive book, he explains the newest and best ideas for creating each element of a modern building’s design and construction. For more information visit www.architecturelaidbare.com.

photo courtesy criscris1 (sxc.hu)

October 6, 2012 |

WHAT HOME BUYERS WANT: 4 things that today’s buyers are looking for

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It’s a buyers’ market, and here are the four things that today’s buyers are looking for:

Modest floor plans

So long, McMansions! Surveys show that Americans are considering smaller homes.

Organization and comfort

A National Association of Builders survey identified the top 10 amenities buyers are looking for in new home construction:

– Programmable thermostat
– Great room
– Insulated front door
– Low-E windows
– Linen closet
– Walk-in closet in the master bedroom
– Separate shower and tub in the master bedroom
– Energy-efficient appliances and lighting
– 9-foot-plus ceilings on the first floor
– Laundry room

Smaller price tags

Today, more buyers seek homes that cost less than $200,000

Improved energy efficiency

Homebuyers want to create a smaller footprint and save on energy bills. They want homes with greener features like: an energy-efficient heating and A/C system, Energy Star appliances, an efficient design, more natural light, extra insulation in the attic, other insulation, such as panels or foam.

Green homes made up 17 per cent of the overall residential construction market in 2011 in the U.S. By 2016 experts predict that number could climb to 38 per cent.

September 5, 2012 |

RESOURCE-EFFICIENT REMODELLING: Repurpose what you can to save money and materials

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Home restorationIf you’re thinking that building or remodelling your home in an eco-friendly manner means spending more, think again. In fact, I urge architects, designers and builders—not to mention the homeowners who hire them—that building green doesn’t necessarily mean spending a lot of green.

“Green” is more than buying the newest thing. It’s also learning how to use what we already have.

For example, I worked on a project where we had to get a home ready to go on the market. The kitchen was hopelessly dated (think the kitchen in the Brady Bunch), but the homeowner didn’t have a bottomless bucket of money for the typical kitchen upgrade. No one could see any option other than ripping out the 1970’s dark cabinets and starting over. Cost for the least expensive cabinetry from the big box store was over $10,000.

But when I compared the inherent quality of what we had versus the quality of the new products (as opposed to simply the visual appearance), I realized that older was better. The old cabinets were solid wood, and the doors were straight, had a nice weight, and closed with a satisfying “chunk.”

I suggested that we do a “soft demo” of the existing cabinets, where removal is done carefully, reconfigure the boxes (because cabinets are a series of modular boxes attached to one another), paint in a lighter colour and install new hardware.

We kept the old cabinetry out of the landfill, avoided consumption of all the raw materials and energy to produce the new product, and the homeowner saved $6,500.

In another project, we added a second storey to a home without consigning the existing first floor to the dumpster. The standard procedure when adding a second floor calls for such significant upgrades to the existing framing and shear wall (particularly in California with seismic requirements) that the existing first floor is virtually torn down. Instead, we devised a system with the structural engineer to strategically imbed structural steel beams at various points around the perimeter of the existing residence to carry the load of the second floor.

Again, we kept the existing materials out of the landfill, didn’t consume new product, saved money, and most importantly, preserved old-growth finishes in the circa 1915 home.

When examining energy savings, look to the past. For example, how were homes designed before we relied on heating or air conditioning? Wide eaves, shaded porches, higher ceilings and transom windows all help to naturally cool a house. Placing windows properly is vital for good cross-ventilation for cooling, and to capture daylight to reduce the need for artificial light during the day.

While swapping standard light bulbs for compact fluorescent lamps (CFLs) and making sure empty water bottles go in the recycling bin are things all of us can do, “living green” can extend into an even more fundamental part of our lives—our homes.

The “greenest” building is the one that’s already built. So focus on what’s right, save and repurpose what you can, and scrutinize everything before you toss it in the dumpster. Find architects and contractors who can think beyond the standard paradigm of, “It’s cheaper to tear it out and build new.”

 


Anne Goepel is vice president of Drake Construction. In addition to working closely with clients and architects, she schedules subcontractors, manages crews, and ensures that all projects meet the stringent criteria for which Drake Construction is known. Visit www.drakeconstructionla.com.

This article was originally published in Living Green Magazine.

August 27, 2012 |

SMALL AND SUSTAINABLE: Review of small and tiny home kits, plans and finished homes

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Small and tiny homes

I like tiny homes—homes that are generally no larger than about 500 square feet. In fact, I lived in a 264 square foot home in the mountains of Taos, NM, for five years. And yes, I had an indoor toilet.

And I like the idea of building my own little green home. So, I got online and gathered some information about small, kit-based homes that offer lots of green features. The following information is by no means all-inclusive, and is not an endorsement for any product. But hopefully it will get you thinking—as it did me.

Here are a couple companies who design and build small homes and provide kits and/or plans.

Shelter-Kit Green Homes and Cabins

Known for over 40 years for their great quality, Shelter-Kit’s small buildings are versatile, aesthetically pleasing, and come with detailed, easy-to-understand instructions. Best known for their barns, the company offers an impressive line of green homes and small cabins, starting at 144 square feet.

They’re all designed for assembly by people with no prior building experience. They ship anywhere, and even help you obtain a building permit. Every order is considered custom, and so customer support continues even beyond construction. No on-site finish is required, and each building incorporates approved bio-based materials and energy-efficiency practices. Visit www.shelter-kit.com.

Tumbleweed Tiny Houses

Starting at just 89 square feet, these homes are smaller than many people’s closets. Their greenness comes primarily in their size and the resulting impact on the environment, although you can buy plans and substitute greener construction materials. The prices for a completed home seem high, but Tumbleweed offers ready-to-build kits for less than half the price. They also offer building workshops across the country.

Their smallest homes are designed to fit on a trailer, making them a travel trailer, not a home. This means—wink, wink—that no building permit is needed, and you can park it anywhere an RV is permitted. Visit www.tumbleweedhouses.com.

Tiny Green Cabins

This company has the smallest of the small buildings—from 48 to 252 square feet. They may also be the greenest—using green-certified materials, reclaimed products, and recycled materials. Tiny Green Cabins also has a toxic free cabin, with insulation made from recycled blue jeans. Even the floors are insulated. They have plans and completed homes, but not kits. www.tinygreencabins.com.

 

 

Leap Adaptive’s Hummingbird Homes

Leap Adaptive specialize in providing the “the most advanced online green home plans available.” Two of their plans—Hummingbird at 480 square feet, and Hummingbird II at 860 feet and 2 bedrooms—offer the leading edge in green home design that is functional and beautiful. Their designs offer a modern and pragmatic green approach that can be built at an affordable price.

The H2—the Hummingbird not the Hummer—integrates passive solar electrical generation with a highly efficient thermal mass design. The design incorporates scrap construction materials to reduce landfill waste. It comes as a complete home or a kit. Take a look at www.leapadaptive.com.

 Tiny Texas Houses

I didn’t know anything was small in Texas, but these small homes have a lot of character and are made with hardwood trees the company harvests as well as with salvaged materials. Check out www.tinytexashouses.com.

Planning Resources

 


by Richard Kujawski

Republished with permission from Living Green Magazine.

August 21, 2012 |
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