Air Traffic Control

What can both keep you warm and cool you off? What is invisible and untouchable, but can carry water, germs, noise and odors? What can both improve and impact your health? It is the “ghost” in the room – AIR.

No other building element is as elusive as air, yet so important to the long term performance of a building. Unlike solid, stationary building components, air has no permanent residence and prefers to float about like an undiscerning host, carrying moisture or dog dander or cigarette smoke with no moral compulsions. Mostly, air transports heat – generally in the opposite direction of our comfort levels. This air flow can account for 30% of the heat loss across the walls of even well-insulated modern home. (Buildingscience.com). Another 20% thermal transfer comes from the air leakage through windows and doors. And air leakage through ducted distribution systems can penalize the performance of HVAC systems by 30%.

Of equal concern is the vapor migration carried deep into the wall cavities by the airflow. With fluctuating temperatures, this moisture can condense out of the air and transfer to water absorbent materials - wood, paper on drywall, many types of insulation. Moisture, heat and food is the perfect recipe for mildew, mold and rot.

And then there are issues of air quality, air equalization, air-borne noise…

What to do? Start by putting air on the blueprint. Identify the boundary of indoor to outdoor air, identify the intended flow and filtration of the indoor air, and then build accordingly. An air barrier should be continuous, and be durable enough to meet the intended service life of the home. Well documented air barrier methods include the airtight drywall approach (ADA), and the exterior building wraps developed in the cold climates (PERSIST or REMOTE). Another solution is to build with materials which are air barriers by definition, such as poured-in-place concrete.

As a good back-up plan would be to use materials which are NOT susceptible to moisture or mold problems. Even steel can rust. So now I tip my hand and point to building systems such as Insulating Concrete Forms (ICFs). The EPS foam does not absorb moisture, and neither it nor concrete rots or molds.

But lest you ICF folks out there get too smug, let me point to the “Capillary Break” blog (04/06/10), the need to address the air loss through windows/ doors/ HVAC ducting, and the Achilles heel of ICF construction – the connection of the walls to the ceiling/ roof. There is an equal need to address the right-sizing of the HVAC for control of interior humidity. But these are also part of any building requirements, and most certainly building the exterior walls with ICFs is a solid start to a good “Air Force.”

Lost There, Felt Here

Oil continues to spill in the Gulf with an equal gushing forth of accusations. Politicos use this crisis to deliver a few more punches to President Barack Obama. Tea party members proclaim the need for less government. Is this less of the government which approved tax and royalty relief to encourage oil drilling, as part of the 2005 Energy Policy Act? Subsidies which made sense at $18 a barrel, yet continue even at today’s prices. Or is this less of the government which responded to the very inability of private companies to accept responsibility for environmental safety, and created the Environmental Protection Agency (EPA) to protect our air, water and environment.

Point fingers just doesn’t work in our world anymore. “Lost there, felt here.” This simple credo of Conservation International reminds us that the oil will not only impact the supply of shrimp, or the cleanliness of the beaches, but it will destroy large areas of eco-system and the livelihood of the people who depend on them. Where will these people go? There are more refugees displaced by environmental disasters than by war, and experts have projected that number will double within the next five years to over 50 million. These are the fishermen who will soon have to join the refugees from Katrina in the ranks of the unemployed. Canada has taken on refugees from Bangladesh and Haiti, and all wealthy nations will share in the financial responsibility of the displacement of people, and the decimation of previously bountiful lands turned to desert, or flooded by rising seas.

The oil continues to flow, because we continue to consume it. Responsibility for the environment and energy solutions must begin at the local level. In Europe, the town of Tubingen has demonstrated that this is also good economic and social policy. The mayor, who proudly rides a bicycle to work, has set a goal of reducing green house gas emissions by 10 percent by 2010, and by 70 percent by 2020. Solar panels installation has doubled; old heating systems are being replaced with energy efficient heat pumps; a new housing development has been designed as a walkable community to reduce reliance on automobiles. These are citizen funded initiatives, with increasing participation at all levels. And Tubingen is not alone. In Germany, there are 100 cities that have declared their commitment to 100 percent renewable energy.

It is time to stop looking at Uncle Sam, and start looking in the mirror. What can we do in our own towns, our businesses, our own life patterns?

Sustaining Sustainability

Teaching a man to fish.. Just like one of the food aid programs in Haiti, run by locals who not only feed the masses, but also work on reforestation and restoration of agriculture. The goal is to restore Haiti to the state of food self-sufficiency which it once enjoyed. This program will be sustainable, even as the US donations shift to the next crisis.

And so it is with sustainable “green” building. Regardless of the level of good will or intent, sustainability measures must be able to stand on their own merit if they are to take a position in the mainstream. Look at what happened in the 70’s, when the oil crisis prompted a call for wearing sweaters. Energy savings from improved technologies was not distinguished from saved energy through reduced comfort.(Goldstein) Not surprising, when oil prices were again lowered, the consumer chose comfort over energy savings.

So green building needs to improve the bottom line and quality of life. Architecture 2030 proposes one such solution by rewarding energy efficient measures in new construction with lower interest mortgages. Homebuilders get a sales edge; homeowner get lower payments, lower utility bills, high comfort. Some power companies provide a solution by setting up a revolving fund to finance the installation of PV panels. As opposed to tax rebates, this funding mechanism is a self-supporting and makes PV panels affordable for more people than just those who can afford the upfront costs. (see blog “Solar Panels for All” 04/02/10).

This type of industry support will certainly help foster change, but widespread market transformation to durable and energy efficient construction must be cost-competitive to be sustainable.   I look to lean construction for hope. Combining the finest of integrated design and value engineering, lean construction adds a finely honed delivery system. Lean can enable green. And as lean principles promote continuous learning, more lean can continue to deliver more green.

Just as the Haitians are banding together to create solutions to their food needs, can the building industry and its partners collaborate on sustainable solutions to transform the building culture and build affordable net-zero buildings?

Greenwashing

As an old 70’s passive solar gal, I cast a bit of an cautious eye to the “greenwash” which has swept the nation and question the underlying intent. Just yesterday, I read a parallel opinion of veganism, which noted that the ethical argument about “inhumane” treatment of the animals in the food processing is a bit misplaced empathy in view of the fact that slaughterhouses have among the highest on-the-job injury rates of any profession. Are we likewise applying our “green building” efforts selectively?

Take Walmart, for example. Frequently praised for building more energy-efficient stores, using alternative fuel in its trucks and reducing packaging, Walmart is now urging suppliers to reduce 20 million metric tons of greenhouse gas emissions by 2015. Would these be the Chinese suppliers? I seem to remember that Sam Walton built his business on promises of American-made product, and I also remember the companies, towns, and PEOPLE whose lives were decimated when Walmart pulled the plug to move the business to China.

While their energy efficient measures are commendable, they also contribute positively to the bottom line. But how about some of the tougher decisions – like retrofitting existing big boxes to improve an existing community? And how do you account for the local businesses which are displaced when Walmart moves in, or the resulting low wages, part-time work, or low return investment to community. Is this green? Now Walmart is donating food. Why not just provide for their own employees?

On the other hand, look at the examples of Ben and Jerry’s, Patagonia, IceBreaker. Their mission statements include: linked prosperity, culture as energy, ethical manufacturing, transparent supply chain, cause the least harm to the environment. These are very economically viable, global companies who are helping the make the future livable, safe and just for everyone. They embody the vision of the CERES group, who introduced the vision of a world in which business and capital markets promote the well being of human society and the protection of the earth’s biological systems and resources.

I see the CERES version of green as the circular ripple when a drop hits the surface of a pool of water. The effort starts in-house, implementing measures which reduce waste, improve employee lives, and lessen the environmental footprint of the product. The next ripple is the interaction of this company with its surrounding, the neighborhood, the community. And so the impact of the company improves the surrounding spheres, not skipping over any, but recognizing their interconnectivity. Advancing Sustainable Prosperity.

Readers - I need your help. Who are the Ben& Jerry’s of the construction world? I am specifically interested in learning the stories of residential builders who have embraced the ripple effect of green. My PhD topic will be building on the lessons learned from these folks, with this blog as an opportunity to share knowledge. So - let me hear from you. Send me your own story, or links to other builders, websites, blogs. Let’s learn together.

Working with Repurpose

Recycling and Re-use. No one will argue the environmental benefit of extending the life cycle of a material. These days, one can proudly display the old doors, the salvaged beams, the repurposed old slate blackboards. But at what cost?

For my old house project, I had carefully saved the existing doors and even roamed the salvage yards looking for a match for the extra few I needed. But a few months ago, my builder and I ran through the math. It would actually cost about 30% more to use the existing doors than buy new ones. This had to do with the labor of stripping the hardware, getting the door panels sanded and repainted, and then having the door jambs built for them. I had even found a plantation shutter shop who had some down time after the holiday season and would sand and paint the door for $100. Having had my own crew do this same work, I knew this was a good price. But the cost difference was still significant.

This brought up an interesting dilemma and possible opportunity. I noticed that the LEED-H program offers more points opportunities for recycled materials, less for recycled, and even fewer for re-used on site. The amount of labor for materials is in reverse proportion to the points. Used material is rarely standard sizes, is difficult to match if there is not enough, and it often has to be restored, at considerable time and expense.

Homeowners doing their own remodel are the greatest users of “re-purposed” materials, as they are able to justify the expense of time as a labor of love, and mostly an expense which does not impact the pocketbook. Commercial construction may be able to work with large salvage items, though structural elements like beams run into issues of certifiable strengths.

One of the least explored areas of use is the contractor led remodel. Could the homeowner contribute labor or time? Could the contractor identify which materials could be sourced from Craigslist, along with a timeline and some specifications? What comes to mind is pulling nails from salvaged lumber, or sanding and painting old woodwork, looking for sinks, tiles, or flagstones. It would require a lot of communication, trust, and adjustment. A bit of re-purposing on everyone’s part.

Interoperability

We think of BIM tools in terms of interoperability – but what about people? What about building components? Trades? Skills? It is a lesson we learn from nature and history. No man is an island.

So why do we continue to train solar panel installers without offering some nod to the need to assess the structural strength of a building, or the electrical load of the house circuit? Or what about the concept of weatherizing first, and then adding renewable energy resources.

And weatherization. This is a series of actions which can lead to… reactions. Like increasing trapped humidity in an unventilated attic which leads to condensation. Or stale air, or back-drafting from combustible appliances. Where is the lesson in interoperability of building science.

Lest I rant the entire blog, let me ask for some hope and feedback. Are we moving as an industry toward increasing isolation of speciality and materials, or is there a push-back? I would like to think the trend of design/build is a hopeful sign. Or BIM - the tools which are pushing people back into the same room to learn to collaborate.

Today I met with a group of community colleges who are interested in increasing the interoperability of their sustainability curriculum. I see this as a hopeful sign. People working together, developing a curriculum to train people who know how to work together.

How does your world look through the lenses of interoperability? Where does your product interface with the rest of the building – and what impact does it have? Perhaps if we think back to those concentric circles, we can continue to connect ourselves to the next rings, and eventually fit the industry back into the greater, interconnected world in which we live.

Interoperability – it’s an attitude.

Looking at Windows

Windows are designed to be look through, but occasionally, we look at them.  What we see depends on our perspective.  Architects may see the design, building scientists will look for air or water leaks,  the cleaning staff will immediately assess the difficulty of reaching all the panes.  Windows are often the battleground for preservationists vs energy retrofits, with several myths promulgated by both camps.

Myth 1: Historical windows are always better.  According to the National Register of Historic Places, the minimum age for historical is 50 years.  In 1966, when the agency was established, this timeline would have referred to buildings from 1916 and earlier.  Windows would have been built out of solid heartwood, possibly designed with removable interior sash stops, allowing for full access for cleaning, repair or replacement.   However, a 50 yr old building also now includes the “mid-century” homes, some of which had single-pane aluminum crank-out windows.   One would be hard pressed to figure out anyway in which these would be better than a replacement energy efficient window.  

Myth 2: New windows are always worse. This referred to  vinyl and aluminum windows, which don’t have the longevity of wood, nor could they match the look.  However, the new pultruded fiberglass windows have a narrower profile similar to wood, can be purchased with exterior muntins to simulate divided lite panes, and very low heat conductivity.  From an environmental standpoint, fiberglass takes the least amount of energy to produce and has the longest life expectancy of any window frame material.  This provides an option which satisfies both historical integrity and energy concerns.


Debunking the myths, what is the best way to proceed?   Decided if the window style is an intrinsic part of the existing architectural design, or the intended design of the remodel.  Not every old building is historical or architecturally pleasing.  Can the windows be repaired or improved for air and water sealing?  (link to the retrofit of the Empire State Building) Existing fixed windows from the 60’s can often be left in place, supplemented by an additional fixed double pane on the interior.  Interior storms can provide the extra protection while retaining the historical exterior of operable windows. And if the decision is to replace new windows, spring for high quality, energy efficient, long service life.  Make sure they are installed with proper flashing and window pans.  This is a big investment which you don’t want to have to revisit in 10 years time.   This is an investment not only in energy savings, but comfort, ease of maintenance, and functionality.  What you see is what you get.

Achilles Heel

Everyone has strengths… which hopefully includes being smart enough to know when to consult with professionals. For example, we hire structural engineers and architects to give us the security that buildings won’t succumb to gravity, or bad taste. Code officials ensure we have met life safety.

But who watches our back when it comes to energy efficiency or durability? What is the risk of not covering this area? About 80% of the sustainable design decisions that affect a building’s energy performance are made at the early design phase. Who is the “expert” giving wise advice? While there is an army of LEED accredited professionals who are available, the availability of qualified energy experts is a bit trickier. This has generally not been an approved line-item in the budget.

Energy modeling software may help fill the gap. In our previous blog, we discussed BIM tools for increasing constructability. 3D modeling can also support a more rigorous design analysis, for example, to determine installation details which will be most durable and withstand air and water damage. The integrated Green Building Studio software can also be used to identify the best design for lowest energy consumption.

The question again, who will use this energy modeling software? Is this the architect, who generally is specifying the building envelope, but doesn’t normally work with optimized HVAC systems? Or the MEP, who designs the HVAC, but is typically not involved in specifying the thermal envelope. And what about dew point analysis? Who makes sure the building doesn’t rot? Is it time for a new professional category to evolve, much like we now rely on structural engineers? Green job: energy engineer. Will work closely with architect, structural, and MEP engineers to identify the most energy efficient design and HVAC options.

Residential is equally complex. For my recent LEED Platinum home, we hired an energy modeler (a rare find), an HVAC contractor, and an Energy Star rater. Each of them had separate software, none of which was interoperable. And then there is the disconnect between the BTU load determined by the energy modeling software and figuring out which is the best HVAC system for that application. Is it forced air, radiant, geothermal, solar? While ACCA does have a Manual -S software to help with this decision, who is going to use it? Energy modeler (nope – not interested in the liability), HVAC contractor ( nope – is already pushing the system they are selling) or the Energy Star Rater (nope – not their job). Green job opening: energy modeler.

Energy Modeler: Achilles Heel … or Green Job?