Constructability

Now that we’ve determined the survive-ability of a structure, it might be useful to look at its ability to be constructed. The trademark contractor “can-do” personality can usually translate most anything drawn on paper into reality, but this might involve unnecessary costs in both product and process. Why not ask for constructability input in the design phase – and avoid excess costs?

And therein lies the crux of the issue. At what time in the process and what level of detail? Waiting for the plans to be drawn for a checklist review is a no-win situation. The contractor is put in a position of fixing flaws and wounding egos. On the other hand, too much detailed information too early in the process invites confusion in design, or is just plain forgotten. The disappointed contractor is unlikely to be willing to volunteer any suggestions in the future.

The Construction Industry Institute (CII) has developed a constructability guide, which is based on the presumption that constructability input needs to be an ongoing process throughout the entire project. Using Building Information Modeling (BIM) can help make this a more efficient process, since any updates flow throughout all the models. And, because the architectural, structural and MEP models are linked, any one perspective can be the driving force for design. For example, in a high seismic area, the structural component might be engineered first, preferably with input from the contractor to ensure constructability. The architectural model could then be designed around the structure. Inside –out.

A written constructability guide can be helpful in identifying the right level of detail at the right phase of construction. It can also organize lessons learned from previous projects. Clash detection software in BIM can also catch many of the problems while still on paper (or in the computer), but there is no substitute for bringing people together for a project review. About 83% of constructability knowledge is not written down in any form, but comes from the technical skills, intuitions, and insights which is in the heads of experts. Just provide them with a few examples of what you are looking for, and then sit back and listen.

Listen, Respect and Learn.

Passive Survivability

When oil platforms blow up, volcanic ash is blown across a continent, or when earthquakes tremors shake a bit too close to home, my thoughts turn to passive survivability. This term is generally used to describe a building's ability to maintain critical life-support conditions in the event of extended loss of power, heating fuel, or water. I.e., how long could you live off the grid?

Passive survivability adds a self-preservation motive to the existing strong economic incentive of energy efficient construction. But is also calls for measures such as istern water storage, electric vehicle battery back-up to solar panels, and alternate sources of heating, like a wood stove. Not surprisingly, this harkens back to vernacular design, which was more disaster tolerant by matter of definition. We relearn to use windows for daylighting, harnessing the sun’s warmth and the wind’s coolth.

A key component of this survivability is the ability of the structure to survive when set upon by the wrath of man or nature: fires, wind events, driving rains and freezing temperatures. We typically think of vulnerability to Hurricane Katrina & her many cousins, but it is the army of mold and mildew following such events which really destroy a structure. In warm weather disasters, the penetration of the outside shell is followed by an intrusion of moisture which can quickly render the building uninhabitable. In the wintry north, this may occur when heated indoor air escapes up to the snow-covered roof and catalyzes a series of thaw, freeze, backup under roof shingles, drip into the house, rot, mold. Same story, just the cold weather version.

What to do? "High insulation and high mass with some passive solar gain and summer shading will dramatically improve survivability,” says John Straub, Ph.D., an engineer and building science expert at the University of Waterloo in Ontario. The mass prevents penetrations from air-born missiles in high wind events in the worst of times, and provides temperature moderation at all other times. The best part about mass (concrete, brick) is that if it gets wet, it will dry out and NOT mold. If the insulation is equally not moisture sensitive (ie EPS, or NEOPOR), and is continuous from wall to ceiling, then at least one is assured that the building envelope will continue to function as designed, both structurally and thermally.

You can sleep on that.

Aging Gracefully

French women, wine and buildings. They all age gracefully. They start with good bones, lovingly tend to their needs over the years, and adapt to reality. This is not Disney.

By contrast, some cultures build instant slums. Poorly designed, cheaply built so they start falling apart almost immediately, and catalyse a slum mentality of disregard among its inhabitants.

How I wish I had a mental imagery camera and could capture what examples this has evoked. For these are relative terms. What is damaged, or what is distressed? It is old, or antique? Outdated, or mid-century?

Let’s start with the good bones. A person is born, but “We shape our buildings, and afterwards our buildings shape us.” (Churchhill). True. The first consideration is intention of the space for gatherings of humans and their activities. Architects talk about “programming” this space, which is often distilled down to a single word, i.e.: office. But given the opportunity, people will take over and start re-shaping the buildings to fit their needs. It starts with furniture, then walls get torn down, or built up to create the space size needed. Outdoor space gets add, enclosed, and then added again. A building with good bones has an intact, independent structure to allow for these flexible components. It has a style and distinctive features which can be replicated, complemented, embraced.

Aging gracefully also calls for good building science in the design. Let the rains come, let the snow drifts pile up - if the building is designed for the element, to shed rain, to protect from cold, to shield from sun, and the materials are chosen for durability and maintenance. Wood for example, is a beautiful material which can be maintained through regular staining and sealing. It ages gracefully as it gets dings and bumps. Painting the wood looks shiny new, for a short while. Then it triggers a point in the maintenance where the paint has chipped, had too many layers and drips, and needs to be sanded, to get back to shiny new. A bit like plastic surgery.

So let us start building for the next generations. Simple or elegant, built to last, built to live.

Further Reading
Stewart Brand, How Buildings Learn (Penguin Books,1994)

Green Engineering

The EPA is ahead of me on this one. Imagine that 65 engineers and scientists convened a conference in 2003 with the goal of defining the principles of green engineering. They looked at processes and products which would protect human health and least impact the environment. I was most impressed by their expressions of concepts like holistic, systems analysis, and integrated environmental impact assessment tools. I was intrigued by the engineering of the processes…

I was still thinking of this as I read an article about green engineering, which went into more detail about the selection process of structural building materials based on embodied energy. The focus was on the selection of the material, the calculation of its’ environmental impact. The materials to support what someone else had designed. I wondered, is construction the only industry left which has not tapped into the engineering skills to identify solutions at the design phase?

Think of the potential impact. For example, the engineer on the LEED Platinum Banner Bank building was challenged to find the most efficient structural system which would offer the most benefits, green or other. The solution was to relocate the exterior bearing walls in from the edge by about 15 ft, and cantilevering the slab floor out to the new exterior curtain walls. The total lineal footage of the concrete bearing wall was reduced, interior supports were eliminated, and a thinner slab took up less room, resulting in one extra floor within the given height of building. Fewer materials, less embodied energy. This was an engineering solution which optimized design and materials.

The construction process in the U.S. doesn’t facilitate the involvement of engineers in design. So-called value engineering is, in fact, a request to do more with less, but the word value is a misnomer. The owner “values,” or the design values are not in consideration at that point. My engineering colleague confirms that engineers are taught to design to constraints, and the software is meant to analyze given materials, but is not equipped to help determine the selection of materials.

So, engineers out there in Blogsville, can we get more Banner Bank solutions? What parameters would need to first be defined in the conceptual design stage to inform your selection process of “process and product.” Can we engineer solutions?

Behind the Scenes Green

I’m in the final stages of a LEED-H Platinum project, which also took on the challenge of universal design, adaptive re-use, historical rehabilitation and 100 yr durability on the exterior envelope. Oh – and a NETZero HVAC system (PV output = Heat pump demand), and xeriscape landscaping. We also wrapped the entire house in 4” of a high R-value NEOPOR foam, and introduced Serious fiberglass windows with a U-value of .15 (i.e., WAY better than Energy Star). I was proudly describing all this to a realtor, whose only comment was: “Yes, but you’ll need some green features if you want to attract buyers.”

O.K. – So I exaggerate a bit – but their point was that I needed to have some identifiably green materials for homeowners to see and to show off. Things they understand, like bamboo flooring, and concrete countertops. Yet the entire “embodied energy” of all the building material of a residential structure typically accounts for only about 10% of the total Life Cycle Assessment (LCA), or environmental footprint of the building. What accounts for the 90%? Operating energy. Saving energy is by far the “greenest” thing a builder or homeowner can do.

According to Dr. Steven Chu, US Secretary of Energy, energy efficiency is one of the lowest cost options for reducing US carbon emissions. It can save both energy and money. Don’t get me wrong, I do endorse the “do no harm,” and cradle to cradle concept for materials, but I am just as interested in the durability of that material. Because if the house is built to be energy efficient AND durable (maybe even outlasting its mortgage!) then these energy savings can compound into the future.

The DOE is taking on the challenge of developing a strong retrofit industry and recently announced an innovative effort called "Retrofit Ramp-Up," which will tackle whole neighborhoods at a time. Their support roll-out includes field-application energy savings software for home inspectors, training for weatherization and instrument support for infrared inspections to improve the quality of work. For those of us who have waited for the resurrection of this “enlightened” approach since its political demise in the 70’s - THANK YOU, Dr. Chu.

Further references:
NEOPOR used in ICFS

Creating a Stress-Free Environment

Image a “green” building environment  - healthy, lots of daylight, clean indoor air, comfortable, natural.  All designed to reduce stress, improve productivity, and keep people happy.     Now imagine the process of constructing this environment - redline documents, RFIs, field repairs, injuries and a lot of lawyers.   Bad karma.  Is there a way the process could learn from the product?

Brent Darnell believes so.  He teaches stress management, time management, and life balance for the “tough guys” in construction.  Just yesterday he taught a classroom full of construction students a few tools for meditation.  Yeah.  Maybe this can help them stave off the burn out and stress-related illness which is prolific in the industry.   Good diet and some exercise would help.  Check out the Tradesmens yoga.

We don’t think about people in the construction process.  We like nuts and bolts.  But people are the key in the process to get the right nuts and the right bolts in the right place at the right time -  the first time – NOT after a change order.    A Dale Carnegie study revealed that 85% of an engineering company’s financial success is due to “human engineering” – personality and the ability to lead people.  But these skills are woefully underrepresented in our curricula, in our resumes and in HR hiring processes.  

Interpersonal skills, empathy and social responsibility are three of the emotional intelligence skills which are least represented in the construction industry, according to Darnell.  Yet these are the very skills needed for teamwork, for interactive design, for lean construction, for all those great concepts we have a smooth running construction process.   And this is an upward spiral.  Lower stress helps teamwork, improves the information flow, reduces delivery problems, and reduces stress.. even more.   It does sound appealing.

So next time you are managing by crisis, breathe deeply,  hit pause,  and create a little stress-free environment for yourself.  It will “detox” the crisis, and bring it to a level where you can work with it.

Reading:

Previous blog -  Hybrid Solutions – (I’ve been in zen mode lately…)

The Emotionally Intelligent Workplace, Daniel Goleman and Cary Cherniss, 2001

Hybrid Solutions

Tapping into the spaces between the thoughts. It is the zone you seek in rapidfire brainstorming exercises. Chanting mantras can get you there as well. For me, it comes in the mindless moments when I am out for a run.

Divide and conquer was the tenet of the great American mass production industry; which worked fine as long as there was one product for all. Toyota dipped back into the original doctrines of Henry Ford and discovered that efficiency could better be achieved by rethinking the product in terms of value, and then organizing to allowing for flexibility in product, worker training and manufacturing setup. Of course, there has since been a deviation from that path – with consequences.

The word “hybrid” comes to mind as a result of breaking old patterns and mixing things up. Like linking gas and electrical sources in a Prius, or the FLP Group Utility’s experiment in using the sun’s power as an adjunct to coal or gas in producing electricity. Pulling the best technology from tank and on-demand water heaters produced the 98%+ efficient Eternal Heat. Hybrid is nature’s way of evolving - lovable mutts, stronger plants, resistant flu viruses…

Hybrid construction also calls for a change from old patterns. The Lean Construction process works by pulling together professionals and trades right from the design stage, to work through clash detection, identify optimal solutions for an integrated delivery, and eliminate any waste which doesn’t contribute to long term value. Product solutions happen through a cross-over of CSI categories, but process solutions require hybrid thinking.

Next time you get stuck on a problem, try this little experiment. Take any piece of paper with writing on it and turn it with the writing upside down. Now find a letter which has a little enclosed space, such as “a,” and stare into that space as if this were to portal to Starship Enterprise. That’s it. Your mind will want to stray back to “busy”ness, but keep heading out to outerspace. You’ll know when it’s enough. Don’t expect any earthshattering epiphanies the first time, but sufficient practice will help you tap into this space between your thoughts – and your own hybrid solutions.

Let me know how well it works. The world needs you.

Capillary Break

The rain this year seems endless. A constant barrage on the building envelope, in the form of pounding rain, waterlogged soil, or evaporating moisture when (and if) the sun finally comes out. And then my thoughts turn to capillary breaks…

Is this the first step to a heart attack? No? Then why does there seem to be so much resistance to adopting this concept? Really, it is simple. The ground can hold moisture. Most building materials used in exterior walls can wick moisture. Buildings shouldn’t have moisture in their exterior walls – especially when the material is susceptible to things like rot or mold. So what do you do? Wood framing practices is to break the pattern of wicking with a non-permeable material - like a sill seal foam gasket. New concept? Not really. Look at these photos – one from Switzerland and the other from the mountains of North Carolina. My guess is they didn’t trade e-mails over 100 years ago to compare notes – but both figured out a solution against rising damp.

And what if the building material does NOT rot – like stone or concrete? The water still wicks up, and then it moves from wet to dry. This moisture could then collect on the paper backside of sheetrock, or into some wood work, or evaporate into the air (indoor or outdoor). And, like a science experiment – this wall will continue to wick up water and evaporate it into the driest medium. We may not hear as much about these problems, because the concrete itself won’t rot, and there may be a few cases where the path of the moisture won’t cause damage. But the problems may surface elsewhere and get blamed on the HVAC: excess moisture leading to carpet mold, swollen wood trim, wallpaper peeling.

What is the solution? Slab foundations should be disconnected from ground water in any case. For footings, slather on a waterproof coating before your place the stemwall/ basement wall. Anything with an acrylic component, or a rubberized membrane.

Prevent liability which may lead to heart-attacks – go for the capillary break.

Further reading:
Petit, Betsy. RR# 0509b Details for Avoidance of Mold—Foundations. www.buildingscience.com

Solar Panels for All?

Photovoltaic (PV) Panels are the political darling of the green movement. Tax incentives and rebates are nonpartisan, numbers can be tallied to demonstrate great energy savings, and PVs generate jobs for Americans. Yeah! All true. Yet there is another story to be told.

Having just completed the final paperwork on my own PV array, I am amazed by the complexity. There were 4 agencies, each with their own required certificates and documentation, cross-linked, co-dependent, and often “pending.” Add to this burden the multiple visits and additional requirements set up by city electrical inspectors who are still trying to figure things out. Dozens of e-mails, phone calls, papers. Who has the time?

But the greater question is, who has the money? While it is true that the final cost of panels can be reduced greatly by rebates and tax incentives (www.dsireusa.org for a listing in your area), these presume that you can front the funding. Utility rebates are probably the most helpful, as the money comes as a check within a month or two after submittal. Tax incentives are great, if you can wait until tax time – possibly a year after your panels are in. And, you need to have earned enough money, and accrued enough taxes, to cover the tax incentives. If not, you can carry it over, and wait another year.

Back to our discussion of eco-equity. In truth, even with the incentives, PV panels still take many years to pay for themselves. But eventually they do, and they provide an insurance against future high electrical costs. Utilities and governments see PVs as part of an overall solution. But the people who are cash poor and could use help reducing their electric bills can’t afford the upfront costs of PVs.

Options? Could the PV installer companies process the paperwork for a customer? Which utility companies offer a third party financing? Could the local governments provide coordination between all the parties, including the building inspectors? Or how about this - could the PV panel solution be linked to a whole house weatherization program, so the demand for power is reduced (especially in hot climates, ie high AC bills). Or, for a really smart approach, support the initiative for the mortgage industry to incentivize energy efficient improvements (http://www.architecture2030.org).

Combined, these measures might increase the total quantity of PV panels installed. In turn, this stronger market can attract PV manufacturers to set up operations in the US. And, an increased and steady demand can help bring prices down - for all.

Would love to hear of good market examples…