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Archive for November, 2010

“Think like a raindrop.”

That’s advice for design professionals from Washington State-based building envelope consultant Ray Wetherholt, PE, RRC, RWC, of Wetherholt and Associates, Kirkland and Olympia. Since founding his business in 1984, Ray has made a specialty of helping to create building envelopes that resist water intrusion, and fixing those that don’t.

Ray Wetherholt, Wetherholt and Associates

Water is good at getting into walls, he says. When it does, depending on the way the building envelope is constructed , nasty problems can result.

Mold, and the litigation it brings is one of the most widely known problems. Water also can warp, decay and rust building envelope components; delaminate paint; and deposit ugly stains on interior and exterior walls.

But if you look at water intrusion from water’s point of view, Ray says, it will help you navigate a building envelope landscape that is constantly changing and evolving.

Though mold caused by water intrusion into walls gets the press, uncontrolled water can do other bad things, like depositing nasty metallic stains on concrete stucco, as shown here.

Since water follows gravity, use water-shedding designs that let water do what it wants to do – flow downhill. Don’t depend on laps that buck water or interrupt the water flow. Don’t build flat shelves, or try to catch water flowing down a wall.

“It’s really pretty simple,” Ray says, “but gets mucked up a lot for the sake of ‘the design’.”

Since water can find its way into walls as liquid, or by hitching a ride on air currents as water vapor, and then condensing when it hits a dew-point, structural walls must be air- and water-tight as possible.

And since total air- and water-tightness is not possible, building envelopes need to be able to dry out when a little water does get in.

“Designs are imperfect,” Ray says, “as is construction. So the goal isn’t a ‘perfect wall,’ but a wall that works.”

It’s when they don’t work that Ray and his fellow building design consultants get most of their business.

Water in the walls delaminates the paint in this window opening as it evaporates out.

“As a friend of mine puts it, ‘no one invites us to the wedding,’ Ray says with a chuckle, ‘just the wake.’”

Failure to integrate wall components is one of the biggest reasons water gets into walls, Ray says. A common example is leaving out transition flashing. That error lets water penetrate at transitions points between components, such as where a deck edge or railing meets a building wall.

Architects aren’t always focused on how to tie it all together, and contractors don’t have details. “That’s what keeps guys like me employed,” Ray said.

Lack of redundancy also contributes to water in walls, he said. Relying solely on sealant or caulking, for example, will be a problem when the caulking fails in a spot or two.

On the other hand, there are systems that work, sometimes just by luck. A building can have multiple places water from outside can enter, but if it has a positive pressure, the water doesn’t go in easily.

This photo shows poor window/flashing/cladding/roofing integration. Here, the canopy roof is not integrated with the brick wall, and the roofing is not flashed into the window in a manner that allows for future roofing. Water build up on the roof will go under the window. Fortunately the location is sheltered, so hasn’t leaked in the two years since construction.

“I remember one time a crane collapsed and sheared the exterior walls off about six stories on the North elevation of a nine-story building,” Ray said. “For awhile, the building basically had a tarp for a wall on that side. Yet, positive pressurization and facing away from the prevailing wind helped keep water from coming in.”

Whether or not you get water intrusion may depend on something as simple as which direction your weather comes from, Ray said.

In general, though, most buildings get water in the walls sooner or later, since no materials last forever. Good designs take that into account.

“I think we’re seeing more problems with new construction as buildings ‘tighten up,’ and trap moisture in the walls with impermeable vapor barriers,” Ray said. “That’s why vapor-permeable air- and water-resistive barriers are becoming such a big deal.

This photo shows severe water damage at a rough opening flashed with a non-vapor-permeable peel and stick membrane. If vapor-permeable materials had been used, the wood could have dried out and the damage wouldn’t have occurred.

“And we’re building faster now, with less investment. We’re not building with durability as the end result, but budget.”

Even in that environment it’s still possible to design and construct building envelopes that work by design and not chance, Ray said.

For that to happen, everyone – design professionals to trades people – must understand that the various parts of the building envelope have to be integrated to work together to resist, shed and expel water.

The tools to do that exist, from advanced flashing systems to the latest vapor-permeable, fluid-applied air- and waterproof barrier systems.

To take full advantage of these resources, however, it helps to think like a raindrop, Ray said.

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Dwayne Fuhlhage, PROSOCO’s director of regulatory affairs, is attending GreenBuild. He offers this report from day 2.

GreenBuild Conference: Day 2
by Dwayne Fuhlhage, CHMM; Regulatory Affairs Director

I just completed Day 2 of the GreenBuild conference. My education sessions for the day were focused on green building codes and indoor environmental quality (IEQ).

But first, yesterday I promised photographic proof of the strumming USEPA program manager.

A U.S. EPA program manager provides a musical interlude at GreenBuild, Wednesday. photo by Dwayne Fuhlhage

I think it fair to say that the green building movement is populated by a group of very intelligent and iconoclastic people. And that’s actually the best part of being here for me. Over the last couple of days I met up with people I work with in ASTM and NSF consensus standards.

We had great conversations on how green products and concepts have come along in the last few years and where we think things are headed in the next few years.

Gazing in the crystal ball is a tough exercise. The whole purpose of LEED standards was to create market transformation. In 10 short years, we stand on the edge of the first statewide green building code, CALGreen, and the approach of the first national green building code, the IGCC. The market has indeed transformed.

PROSOCO President David Boyer asked me for a takeaway from the education sessions I’ve attended thus far. Here it is: the definition of green and sustainable construction is being written and rewritten every day by what essentially counts as an insurgency.

Here are a few stories that drive that home for me:

This morning I learned about the new New York City green building codes – total shock on this one. I wouldn’t normally think of NYC as being an insurgent organization, but they took a long look at LEED and the developing ASHRAE 189 standard and decided neither was a good fit. So they did their own stakeholder process and created their own standard. Will they adopt the IGCC in 2012? Sure doesn’t sound like it.

During lunch today with the co-founder of Berkeley Analytical Associates, I learned that the IEQ standard our Consolideck products are tested to was the brainchild of four primary authors that pushed it through. Berkeley Analytical, with all of 12 employees, was a major part of that.

At the Master Speaker’s panel, one of the guys behind the original Dyson bagless vacuum cleaner referred to it as “disruptive technology.”

They rolled the product out to great skepticism – everyone used vacuum cleaners with bags – why would anyone want to make the switch to this strange, unproven technology? The punch line: within 18 months it was the best-selling vacuum cleaner in America. He fully expects the evolution of green products to move along in fits of disruptive technology.

The speakers yesterday promoting energy use labeling for houses – insurgents all. From their perspective, a focus on using cheap off-peak energy just because it is there isn’t good for the environment. Their ultimate goal is to use labeling as a means to let consumers decide how much actual energy they want to use and whether that is a deciding factor in buying a home.

By all accounts, PROSOCO is a participant in the insurgency. Several years ago, we rewrote the specifications for silicate densifiers. Smart consumers picked our lithium silicates because they didn’t require as much work or generate a lot of rinse water. I was pleased to learn that the Consolideck side of our booth was getting a lot of traffic.

Polished concrete was big news in the green product trade journals two years ago and then they moved on. I walked by competitor’s booths that were totally devoid of traffic. Our brand and our message are sticking in an ever shifting market place.

We’ve been working to rewrite the rules on air barriers for several years. It’s crazy that energy modeling doesn’t count air infiltration reductions in the overall building equation. You know what, there’re plenty of forward thinkers in the green building movement who see the sense behind the technology and are moving on regardless of what the models say. They want real energy-use reductions.

Our alignment with BEI is all about moving the bar up yet again. The small-scale chamber in our booth drew lots of attention. When visitors found out we’re collectively set up to test entire wall assemblies they got downright excited. Yes, the highest performance products cost more money and you can’t see them behind the siding material.

In LEED V3, there’s no credit for upping the ante on envelope design. But designers and builders know all about the cost of envelope failure – rotten wood, mold and all.

My last thought for the day comes courtesy of the Chief Building Inspector for San Francisco during the session on CALGreen. He pointed out that he is not part of the design team. When he picks on architects, it’s because he considers his customer to be the building owner 30, 40 or 50 years from now.

He already is seeing failures of green products in buildings put up in the last ten years. He’s seen buildings go through three sets of windows in the span of his 30-year career.

The message to me is that the marketplace is ready for the next steps in high-performance product evolution. I’d say building walls that can weather hurricane-force wind and rain is a good start. Being part of the insurgency is a lot of work, but it’s also a lot of fun.

And what conference blog would be complete without a parting shot:

Author Dwayne Fuhlhage and new friend at GreenBuild.

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Dwayne Fuhlhage, PROSOCO’s director of regulatory affairs, is attending GreenBuild. He offers this report from day 1.

GreenBuild Conference: Day 1
by Dwayne Fuhlhage, CHMM; Regulatory Affairs Director

Retired Army general and former U.S. Secretary of State Colin Powell talks leadership at GreenBuild 2010. photo by Dwayne Fuhlhage

After working PROSOCO’s booth for the last two years at GreenBuild, I am here in Chicago as an attendee. I learned a lot in the conference sessions today and I’ll try to share more before everything winds down Friday afternoon.

The overall vibe is optimistic. There’s a lot going on in the sustainable codes and standards arena and I get a real sense of momentum from the conference session presenters and attendees. Of course, change is only good for companies and individuals that are keeping up on green building technologies and trends. I’m feeling confident about PROSOCO’s efforts. While waiting in line for an Indoor Environmental Quality (IEQ) session, the architect next to me asked “So what makes your products green?” That’s a question I can answer confidently and without hesitation – I take that as a good sign.

Best stuff from today
The opening Plenary Session featured Retired General Colin Powell talking about his work with green distributed power generating systems and leadership in general. Colin Powell on leadership – cool.

Energy Labeling: A Market Catalyst – This session featured speakers who have been working on innovative energy use calculation modeling and building labeling in the Pacific Northwest. The big idea is that consumers and sellers will be well-served by showing the energy use profile as a simple label much like the fuel economy estimates for cars. One of the presenters does design/build for energy efficient houses including a variety of Passive House projects. There was a good sampling of pushback in the audience, but also a lot of excitement about a labeling approach that they are turning into a regional reality.

Designing for Indoor Air Quality; A Commercial and a Residential Perspective – First off, this session was absolutely full; no getting in without pre-registration. I’ve been doing a lot of standards work on IEQ issues and this reinforced what a hot topic IEQ is in the sustainable building sector. I expected this session to be dry and was surprised by the guitar strumming/singing USEPA program manager. Yes, I have photographic evidence.

I also expected a stock discussion on product VOCs and toxics. While he mentioned these issues in passing, he put much greater emphasis on IEQ issues caused by poor sealant and waterproofing details and installation. He also showed the correlation between air infiltration and IEQ problems caused by the moisture transported into the building due to having a flawed building envelope. I also learned about the benefits of infrared cameras as a diagnostic tool for IEQ issues. Sounds strange, but it goes like this:

IR shows temperature differentials caused by damp insulation and building materials. Damp materials equals mold. Mold equals IEQ problems for building occupants.

I’m not sure if our friends at BEI (Building Envelope Innovations) use IR cameras for their building forensics work, but I’ll share this information with them.

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Stachybotrus Chartarum, a toxic mold and basis for lawsuits, has colonized this structural wall as a result of uncontrolled water penetration and movement.

A library in Itasca, Ill., had leaky windows.

The library was only about 10 years old. It was an award-winner too – for design. It was clad with DAFS – Direct Applied Finish System. As you probably know, this system is similar to EIFS – Exterior Insulated Finish System, except it doesn’t have the insulation.

What it did have was mold.

That was revealed during the investigation by Building Envelope Consultants Ltd., Arlington, Ill. The investigator, firm principal Kami Farahmandpour, said the city was lucky. The mold hadn’t penetrated to the library interior.

Nevertheless, the cladding had to come off so the contaminated wall components could be replaced.

Building Envelope Consultants prescribed a new air- and water-resistive barrier, a redesigned drainage system, new leak-proof windows, and recladding in conventional 3/4-inch stucco.

In the end, the library’s exterior appearance didn’t change much, but beneath the stucco skin the components were altered significantly, giving the wall a much better chance against buildings’ worst enemy – uncontrolled water movement.

About 90 percent of Kami’s business comes from building owners with problems like the Itasca library. The rest comes from design professionals seeking to avoid those problems to begin with.

Kami Farahmandpour

Kami, an engineer by training, and forensic building detective by experience and predilection, wishes it was the other way around – 90 percent avoiding problems to begin with.

The issue, he says, is the incredible and increasing complexity of contemporary wall systems. Long gone are the days of simple, thick masonry walls.

We ask walls to do a lot more today, Kami says. We demand all the durability, performance and aesthetic appeal of solid masonry walls, but we want it cheap, light and code-compliant.

Handed those requirements, the industry has come up with hundreds of products that can be used in thousands of combinations. Results range from walls that prevent costly, destructive air and water leakage in conditions up to and exceeding Category 5 hurricanes; to walls that leak air and water; trap moisture; grow mold and deteriorate in alarmingly short periods of time in even the most benign climates.

This wall section drawing shows the increasing complexity of building envelopes as we ask them to do more and more for less and less. Unfortunately, the more complex the system, usually the greater the potential for errors.

Getting the right results means navigating a sea of curtain walls, panel walls, precast, thin brick, CMU, air barrier systems, vapor retarders, flashing systems and much more.

Some places, like hurricane-prone Florida require impact-resistant walls and windows.

Some clients, like the federal government, require blast-resistance in their building envelopes.

It’s no more reasonable, Kami says, to ask an architect to be familiar with every combination and location of every system in every kind of wall assembly than it is to ask a general practitioner M.D. to be familiar with every medical aspect of the skin.

There are, after all, general practitioners and dermatologists.

Throw into the mix the fact that new products and procedures for building envelopes – let alone other components of buildings like security systems, flooring or HVAC — emerge at a dizzying rate.

Add in that each new product needs careful, usually time-consuming research and evaluation before consideration, and the reason for the emergence of the building envelope consultant starts to come clear.

Kami says he understands the reasons design professionals have been reluctant to take advantage of the resource offered by the new specialty.

Professional pride may be part of it, he says. Also, design professionals can be hesitant to divvy limited budgets even further, especially when they’re using wall systems with which they’ve had success in the past.

On the other hand, clients, insurance companies and lending agencies sometimes require the participation of a building envelope consultant as assurance things won’t go south from water leakage after project completion.

All have been bitten by it, Kami said. Water leakage is one of the most litigious areas of construction.

Design Verification Testing - In this fluorescein dye test, using a Design Verification Test Chamber, the window assembly failed to stop water penetration under Category 1 hurricane conditions (winds 74-93 mph, barometric pressure of >28.94 inches). Such testing helps consultants and design pros spot and correct weaknesses in wall assemblies before construction begins. Correcting it after construction is a lot more trouble.

A few simple questions can give you an indication as to whether or not you could benefit from talking to a building envelope consultant.

Building owners – Does your building have a water leak, or premature deterioration of wall or roof elements, but you can’t pinpoint the cause? Do repairs not seem to fix the problem?

Design professionals – How aware are you of the different purposes and uses of vapor-permeable and non-vapor permeable air barriers, and where each should be located in the various kinds of wall assemblies? How “up” are you on the latest products and procedures from the major manufacturers of building envelope components? How familiar are you with integration of different types of cladding – masonry and EIFS, for instance — in the same wall assembly?

If you’re vague on these questions, Kami says, you may want to get in touch with people who spend all their time studying and working on these specific issues.

Sealant, Waterproofing and Restoration (SWR) Institute and RCI Inc., are both good places to find reputable consultants, Kami says. RCI Inc., is an international association of consultants, architects and engineers specializing in roofing, waterproofing and exterior wall systems.

SWR Institute membership comprises more than 230 leading commercial contractors, manufacturers and consultants.

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