The Pains of Progress

After a recent conference, a seat-filler proclaimed – “The presentation was good enough. But, I think some of these ideas are suspect. Maybe 20% is accurate, but I bet other industry professionals would say he doesn’t know what he is talking about.”

Slowly We Go…

The subject matter related to how to quantify home performance and help homeowners live in and keep a healthy home. This is the realty of our industry. There is an HVAC-ton of apprehension and willful refusal to change understandings and habits (see what I did there with that HVAC ton…I’m a quick one, I am…). Larger, more youthful areas of our country likely have an easier go at this. Rural, more aged and conservative communities likely are slower in acceptance.

Building science is not rocket science…common knowledge among building scientists

Building science is not high-level physics. It can be, but most of what practitioners need is not high-level. All building science really does is incorporate the “why” into the “how.” The other thing building science does is provide on-going advancements in testing to confirm – confirm performance, confirm deficiency, and even resolve deficiency. And everyone appreciates resolution, right?

Err, maybe not so much. Turns out, without active and prolific enforcement, many regions of our country remain happily humming along executing at the “same old, same old” quality of construction and home performance. Don’t believe me? Listen to any number of trades-related podcasts – the subject will and does come up routinely. We know what we know and we do what we know and we won’t do what we don’t know unless and until someone else makes us know it (eat my biscuits, Dr. Seuss!).

Hitting Home

In the south, TVA remains king which affects attention to energy consumption

For my business in the conservative South, where TVA still reigns king and electricity remains less expensive per kwh than many other regions of the country, getting anyone to see me as anything other than crazy is not easy. The thing is, there’s no motivation for anyone local to see the merit in using my services – if consumers don’t ask for it, and codes departments don’t require any of it, then what compels any one builder or contractor to learn and do better? Literally, there is no competitive edge in doing so in our market. Yet.

See, that’s my hope. There are a few builders in our region who are doing “some” portion of a pretty good house detail, but no one builder has started to build exclusively with the total details package. I’m hopeful that the trend will continue. Hell, I’m even starting to kick around the idea of doing it. Licensing isn’t that large of a hurdle. If I can understand the building science of a home, and how to test for performance, then surely I can manage a license exam. Based on what I have been seeing for the last decade, I shouldn’t have an issue. Boy, I’d be embarrassed if I did.

New Year Feel-Goods

Going into the new year, I’m hopeful I can begin to find a way to better access the existing housing market and help owners and builders begin to make choices that benefit everyone. As a builder, if you work to change some practices – be it materials used or methods of construction – then you could see improvement in your profit, in your product, and in your client interest. As a homeowner, if you demand better conditions from your home – more than the aesthetics of the kitchen or baths – you could see less money spent on utilities, healthier indoor air quality, and a greater longevity of the home itself. There are many reasons why understanding how your home is failing could help you take control. Such control yields more value for the money and time spent on and in your home.

May the end of year bring you blessings and peace

TNergy Services wishes all of you a safe and enjoyable holiday season. Whether you travel, stay in place, hang out with copious amount of people, or cuddle up with a few good books – may stress not be a mitigating factor for choices made. And, in the new year, if you are ready for a new adventure and to take control of your home, give me a call. I’d be honored and humbled to be of help.

No Flashing Where It Counts

Case Study – Flashing at Dissimilar Materials Joints

In roof framing, it is widely understood that those areas of most interruption, or planar differences, pose the greatest risk for leaking (think valley, or greedy dormer). Ergo, the more complicated a home’s roof line, the greater risk for leaking. How do professionals (not you, Grandpa – real, actual professionals industry trained with real world experience) manage this? Flashing.

Now, let’s move that concept down from the roof to the wall assembly. If you have a wall made of wood, that wooden wall will inevitably end. In our middle Tennessee region, it usually ends on the foundation (concrete blocks aka CMUs), but slabs are becoming more prevalent and we do have old housing stock (stone and brick foundations).

Where that wooden wall ends (you have to picture the wall naked – of siding/cladding here) the materials are dissimilar (usually wood and concrete or masonry). Dissimilarity, in home performance, is the ideal location for issues to develop – usually via air, moisture, and pest. The solution would be, like roofing, flashing. The problem is flashing of wall assemblies and components is not a highly regulated area of home production in our region and, based on what I see often, there is a wide spectrum of understanding and skill by those performing the work.

Where a wall meets a foundation, or any transition, merits your attention — where is it here?!?

Often times, wall flashing is overlooked, or under executed. In some of our housing stock, the home survives with deficient wall flashing purely because the interior enclosure is so very much perforated (read, not air-tight) and the walls can dry. But what happens in our younger homes? Let’s see.

The Home

This home was built in the mid-2000s and likely was intended to be a moderate-to-high-end home based on materials used and aesthetic finishes. Composite cement fiber product was used for siding. Concrete cast stone veneer (lick and stick as it is so lovingly referred to here) was used for both foundation veneer AND some areas of siding. Where the cement boarding terminated and adjoined the stone veneer, there sat a shelf. A very flat, flat, shelf (see photo above).

As best I could tell, there was no flashing beyond a typical weather resistive barrier installed along this common joint line (which ran around the entire perimeter). And, this is for yet another article, the concrete cast stone veneer appeared to be adhered via thin-set directly to the wall assembly over the WRB with no adequate separation and this negates any water management ability…but, I digress.

Our flat joint had no special flashing installed. Flat surfaces hold water, or at least don’t let it drain away and off. When water is held flat, it will follow capillarity (think trees) and find other points by which to travel – up, down, sideways. At our dissimilar joint with no special flashing, the water readily accessed a percentage of the walling assembly over time. Time and moisture vs. OSB. Which do you think wins? Hint: pick moisture.

This is NOT how the rim joist should be looking — if only there had been flashing…

This home that was less than 20 years old, was set up for disaster from the onset of construction. With no attention to flashing detail, and no apparent understanding of needing to protect engineered laminated products (OSB, manufactured I-joists which were the substructure framing), this home started rotting very soon after construction. And unlike old housing stock that was more drafty, this home was less drafty (still drafty, just less drafty). Less drafty means less drying or longer drying time. Prolonged exposure to the moisture delaminated the resins/adhesives in the engineered materials, primed the wooden fibers for pest snacking, and degraded the general strength of the framing.

ENTER ME

By the time I came on the scene, the murder had already occurred. The un-flashed joint work at the exterior was my first clue. My knowledge of the abhorrent installation practices of concrete cast stone veneer in my Tennessee market was my second clue. A very pervasive and present musty odor in the garage was my third clue (have we talked about garages not being air tight and communicating air with crawlspace and interior space?!?). My fourth clue was degrading or already deteriorated rim joist, I-joist ends, and sill plates around the perimeter of the structure. Only along the perimeter of the structure in these areas.

If you had a probe, and lightly poked, you would find this wood readily gave

Some Science

Wood is comprised of polymers (like most things, glucose is king at the molecular level for form and energy). Some of those polymers form cellulose and lignin, the two components that help wood in its natural form withstand biodegradation for an extended period in the natural world. However, we’re talking processed wood here and wood that has had moisture removed (and likely some of the lignin) as part of the engineering process. If you take out the water in the wood fibers, then the degradation slows down even more. Guess what happens if/when you reintroduce continued cycling of wetting to those same wooden fibers that were mechanically dried out? If you said it speeds up the microbes that “eat” the wood, you are correct. Additionally, we get oxidation of the wood fibers which lends to the very darkening of wood coloring. Oxidation also is a decay process. **See this 2011 MIT paper for a brief explanation of wood and moisture.

Does Your Brain Hurt?

Okay. Okay. Let’s jump ship from chemistry. I usually don’t bring up chemistry with clients or in field reports because it’s confusing and usually unnecessary. And in truth, I usually have to “refresh” my own understanding routinely. The simple explanation fits well – you can’t take a material that was intended to be dry post-processing and allow it to repeatedly get wet. It degrades and anything it was supporting no longer is supported as well. Ergo, you must protect this dry product and keep it dry. Dry from the exterior wet world and dry from the interior (crawlspace) wet world. When you fail at this, the material(s) fail and you get unhappy homeowners, or shocked buyers who no longer want the otherwise pretty home.

All of this – and I mean all of it – could be avoided by well-executed flashing. But, then again, you can’t execute flashing installation well IF the installer doesn’t understand the basic principles of building science and why they should flash, where they should flash, and how the flashing should be designed (ahem, to shed water…).

I’m not the best artist, but you can “see” the idea here — if the home had this flashing, there wouldn’t be this problem so early in it’s life.

A Moment With Unvented Conditioned Attics

Our eyes are amazing organs. They filter something we can’t otherwise perceive and allow us to perceive the worlds which we see. But, what happens when we pay for a service that addresses what we can’t see with our eyes? How do we know we are getting what we pay for? Or, if we’re the contractor, how do we really know what we’re doing is effective?

We test.

In our middle TN region, we don’t have many homes that are built with unvented conditioned attics, or are converted to unvented conditioned attics. To my knowledge, we also don’t have a hardy education for trades professionals regarding the building science behind vented unconditioned attics vs. unvented conditioned attics. So, our line of ignorance places us in a precarious position as home owners and builders.

In our region, what I see mostly is low density open cell spray foam installed along the roof line and eaves. In theory, this closes off the attic from the exterior environment extending the interior enclosure from the finished ceiling to the now-foam-filled roof framing. In theory.

In actuality, because our trades professionals aren’t regulated in relation to the depth of the installed low density open cell spray foam, often there are irregularities, voids, and gaps. These, individually, are no big deal. But taken as one larger whole (get it…?), they are a very big deal. Thermal imaging helps us see this clearly.

Further Complication

In addition to no real standardization of installation and resulting thermal intrusion and potentially moisture issues (for our immediate market), we would naturally need to worry about moisture issues anyhow. The biggest potential issue for unvented conditioned attics is moisture. Per this article by Joseph Lstiburek and Building Science Corporation, moisture is the most pernicious concern for unvented conditioned attics. Why is this so complicated?

Low density open cell spray foam in an unvented conditioned attic

Installation is key — the bright yellow indicates thermal inefficiencies which indicate questionable installation

Well, if it’s a new home, then there is moisture from the building materials. If it is an existing home, there is moisture (in our market) from deficiencies related to poor water management and indoor air quality. And then there’s our subtropical environment that tends to be hot, wet, and humid. This is why some building science folks argue for use of high density closed cell spray foam only — it blocks moisture getting to the roof sheathing/decking a bit better (when properly installed). But, it carries it’s own pitfalls.

So What’s To Say

In the end, I put my money where Lstiburek puts his decades of experience and knowledge — the man is a compendium of building science experience and testing. So, if you ask me I will tell you low density open cell spray foam is acceptable when properly installed. The problem, as this photo from a recent new build shows, is installation. Now, this particular home has an in-line dehumidifier in the basement which should help. I recommended further monitoring via hygrometer installation in the attic as close to the ridge line as possible. If the moisture loads are noted to be beyond ideal percentages, then the client can manage the unvented conditioned attic space in one of several ways. Lstiburek’s recommendation for balanced ventilation would be sweet to see, but in our region I suspect it might be too complicated for many professionals to get right without causing more harm. FYI, that article also has great information on walling and basement configurations, too. If that kind of thing tickles your fancy.

And So The Testing Begins, Sort Of …

Sorry You Got Lost :)

If you stumbled your way here, I’m sorry. But, not sorry. You should know I color myself humbled in relation to others in my profession. The thing about building science is there is always a new way to “see” something and always someone else who can “show” you something new to see.

While home performance testing is pretty straight forward, there is guess work involved and it isn’t always a hard science. Additionally, some of the set standards referenced in the industry don’t necessary have a poignant or purposeful origin. Home diagnostic testing becomes even less “hard science” as often you have to look at the system as a whole in order to find the chink in the armor. Yes, there are common and routine causes and known issues. But, each structure can be unique and so needs to be “seen” in a unique, open-minded manner that fits the client’s requested solution(s).

Let’s Have An Example

As an example, indoor air testing has been all the rage in recent years. There are oodles of products available on the marketplace for home owners, as wells as professionals. However, when we get a call for “mold” testing, I feel we have a responsibility to not just sell someone on a test to make money. The truth is, sometimes air testing is relevant and helpful to determine a particular contaminant. The bigger picture, however, is listening to what’s really being asked and then have a conversation regarding spending time reviewing structure systems to determine a deficiency and/or cause. In then end, does it matter knowing what’s in the air specifically for hundreds of dollars (the tests we use cost between $200 and $350 just for the test), or could we do other diagnostic work (that’s fancy speak for using our education, experience, and some shiny tools) and come away with a list for guiding repairs and/or modifications (read — resolution)? All a test will tell you is what you have in the air, and there are no agreed upon standards for concentrations, limits, or significance. And let’s not get into the quandary of knowing lab standards and practices…

Ruminate For Action

In the end, what you may need for your structure — be it commercial, or residential, or hunting cabin, or storm shelter — isn’t necessarily every test in the world thrown at it. Sometimes, the best answer may start with knowing how to ask “why?” Why is this happening? That’s what TNergy Services does for you and that’s where we start. Sometimes, you literally need a blower door test (new homes, e.g.); sometimes a blower door would be silly to perform when what you need is a site assessment to identify system deficiencies causing water (usually always water) related issues. We’re really good listeners. We’re really happy thinkers. We’re pretty good communicators. Give us a ring and let’s see how we can help make your home/business perform and “feel” better.