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Veneer brick needs flashing!

1/9/2013

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In the past, materials used for structural purposes often served a number of different functions.

Consider the humble American log cabin. The log walls provided structure, insulation, and the finish for both interior and exterior surfaces. Brick was even more varied in use. In buildings it gave us structure, insulation (a little), and a finished surface for walls, floors, and in some cases, even ceilings.

People generally perceive brick as a high quality, historical material. For most of us, it emotes durability and strength. This is partly what drives its use in residential architecture.

Today, even though we don't build structural brick walls any more, we do build houses to look like they were built with two or three wythes of brick. As the saying goes, perception is reality.

In the post-World War II boom, builders began to use brick as a veneer---as an
exterior cladding. They abandoned structural brick in favor of concrete block
and dimensional lumber. Brick is now laid in a single wythe (or course), and
attached to the structural wall with metal brick ties. Bricklayers leave a 1" gap between the brick and the structural wall, to help with drainage and prevent capillary action.

There are some important distinctions between veneer and structural brick.

First and foremost, you need to understand that veneer brick does not act like a drainage plane. Rainwater can and will pass through a veneer brick wall. And it will do so on a regular basis. So where does it go? Most often, it drains down the back face of the brick, until it finds a ledge---like a window, or a roofline, or the foundation. If that ledge is properly flashed, it will then exit the wall.

Unlike structural brick, veneer brick needs flashing to do its job. Flashing takes the water that finds its way behind the brick, and sends it back out to the front face. It's like a built-in guttering system. If there is no flashing, you will probably encounter problems---water entry, rot, or mold.

Second, veneer brick is a reservoir cladding. That means it can absorb and hold a great deal of water. In the summer, a heavy rain followed by sunshine can drive a lot of moisture into your house (this is called inward solar vapor drive). If your walls do not have an adequate vapor barrier, your air conditioner will have to work overtime to remove this excess humidity.

Sadly, many of the brick houses built in the Shenandoah Valley are missing a weather resistant barrier, do not include flashing, and they lack weep holes.

As an example, I've attached a picture of a recent remodeling project. When I opened up the ceiling cavity, not only did dried mortar drop all over my head, but I found an unpleasant fact: the builder had failed to follow even the most basic principles of veneer brick construction. As a result, water finds its way into the house, and the owner has a permanent brown spot on her first floor ceiling.

Short of tearing down the entire brick wall, there is no fix.

Problems with this brick installation include:

1) The brick was laid below the roofline (where the garage tied into the main house structure).

2) There is no "through the wall" flashing above the foundation, the windows, or the doors---or any flashing for that matter. Although the builder installed a weather resistant barrier behind the brick, it doesn't tie into any flashing.

3) There are no weep holes (which kind of goes without saying, since weepholes are only effective when tied into flashing).
Picture
On this wall, brickmasons had to lay the brick between the house wall sheathing and the garage roof truss. Note the Typar (weather resistant barrier) peeking out from underneath the steel brick ledge. Where does all of the rainwater go?
If you are considering buying a brick house, make sure you understand the difference between structural brick and brick veneer---and make sure that your home inspector knows the difference.

If you are considering building a brick house, make sure your builder plans to follow the construction details established by the The Brick Industry Association. This will ensure your house doesn't experience moisture damage at some later date.
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Acronymical Confusion

1/3/2013

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Although some parents still use alphabet soup it to help their toddlers learn letters and spelling, it is not as popular as it was years ago. I wonder if it because adults are getting a heavy dose of alphabet soup everytime they read a newspaper or magazine or online blog? If you are like me, you are overwhelmed by the sheer number of acronyms you encounter.

Although acronyms are supposed to make it easier to learn a new set of words, I think we are starting to suffer from acronymical confusion.

Some of these acronyms have been with us a long time, or they have been popularized through various media. I'm quite sure you are familar with the YMCA. You may even be a member. And I have little doubt that you know about the CIA, EPA, and FBI. However, you are probably not familar with the growing number of "green building organizations" and standards that have sprouted in the last twenty years. 
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In this blog I will provide a brief overview of several popular green building standards. You should note that these programs are in a process of continual revision; what is true today may not hold for tomorrow.


LEED (Leadership in Energy and Environmental Design)

Organization: USGBC (U.S. Green Building Council)

Summary: Perhaps the most recognized green building standard, LEED is a comprehensive standard that covers just about every aspect of construction. It is a sliding scale system. Although you must meet a certain number of points to earn the certification, there are several levels: silver, gold, and platinum. Although it emcompasses both residential and commercial construction, its primary focus is multi-family and commercial projects.

Pros: It covers a broad range of issues, from location efficiency and pollution reduction, to stormwater management and regional material use. It even has a category for bird collision deterrence.

Cons: Critics argue that it fails to adequately address energy efficiency, or that it has encouraged "glass box" architecture. Unsubstantiated energy efficiency claims was even the topic of a $100M class action lawsuit (dismissed in court). The level of documentation required makes this standard cumbersome and expensive for residential projects.


ENERGY STAR

Organization: EPA (Environmental Protection Agency)

Summary: A program of the U.S. federal government, this program focuses on reducing energy use in homes. Certified projects must pass either a prescriptive path or a performance path.

Pros: The name is widely known for its association with energy efficient appliances, and has solid branding because of consumer recognition.

Cons: In years past, critics said that the program lacked any teeth, that it was too easy to meet the standard (performance monitoring of certified houses showed marginal savings). A recent update, Version 3.0, is more rigorous.


EARTHCRAFT

Organization: Southface Energy Institute

Summary: This standard focuses on reducing the consumption of resources, energy, AND water. It applies to new homes, multi-family housing projects, and light commercial construction. Certified projects must pass a number of criteria and tests. The organization says that Earthcraft houses are projected to save 30% compared to code-built houses.

Pros: This standard covers a number of issues, and it does so without adding a lot of complexity to the building or certification process. It focuses on issues that are specific to the Southeastern part of the U.S. It has the backing of the U.S. Department of Energy, as well as the Environmental Protection Agency.

Cons: This standard does not address all aspects of sustainable construction. Also, it is only available in the following states: VA, NC, SC, TN, GA, and AL.


PASSIVE HOUSE

Organization: PHIUS (Passive House Institute US)

Summary: An offshoot of the German based Passivhaus concept, this standard focuses mainly on reducing heating and cooling loads (although overall energy consumption must also meet a strict limit). Certified consultants must model the project using a complex spreadsheet, then test for certain criteria.

Pros: It is one of the most rigorous standards for energy efficiency. Savings are projected to range from 60-70% compared to code built houses.

Cons: The standard only addresses energy consumption. It ignores other issues related to green building. Critics argue that the standard lacks any feedback on cost efficiency, and that it is excessive for some parts of the country.


Other standards include:

LIVING BUILDING CHALLENGE
Organization: ILFI (International Living Future Institute)

ICC-700 NATIONAL GREEN BUILDING STANDARD
Organization: NAHB (National Association of Home Builders)

Regional programs are available too. Literally, there are dozens of local green building programs. Some localities are requiring builders to rate new houses using the RESNET developed HERS Index:

Picture
Stuffed yet? Suffering from information overload? Sick of alphabet soup? Me too. All of these organization and standards are giving momentum to good ideas, but they are sometimes difficult to digest.

With our society's level of sophistication, it is hard to image that this will ever become a simple topic, or that organizations will stop using acronyms. So I'll leave you with one more: KISS (Keep It Simple Silly). For designers and builders of high performance homes, the KISS principle still applies.

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*We have Franklin Delano Roosevelt to thank for being the first to prepare a linquistic feast of acronyms. Back in the '30s, when FDR rolled out the New Deal, reporters struggled to deal with the huge number of new government agencies formed by this legislation. Sarcastic observers started calling them the alphabet soup agencies. Today, these agencies are quickly becoming TNTC (Too Numerous To Count ;)
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    Daniel Ernst

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