How safe is your house from water damage?

My neighborhood listserv is ablaze with people asking for help with repairs due to water damage. The recent rains are a good reminder that Austin gets an average 32.5" of rain every year, which is to say that our buildings are pretty susceptible to rainwater damage. It's common sense, yet, everyday I see houses built using risky construction details and building designs that ignore this significant element of our weather. How you deal with bulk water* at the roof, walls, and foundation (near grade) is very important to the durability of a building. If you are in the process of building your house, pay close attention to the weak spots identified below.

Water Intrusion at roof:

Most people recognize that roof and grade are obvious areas of weakness, when it comes to water intrusion. You've probably lived in a house that has had a leaky roof, most likely leaking around the chimney during a storm. Even if it's not literally dripping water from the ceiling, but just a wet patch or a watercolor stain, you've got a problem on your hands.

Water Intrusion at or below grade:

Perhaps, you live in a house that got flooded in the recent torrential rains. Yes, that was a lot of rain. But, if storm water accumulates outside your house in a downpour and gets precariously close to coming inside, then you may very well have a drainage problem on your lot, or your floor/ slab is not high enough. I've lived in that house and it's not fun.

How about the crawl space under your house that is a pond in a rain event. What about your damp musty basement?

But walls?

Just think of all the people who walk out in the rain with a small umbrella and rain boots to protect them from getting wet. They've covered their bases - doesn't matter that their leggings are getting sprayed a little. Now imagine that you're wearing an expensive suit or a special outfit to dinner. Or you're going to be out in the pouring rain for a long time. You'd make sure you wear a trench coat and use the biggest umbrella you've got, wouldn't you?

The one good thing about the drought that prevailed over central texas for over 3 years was that our buildings didn't age as much. Because unlike human skin, which ages faster in the absence of moisture, building skins age faster in the presence of moisture. So if you are wondering why your house that was built in 2012 looked great for 3 years and now it looks like @*&#, then you've probably got unprotected walls that are aging from getting wet.

Water intrusion at walls:

The most commonly used exterior building materials such as stucco, brick, and stone do not repel water, but instead they absorb and hold water like sponges. That's why you see growth of mildew, algae, lichen, moss, fungus, etc on masonry walls that are exposed to rain. Not only is this a high-maintenance situation from an aesthetic standpoint, it's recipe for water damage to the innards of the wall.

Notice in both examples, that the part of the stone veneer that has water damage is at the base - the part most unprotected by an overhang. The umbrella isn't big enough. The taller the wall, the bigger the umbrella has to be. Also notice that these walls are more exposed because of their slope/ angle i.e. they are not vertical.

A good power-washing will take care of the mildew and unsightly discoloration on the stone. But if there is any wood framing behind that stone, it needs a good weather barrier and flashing at the base to protect from rot. You need a good trench coat.

In the pictures below, it's very clear what areas of the wall get the most water - it's where the water runoff from the roof hits the wall. Gutters that direct the water away from the wall are highly recommended. Also, the larger the roof area, the more the runoff - so size the gutters to handle the amount of water.

 Water intrusion at openings:

The condition is worse when there is an opening in the wall, such as at a window or a door. The picture below shows a very common condition - where roof runoff hits the corner of a window. How long until there is water damage behind that path of water? Even if the window flashing is done well, this is condition that tests the limits of the materials and installation. It's risky.

Water damage at openings

Best Practices:

There is no single solution, but mainly to acknowledge that rainfall is part of our climate and design for it. Include redundancies. Design a large roof overhang, avoid flat roofs, install correctly sized gutters, avoid large expanses of walls and unprotected windows, a good weather barrier installed shingle style, coupled with through-wall flashing and flexible flashing membranes around openings. If you can afford to, cover the wall with a material that sheds water - materials like metals or other large panel products.

*Bulk water - water damage vs. moisture damage

Most of the water damage and moisture damage in buildings occurs from 'bulk water intrusion', the main source for which is rainwater. Other sources being plumbing failures.

'Bulk water' implies large amounts of water, whereas 'moisture' implies trace amounts of water.

When left alone, both can cause significant damage in wood frame buildings. It's the rate of damage that varies. Depending on where the intrusion occurs and how much water enters, it may manifest immediately as a leak (as in dripping water) or wetness, OR it may take years to manifest. Typically, the longer it takes to manifest, the worse the damage. As we all know, we take immediate action when there are extreme conditions such as a leak, whereas a stain on the ceiling takes less priority in our busy lives.


No matter how well built your house is, you need a maintenance plan to keep things from getting out of hand. Question is, would you rather have a low maintenance house or a high maintenance house?




'Tis the season...for allergies - Indoor Air Quality

A few nights ago, I woke up in the middle of the night with a terrible feeling that I couldn't breathe.  Very soon I realized I had a terribly stuffy, itchy nose, and a sore throat.  I've been suffering from these symptoms for a few days now.  While everyone in my household has taken a turn at a viral fever over the last few weeks, I know for a fact that I am suffering from allergies, not a viral infection. It's that time of year again, when environmental airborne allergens are high.  Having lived in Austin (the allergy capital of the world) for 15 years, I am very familiar with seasonal allergies, especially sniffles caused by hay fever and cedar fever.  I myself developed nasal allergies just a few years ago.  For me, it usually starts in late December/ early January, when juniper (mountain cedar) pollen is at it's highest, and continues through late spring, when oak pollen abounds, and everything in the city is covered in yellow dust.

Austin Allergy Calender

Of course, most people start out experiencing allergies in one season, that then expands to two seasons, and soon they have year round allergies.  All too common in Austin.

So, if you call Austin home, and you are allergy-free, count your blessings!  Also, make the most of it, because, rumor has it - there is a high probability that you will be under an allergy attack in a few short years.  And then, brace yourself!

Along with my nasal steroids and anti-histamines, I arm myself with an app on my phone that alerts me on the allergen of the day and it's count.

This time, the culprit is mold.  Mold is a perennial allergen that thrives in moist conditions that are prevalent outdoors after rainfall or indoors in wet areas.  Mold sporulates in the darkest hour of the night, as opposed to pollen which is highest in the wee hours of the morning (which explains why I woke up feeling suffocated at 2am).

Mold - allergy count in Austin

Is your indoor air cleaner than outdoor air?  When outdoor allergens are in the red zone, the common recommendation is to stay indoors.  But the truth is, you are not as protected indoors as you would think.

There is plenty of exchange of air between the inside and outside of a house, even when your doors and windows are closed.  The older the house, the higher the chances are that the inside is not sealed from the outside.  Even houses that are built today are not as airtight as they could be.  There are gaping holes in the walls, ceilings, and roofs.  Vents, lights, plumbing and electrical penetrations, gaps around windows and doors, fireplace chimneys, connections between different materials, etc, all puncture the in-out barrier and unintentionally let the outside in.

Moreover, the mechanical system is (intentionally) mandated to bring "fresh air" from outside into the house to meet ventilation requirements.  This air is seldom treated or controlled.

Then, there are the allergens generated inside the building - dander, dust, mold, etc.  All this affects the quality of your indoor air.  There are visible and invisible particulate matter suspended in the air you breathe.  There are also chemical contaminants, which is another topic.

What is and what should be. Your air-conditioner is supposed to "condition" the air that it circulates through the house.  Condition, meaning to clean and disinfect, in addition to cool and dehumidify.  But most a/c units, specifically mechanical systems installations, are designed to do one thing most effectively, and that is, cool the air.  The rest is done inadequately.

For effective results, it's a good idea to take care of each task of air-conditioning separately.  So, if you are replacing your indoor air handler unit, you have an opportunity to upgrade your system.

The best way to make sure that air recirculated by your air-conditioner is clean, is to get the best filter you can afford.  Look for a thick pleated (accordion) air filter with a High MERV (Minimum Efficiency Reporting Value) rating (ranges from 1 through 16).

The last time I upgraded my system (previous house), I got an 7" thick pleated MERV 10 filter, located in the air handler unit, in addition to the filter at the return air grill on the wall.

The filter is the first (and sometimes only) line of defense.  It blocks particulate matter before it enters the air handler unit, thereby limiting the debris on the evaporator coil and blower inside the unit.  Dirty coils and blower leads to efficiency loss and also contamination of condensate pan below, which then leads to clogged drain lines. Imagine a dirty broth at the bottom of your unit (inside).

There are other techniques and products available to purify and disinfect air.  Selection depends on target - UV lamps, adsorption, Ionizers, Ozone generators, etc.

Maintenance My allergy attack reminded me to replace my AC filters.  And it was as yucky as you can imagine.  Unfortunately, I only have the protection of a regular 1" thick household filter at the return air grill in the wall.  I sorely miss the 7" thick pleated filter at my old house.  I would have liked to clean out the condensate pan, but the drain line coming out of my AC unit was not set up to allow that (i.e no clean out, T-fittings, or valves).

When was the last time you did any house keeping or maintenance on one of the most important systems in your house - the one that is controlling the air you breathe? (This is not a guilt trip?)

If you haven't already done so:

  • change the air filter at each return air grill in the wall or ceiling, every 3 months
  • if you have a thick pleated air filter at the unit, replace that once a year
  • if you have a UV light in your return air chase or inside the unit, change it out every 2 years
  • clean out condensate pan and drain line, once a year with bleach water (if you have the right set-up)
  • set up an annual a/c maintenance and they can take care of all of the above along with other stuff

Building new?  If you are building a new house right now, take a step back and discuss your indoor air quality, especially if you suffer from environmental allergies.  How are you preventing outdoor air pollutants from entering your house?  And what are you doing to mitigate indoor air pollutants?

You may not have allergies, or asthma, or any related health issues now, but what about the future? What about your kids?

Your health and comfort are at stake.  It pays to take a comprehensive approach to the design and construction of the entire house, in addition to thoughtful design and installation of mechanical systems.



AIA CRAN Symposium - A professor, an architect, and the green police

I was in Minneapolis last week, attending the 2015 American Institute of Architects Custom Residential Architects Network (AIA CRAN) Symposium, "Elevating the Art of Residential Design and Practice". I was CRAN last year and have to say that this years talks were well-rounded and very relevant to modern day architectural practice.

I particularly enjoyed the following three lectures that discussed sustainability and green building.  A professor, an architect, and the green police presented:

  1. How the Collaborative Economy is Transforming Housing, by Thomas Fisher
  2. Integrated Green Design: High-Performance Design Strategies for Building Design & Construction, by Peter Pfeiffer
  3. A Review of Green Building Products & Systems: Green Washers Beware!, by Michael Anschel & Carl Seville

I'm told, these lectures will be available on soon.

How the Collaborative Economy is Transforming Housing by Thomas Fisher

The 30,000 ft view: Fisher's talk gave the big picture, the long term projection.

The gist: Architecture, architects, and the future - the status quo is unsustainable.  Sigh!

Tom Fisher identified the four drivers for the paradigm shift in the way we live, work, play, travel, create, learn, bank, and consume - Technology, Values shift, Economic realities, Environmental pressures.

He spoke about:

  • the current trend towards a peer-to-peer/ sharing/ collaborative economy (Kickstarter, Uber, Getaround, Lyft, Airbnb, etc)
  • Driverless cars and how that's going to change our cities
  • Millennials, who are looking to live in downtown and the inner city, because they value experiences more than the idea of buying a single family home with a big yard out in suburbia
  • the third industrial revolution of mass customization
  • our ponzi scheme with the planet

While he made some very salient points, pardon me, I don't share in his prophecy of doomsday and collapse.  I have since listened to several of Fisher's lectures (available online), and I'm afraid they all carry the same Malthusian critique and predict the downfall of our world and planet.

On the contrary, I think we humans are an ingenious bunch.  Most individuals and systems make life and our world better.  If you don't share my optimism, check out

No doubt, driverless cars are going to change our lives.  If people are willing to spend 1 to 2 hours per day driving to work now, I can't help but think that driverless cars, along with home delivery meals, and telecommuting will only exacerbate urban sprawl, not alleviate it.  Better services and infrastructure will incentivize people to live further away from town.  If the industrial revolution gave birth to cities, the third industrial revolution is going to spread population out, along with wealth.  P2P and sharing economy is leading to horizontal distribution of wealth, and generally millennials are wealthier than their parent's generation.  It may be true that millennials value experiential purchases more than material consumerism.  But, once they start having families, do you think they will want to live in crowded expensive inner cities when they have a choice to live elsewhere.  Heck, they will be wealthy enough to own secondary lakeside (or other destination) vacation homes that their driverless cars will take them to (as they relax and watch a movie in transit, no less).

Integrated Green Design: High-Performance Design Strategies for Building Design & Construction by Peter Pfeiffer

The 3000 ft view: Pfeiffer reviewed his thoughts on green building through his lens as a practical architect.

The gist: Design like you give a damn about the environment and green-by-design is more economical than green-by-gizmo.

Full disclosure - I was a Project Architect at Pfeiffer's architecture firm for more than 8 years.  Suffice it to say, I subscribe to the philosophy of green-by-design (passive first, active next), and know a thing or two about high-performance buildings.

Pfeiffer talked about the benefits of high-performance buildings.  As always touted, reduced environmental impact and consumption; but equally important, improved health, enhanced comfort, and low cost of ownership.

He also presented the green design pyramid, which follows the logic of the food pyramid.

Green building pyramid

  1. Design for Climate (the base): Design decisions and choices made early in the project (pre-design or schematic phase) provide maximum impact for minimal cost. For example - site selection, siting and orientation (responsive to climate- breezes, sun/shade, views), programming and zoning (for a/c), house sizing, etc are passive strategies for a more energy efficient design.
  2. Building Science and energy conservation: Building envelope design (roof system, insulation, wall system, glazing, etc.), HVAC specifications, water saving fixtures and appliances, energy efficient light fixtures and appliances, material selections, etc
  3. Energy production (the top):  Also called "green bling", this tier includes photovoltaic arrays, solar hot water, geothermal, and wind turbines that generate power/energy and get you closer to net-zero.  Even with the federal (and city utility) tax rebate, this bling can set you back several grand. They are the cherry on top or lipstick on a pig, depending on the project.

One would think that is an easy sell to a group of architects.  It puts more power into the hands of the architect, the inspired generalists, and positions us as leaders of green building.  And yet more builders and product manufacturers command that space than architects.

A Review of Green Building Products & Systems: Green Washers Beware! by Michael Anschel & Carl Seville

The 300 ft view: Up close look at the green building products available on the market.

The gist: Don't get caught up in the hype; know your building science.

Anschel and Seville (the Green Police duo) talked about green washing and presented the 8 sins of green washers: lack of proof, worshipping false labels, vagueness, false conclusions, hidden trade-offs, fibbing, lesser of 2 evils, irrelevance.

Building green is a matter of juggling the following: site impact, community impact, resource efficiency, water conservation, indoor environmental quality, energy efficiency, durability and maintenance, ease of use, practicality of installation, noticeable improvement, and last but not least, beauty.

If you are lost in the quagmire of green building products out there, a) you are not alone, b) look into using Pharos Lens to make more informed choices, and c) try not to get hung up on the products, unless you have particular health concerns or sensitivities.

There's also this documentary film (Greenwashers), which is now on my watch-list.

Just remember, there are 50 shades of green and you are damned if you do, and damned if you don't.



Guthrie Theatre, Minneapolis