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Brick and Other Exterior Masonry: Not a Great Choice for Our hot humid climate

 In this project, we used wood and brick siding to not only promote green building, but to also reduce the thermal mass of the house, to cool the temperature of the home.

In this project, we used wood and brick siding to not only promote green building, but to also reduce the thermal mass of the house, to cool the temperature of the home.

Don’t you love the look of Austin stone on a home? Many neighborhoods in Bryan and College Station require a high percentage of brick or other masonry products on the exterior of their homes. It is a great look but not a great approach, especially if you are interested in green building or even just reducing your utility bills.

Brick and other masonry products are known as thermal mass. Thermal mass is the ability of a material to absorb and store heat, in this case, your siding material’s ability to absorb that heat.  In other words brick heats up all day and disseminates that heat to the house.

But, you may be wondering, what about adobe? Adobe is used in hot dry climates, not hot humid climates. The difference is that in a dry climate, temperatures cool down at night. The heat absorbed by the adobe does not make it into the house before it is cooled by the night air.   Water in the air also serves as somewhat of a thermal mass, holding heat longer than dry air, which is what keeps or night time temperatures higher than in the desert. 

The vernacular architecture of hot humid climates usually feature siding for a reason. But, if you are stuck with neighborhood controls requiring a high percentage of masonry or if you just like the look of stone, there are some things that you can do mitigate the negative impact of a thermal mass. 

Perhaps the most effective thing to do is use a veneer stone which is much thinner than traditional stone. Also try to avoid masonry on the west side which tends to get more direct sunlight at the hottest part of the day.  Want to learn more about siding that we recommend. For even greater shading use larger than normal overhangs where possible. 

As always, use landscaping as a design element for beauty and function. Deciduous trees on the west provide crucial summer shading while allowing the sun through in the winter.  

Brick can also create moisture and potentially rot problems if a proper drainage pan is not created behind it. Of course any cladding can become a problem without proper moisture sealing. This is an area that you should question a builder about before hiring. There are no requirements in Texas for builders to have knowledge of building science and this is a place that lesser builders tend to get themselves into trouble.  

Siding Profiles

Siding Profiles

At Stearns Design Build, we are big fans of siding; well some siding. One of the reasons that we like siding so much is because it is a big part of our vernacular architecture in Central Texas.  Another reason that we like it is because of the problems with its alternatives; brick or stone.  While those materials can be beautiful, they are a thermal mass acting as a big solar collector adding heat to our homes in the summer. It is unfortunate that so many neighborhoods require a majority of brick and stone.

Like most building techniques, the details are essential to a good siding application, and, more often than not in new construction, corners are cut.  When siding is replaced there are ample opportunities to do the job right and make a difference in the performance of the home.  In this series we will review our two primary siding details explaining the pros and cons of each.

In the Typical Siding Profile  we will detail the least expensive application.

In the Rainscreen Profile  we will detail how we provide a rainscreen behind the siding.

While the typical profile may be the least expensive to install, it is not necessarily that best value as the otherapplication works to increase energy efficiency and durability.

Image Courtesy of James Hardie  Alliance

Siding Profile with a Rainscreen

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Siding works best when there has air movement behind it.  We can accomplish this with something called a rainscreen.  This is simply placing siding on a lath strip, holding it out from the wall so that water can drain and air can move.  A rainscreen will help both the siding and the paint on a home last longer. We feel that it is a mistake to leave the rainscreen off when placing wood siding.  It is also highly recommended for fiber cement siding.

When replacing siding we usually remove everything down to the framing. This allows us to inspect and fix the insulation.  This includes caulking the base of the wall whereby reducing air leaks. Occasionally there will be rot or other defects that will need to also be repaired.

We always use structural sheathing on the outside of a wall. Structural sheathing is made from wood and when put under stress, the nails that hold it will fail before the sheathing does.  This has the effect of turning the wall into a beam.  Consequently, this is a good idea anywhere, but especially here; as we have expansive clay soils that often cause foundations to move.  By using solid structural sheathing we create a much stronger house that will hold up even when the earth moves.

A product called house wrap is then placed on top of the structural sheathing. This acts as a moisture and air resistive barrier that protects the house.  However, many house wraps allow too much air and moisture through as a result of our hot, humid climate.  As a result, top of the line, Tyvek brand house wrap, is specified on all of our projects. The house wrap must then be taped at all of the seams and at the top and bottom of the wall.  This is a crucial step in properly air sealing a home. It is important to use tape that has been specifically formulated to adhere to the house wrap used. Application of house wrap around windows and doors is somewhat intricate and each step is fundamental to a well functioning house.

The rainscreen is formed by using lathing strips that hold the siding out from the wall.  We place a screen along the bottom of the wall where the void has been created by the rain screen to allow air in and to prevent bugs from getting in.  There is also a screen placed along the top edge of the wall to allow air to escape.  In addition to keeping the siding dry, this air circulation helps reduce heat build up.

Proper application of siding requires a lot of attention to detail. Siding is supposed to be fastened to the lath.  However, most often we see trim placed directly over the siding. While this is a much faster way to finish a job, it is a significant compromise to the overall aesthetics of a project and especially to the way the home is protected from wind, water and humidity.

It is not uncommon to see window and door trim run in ways that will cause leaking. Failure to properly install metal flashings is another cause of water penetration.

Also see:

Typical Siding Profile

Typical Siding Profile

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profiles1

A typical wall profile in the Brazos Valley starts with drywall on the inside; then a 2X4 wall with R-13 fiberglass insulation between the framing members. On the outside of the 2X4 wall is nonstructural sheathing and then the siding.

When replacing siding we usually remove everything down to the framing. This allows us to inspect and fix the insulation.  This includes caulking the base of the wall thereby reducing air leaks. Occasionally there will be rot or other defects that need to be repaired.

We always use structural sheathing on the outside of a wall. Structural sheathing is made from wood and when put under stress the nails that hold it will fail before the sheathing does.  This has the effect of turning the wall into a beam.  This is a good idea anywhere, especially here, as we have expansive clay soils that often cause foundations to move.  By using solid structural sheathing we create a much stronger house that will hold up even when the earth moves. It is also much more resistant to high winds.

On top of the structural sheathing goes a product called house wrap. this is a moisture and air resistive barrier that protects the home.  Many house wraps allow too much air and moisture through for our hot, humid climate.  On our projects we specify top of the line Tyvek brand house wrap.  The house wrap must be taped at all of the seams and at the top and bottom of the wall.  This is a crucial step in properly air sealing a home. It is important to use tape that has been specifically formulated to adhere to the the specific house wrap. Application of house wrap around windows and doors is somewhat intricate and each step is crucial to a properly functioning house.

In this profile, on top of the house wrap goes the siding.  Proper application of siding requires a lot of attention to detail.  Most often we see trim placed directly over the siding. While this is a much faster way to complete a job, it is a significant compromise to the overall aesthetics of a project and especially to the way the home is protected from wind, water and humidity.

It is not uncommon to see window and door trim run in ways that will cause leaking. Failure to properly install metal flashings is another cause of water penetration.

We call this our typical siding profile because it most closely mimics what is common in our area. But by adding just a few extra steps and using higher quality materials we are able to achieve a much better looking and longer lasting siding installation.  It should be noted that this is not our most highly recommended siding profile and it is a profile that we strongly discourage for wood siding, which needs airflow behind it to be durable.

Also see:

Siding profile with a Rainscreen

Six Signs Your Siding or Exterior Trim May Need Replacing

There are few home repairs more thoroughly ignored than failing siding and exterior trim.  This may happen for several reasons.  Many people simply do not notice – out of sight out of mind.  There is often a perception that the exterior of a home is invincible, however, even brick homes have trim that can fail. Or it may feel too big and confusing to handle. In addition, the cost can be intimidating – never mind that waiting will just make it more expensive. This is not a repair that should be ignored.  Dealing with siding issues early on will save time and money.  When siding fails bad things happen, much of which cannot be seen. Left unattended, siding and trim failures will eventually bring a building to the ground.  Our homes, unlike the great structures of yore, are made primarily of biodegradable materials.  Though they are unlikely to last millennium, if well cared for, they can certainly last generations.

Here are six specific problems that you can look for.

Or you can just call us for a for a Free Siding Consultation at 979-696-0524 or arrange to have us call you.

1 – Rot

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Here in College Station and Bryan we live in a hot, humid climate that is unkind to wood and paint.  When the paint fails, wood is exposed to our harsh climate conditions.  A small paint failure will allow water to get to wood, which in turn will speed up paint failure. This will eventually lead to rot in the wood.

Rot is a self-exacerbating condition.  As wood rots, it softens and is able to hold more water, which encourages rot to spread faster.  This is why it is important to deal with rot issues as soon as they appear.  If caught early, repair is possible. However, if left unattended, replacement becomes the likely scenario.

Rot frequently hides under gutters, behind metal trims and at hard to see roof intersections.

2 – Frequent Painting Needed

If your paint is not holding up as long as you feel it should, this may be a sign your siding or trim is beginning to soften and may need replacing.  In the hot summer, moisture trapped in the wood will try to escape pushing at the film of paint on it.  Once the wood begins to soften it can hold more water building up more pressure behind the paint.

3 – Poorly Installed Siding

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In our region, the people who build the frame of a house are usually the ones who put the siding and exterior trim on it. Framing a house is a fast process that does not require close attention to detail. However, siding and trim do.  Because those doing the work tend to be less detail oriented, important details often overlooked. Siding is frequently run too close to the roofing, protective flashings are often left off and trim is run on top of the siding rather than bringing the siding to the trim. These are just a few of the many application problems that we most often encounter when residing a home.

4 – High Utility Bills

There are many factors that can lead to higher than necessary utility bills. Key among them is how well the envelope of the house is protected.  In the Brazos Valley, heating and cooling are our biggest utility costs.  The interface between the space that we are conditioning and the outdoors is a large part of what determines how much energy we will have to use to heat and cool.  The two big variables are air infiltration and insulation.

Air and moisture infiltration are significantly handled by the application of siding and trim.  When corners are cut, which in new home construction they usually are, bad things happen.  Consequently, when siding is replaced it is an opportunity to tighten the house and reduce air and moisture leaks.

The opportunity for improving insulation when replacing siding may seem less obvious, but it is a significant opportunity.  Usually, when replacing siding we open the wall and have an opportunity to inspect the existing insulation.  It is common that we find significant voids and even completely missing insulation. This is the time to fix the issue making the home more comfortable and energy efficient.

Often clients will choose to go even further in improving the insulation in their home by adding a continuous layer of high-density foam insulation sheathing.  The value in this step is less about the amount of insulation that is added and more about where it is added.  A typical 2X4 wall has R-13 insulation in it, but the R value passing through the frame of the house is only about 5. This is known as thermal bridging and accounts for a significant amount of a homes energy loss.  By adding just ½” of foam sheathing a considerable energy savings can be realized.

5 – Dampness in the house

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As we have seen, improperly sealing the envelope of a home can lead to energy consuming air leaks.  In our hot, humid climate outside air most often carries with it a good deal of moisture.  Consequently, this moisture makes achieving comfort in the home more difficult and energy consuming.  It can cause mold, which presents significant health issues.  By tightening up your home when new siding is installed, we are able to reduce the amount of moisture that gets into the house.  If your house frequently feels damp, it could be a sign that you may need to replace your siding.

6 – Bad siding

There are a few good siding choices for our hot, humid climate.  There are far more bad ones. 

For a Free Siding Consultation you can call us at 979-696-0524 or arrange to have us call you.