Beware How You Finish Your Moisture and Mold Resistant Drywall

CTG_FibaTape_Mold-X10_Details_ImageWhy are you spending all your effort and resources on moisture and mold resistant drywall and then finishing it with a standard, drywall paper tape? 

That is what often happens. In high moisture areas such as bathrooms and kitchens you need to make sure that you do not erode the added value of the drywall by finishing with standard tapes. There are fiberglass mesh drywall tapes that provide the best defense against mold and moisture when used with mold-resistant treated paper and paperless drywall. 

As I have pointed out before, you want to remove the presence of food which is one the four legs needed for mold to grow:  right temperature, oxygen, moisture and food – in this case – the paper drywall tape.

Always keep in mind that everything is a system and you need to consider all aspects of the wall assembly and how you want it to perform or you may not get the outcome you were striving for.

Don’t Stop at the Surface with Moisture and Mold Damage

1316551358_254450912_4-Residential-and-commercial-Flood-Water-Damage-services-free-est-8888110187-ServicesMold Awareness Month Tip #2: When you see signs of moisture damage either on the exterior or interior you can’t just address this at the surface.  You have to keep digging until you get to dry materials.  If that means tearing out the drywall and the insulation until you get to something dry, so be it. You can’t just fix the surface because it was wet. If you have to replace materials following moisture damage consider using a mold and moisture resistant drywall and a smart vapor retarder with your insulation to add protection to your wall assembly. You will be building in more robustness to an area of your home that is apparently susceptible to moisture intrusion.

That’s from the outside too.  If you find some water damage around your window and you tear it out you can’t stop there.  Take your screwdriver or awl and probe the wood behind it to find out how far the damage goes. If you don’t correct the problem at the source and replace all the damaged materials, the chances of mold occurring in this area are very good..

So, don’t stop at the surface or just treat the symptoms.  You have to exhaust the symptoms and get to the source.

Remember, if you see moisture damage whether inside or outside the building don’t stop digging and probing until you get to dry.

If It Smells Bad It Is Bad

 September is Mold Awareness Month and I thought it would be a good time to provide some helpful tips about mold.  This was prompted by a discussion that came up the other day when I was conducting a webinar on “The Future of Building Materials and Their Impact on How we Build”.  Mold is not always visible but early detection of a mold problem is critical to the health of a building.

Mold-in-basement2Mold has a long history, in fact, references about mold can be found in the Bible (Leviticus 14: 33-53). When you are dealing with living things that have that much staying power, it is clear that you can’t or won’t get rid of them easily.  In a previous blog, I discussed the four things that mold needs to grow: the right temperature, sufficient water, oxygen and food.  But you can control the growth by eliminating one of the elements. If the problem is moisture in the wall cavity you need to remove all the wet insulation and drywall and thoroughly dry the assembly.

One of the best ways to identify a mold problem early is through smell. Often you can smell it before you see it. If you smell something that doesn’t smell right, trust your instincts and check it out.  This is your learned response to protect you from dangerous materials.

If you think you may have mold, get on your hands and knees and sniff around the outlets in your walls. If you have it – you will smell it.  Also, check areas that do not have adequate ventilation (closets or other spaces with no vents or registers).

If you smell it that means the mold spores are airborne and that is when they present the most health risk. When it’s dormant you are not going to smell it but if the spores go aerosol, you need take action.

 

If You Suspect Mold in a Building – Remember the Hindenburg!

Lucas Hamilton

If you have had some moisture damage in your building and suspect or see that you have some mold, remember The Hindenburg

Before you cut into the wall, compartmentalize and put the space under a negative pressure.  The last thing you want to do in a building when you think you may have had a moisture issue and suspect that mold could be growing behind the wall is to disturb it and have the mold spores release into the air within the building. If you think you may have a problem and need to cut into the wall take these steps to create negative pressure in the room:

  • Close the door
  • Open a window
  • Put a fan in the window blowing out to create negative pressure in the room
  • Then you can safely cut into the wall to treat the mold

The lesson we learned from the Hindenburg relates to the smoking lounge.  The lounge was kept under positive pressure and the smoke leaked out into the rest of the dirigible so that if there was a gas leak in the envelope of the dirigible, the gas could not flow into the smoking lounge to get ignited by a pipe or a lighter.

You are doing the same thing here but in reverse.  You are putting the space into a negative pressure before you disturb the space so that contaminants could not possibly flow into the building.

Lucas Hamilton is Manager, Building Science Applications for CertainTeed Corporation

It is Spring Tune-Up Time for Your Home

Lucas Hamilton

Lucas Hamilton is Manager, Building Science Applications for CertainTeed Corporation

It is spring and we just celebrated the 42nd Anniversary of Earth Day. While you are contemplating changes you can make to your home and property to conserve energy or improve curb appeal in a re-heating real estate market, keep in mind that this is the perfect time to do a home inspection and make sure that your home is efficient, safe and in-keeping with the Earth Day ideals.

Here are a few places you should inspect:

  • Inspect your roof for missing or broken shingles or possible places where water could come in. If your roof is not ventilated properly you could have damage from ice dams. Nothing could be greener than making our existing resources last longer and your roof is the first line of defense.
  • Check your attic or crawl space to make sure that water is not coming in.  It is also a good time to see if you need to add additional insulation to your attic space. The attic is one of the easiest places in a home to add insulation and insulation prices are about as low as they get right now so no point in waiting.
  • Clean your gutters.  Make sure they are cleared for the rainy season. Leaves and dirt can build up in any season. Clogged gutters are one of the most efficient ways to redirect water back into your building once you have already shed it.
  • Tune up your air conditioner.  It is the prime time for specials from contractors. Making sure that your unit is working properly can help save on utility bills and actually improve your indoor air quality.
  • Check your walls and foundation for any cracks that could cause moisture infiltration. You must maintain your barriers.
  • Check the basement for mold. When the temperature gets above 41 degrees that is when mold is happy. If mold is present you will be able to smell it. If it smells bad it is bad.

If you have an older home it is critical to make upgrades and improvements when signs of weakness appear.  Taking care of simple repairs will save you money over time but will also make your home more competitive in the marketplace and make for a healthier habitat for you and your family.

It’s Not Just Wallboard Anymore

 

Ashwin Himat

Ashwin Himat

Ashwin Himat is Director of Marketing – North America for CertainTeed Gypsum

New innovations in technology are redefining building products industry-wide. Manufacturers are improving products today based on solutions to environmental concerns and to address indoor environmental quality. Wallboard is no exception.

Historically, wallboard enabled residential and commercial construction to provide better fire protection and a flat, smooth surface that could be easily painted or wallpapered. Because of the recycled content of wallboard, it has always been considered a sustainable product but its function rather than its features were the primary selling point.

The drivers for innovation of wallboard products predominately came from the commercial build community. Earlier innovations in wallboard provided moisture resistance for areas of buildings with high moisture such as bathrooms and kitchens. With increased concerns and claims regarding mold in buildings, a technology was developed to provide mold and moisture resistance to wallboard.  Mold is a potentially serious health issue for people so the ability to include a mold resistant wallboard in a home or building susceptible to mold reduces the potential.

With the rapidly growing awareness of the importance of indoor air quality and its impact on health and productivity, recent technology innovations have led to the introduction of wallboards that clean the air.  By removing volatile organic compounds (VOC’s) such as formaldehyde and other aldehydes from the air and converting them into safe, inert compounds, these wallboards can improve indoor air quality for generations. 

In response to the growing marketplace demand for acoustic comfort, manufacturers have increased innovations in the area of noise-reducing gypsum board, specifically designed for wall systems requiring high STC ratings where acoustic management is needed.

The commercial build community is aware of these advancements in wallboard and they are including them in specifications especially in the educational and healthcare arena. But these wallboards adapt well to residential construction as well especially when designing custom homes that may include home theaters or music rooms.

Homeowners need to be educated about the options they have when either building a new home or expanding an existing one.  Decisions made about the walls and ceilings of a home should be carefully considered because ones overall comfort depends on it.

Wallboard is not a one size fits all product any longer so when it comes to improving comfort and indoor environmental quality remember to consider the best solutions for your walls and ceilings.

Excessive Wet Weather Can Lead to Mold

Lucas Hamilton

The historic rain that the United States has endured in 2011 has increased moisture levels in places where moisture has never been a problem. I have heard from many people around the country who have never had water in their homes but have recently sustained water damage and are now concerned about potential mold.

As I have mentioned in a previous blog, mold needs four things to grow:  moisture (liquid water), food (typically starch or sugar), temperature between 41° and 104° and oxygen.  When water is trapped behind walls or paneling, the other elements will most likely be present and the potential for mold growth will exist. Try to clean and dry areas subjected to water within 48 hours to help prevent mold growth. After cleaning and drying, continue to be sensitive to musty odors in the affected area.

Check the exterior of homes and building regularly for accumulating ground water.  Many parts of the country have far exceeded saturation and mold can begin for form outside and find its way inside. If water is accumulating against your foundation, take measures to drain the water away from your building. Keeping things dry is the key to preventing mold growth.

There are many products available today to help protect the home or building from moisture infiltration and mold growth.  There are coating products that can be applied to dry materials to mitigate any mold growth potentials for that surface in the future. If materials are wet and can’t be cleaned or completely dried, remove them from the building and replace them with new materials which may be more mold resistant. Fiber glass doesn’t have the food needed for mold growth but often when insulation gets wet, the water which intruded into the cavity was dirty and brought food along with it. If you have wet insulation, replace it with new fiber glass.  If replacing drywall, consider selecting a board that that contains mold and moisture inhibitors.

Many people have sensitivities to mold and it can be a health concern.  Make sure that you take extra care to check for mold especially if this is the first time you are dealing with water inside your home or building. Use a mixture of common sense and caution- if it smells or looks bad assume that it is bad and take appropriate measures.

Lucas Hamilton is Manager, Building Science Applications for CertainTeed Corporation

Radon Mitigation Starts with Proper Home Foundations

Lucas Hamilton

The use of foundation drainage systems helps with water control, mold and moisture issues and Indoor Environmental Quality (IEQ) in a building. But, bear in mind that those same remedial efforts, if using the Form-A-Drain system, will also help with radon mitigation. In the same manner that these systems relieve head water pressure on the cold joint of the foundation / footer, they give migrating radon gas a path of least resistance away from the home.

Radon gas is a colorless, odorless, tasteless noble gas, occurring naturally as the decay product of uranium. Radon gas from natural sources can accumulate in buildings, especially in confined areas such as attics and basements.

Most regions of the U.S. encounter radon gas especially if they have basements or crawlspaces.  It is important to test for radon especially if the basement is part of the living area of the home.

Many homeowners are not aware they have a brewing radon problem until they put the house on the market.  It can, in some instances, be costly to install a radon mitigation system.

Leave in place Form-A-Drain systems pay for themselves not only in their benefits related to the forming of footings and moisture management but the added value of what they provide with regard to radon venting; making the use of Form-A- Drain product for all new construction projects the best ‘drainage’ solution for contractors, architects and builders.

Lucas Hamilton is Manager, Building Science Applications for CertainTeed Corporation

Tolerance for Moisture Intrusion is a Challenge in Vancouver

Lucas Hamilton

Earlier this week I traveled to Vancouver, British Columbia, Canada to present the workshop on Mold and Moisture Control in buildings at the final [Be Certain] event.  It has been fascinating to present these workshops in different Northern climates and creating simulations to address the specific challenges faced in these areas of North America.

Previously, I blogged about polyethylene in Calgary, Alberta, Canada and the challenges faced in controlling moisture because of the use of exterior insulation. In preparation for my Vancouver workshop, I re-ran the modeling for Vancouver and the results were very interesting.

Polyamide films, like MemBrain™ because it is a breathable vapor retarder can provide additional tolerance for moisture intrusion in many climates, but in extreme climates like Vancouver there is almost no way to survive water intrusion.

In such climates, the best course is to build into the design redundant drainage planes and flash, flash, flash. Expect water to pass your principle line of defense and stop it with a secondary line of defense which will evacuate the intruding moisture to the exterior environment. This would be like a window rough opening being completely wrapped prior to window installation and this rough opening flashing draining water out and onto the face of a water resistive barrier (WRB) which leads to an egress at the base of the wall system.

While there is so much we know about moisture management, there is always more to learn and our thinking must be comprehensive. If we don’t learn from the past, our attempts to build air-tight and moisture-tight buildings will leave us looking more like Wile E. Coyote grasping for the next solution. I am not comfortable with that. Thoughts?

Lucas Hamilton is Manager, Building Science Applications for CertainTeed Corporation

Is Polyethylene Creating Potential for Mold?

Lucas Hamilton

Last week, I was in Calgary, Alberta, Canada for one of CertainTeed’s Be Certain events conducting training sessions on designing for Mold and Moisture control in buildings.  In preparation for the sessions, I ran computer simulations on typical construction models in Calgary.  This gave me a better awareness of how they build as well as scientific understanding of construction practices in the province.

In extremely cold and dry climates like Calgary, which is similar to Colorado, use of exterior insulations is very common.  This practice emphasizes the use of insulation on the outside of the building.  This cuts down the thermal connectivity of the building frame to make the building more energy efficient.

The 2009 International Energy Conservation Code (IECC) mandates the use of exterior insulation in cold climates. However, when you do this with traditional materials such as rigid foam plastics, you may reduce the potential to dry a building to the outside.  If a wall gets wet normally, dry air on the outside can act as a reservoir to dry the building. When insulations like extruded polystyrenes are used on the outside of the building, while being extremely energy efficient, they may reduce this drying potential.

Some new computer modeling tools have the ability to create window leaks and other scenarios that could occur from construction defects that would place water into the wall.  In the Calgary scenarios I ran, if a window leaks and the water is not drained to the exterior surface of the water resistive barrier, it becomes trapped between two non-breathing layers – the exterior insulation and the interior traditional vapor retarder polyethylene (which they still use in Alberta.)  The wall can not dry and this creates the risk of growing mold. 

Building scientists and manufacturers have been preaching eliminating polyethylene from our buildings here in the U.S. for quite awhile, and promoting the use of smart vapor retarders as a solution to the problem.

As construction practices change to keep more energy in the building, some of the measures taken may unfortunately alter the traditional moisture balance of the assemblies and actually reduce our tolerance of intruding moisture. We must be very mindful of this as we continue to tighten our buildings while striving for improved indoor environmental quality.

We conclude our Be Certain events in Toronto and Vancouver later this month.  Stay tuned for how mold and moisture affect the building envelope in Ontario and British Columbia.

Lucas Hamilton is Manager, Building Science Applications for CertainTeed Corporation