InterNACHI » "The Inspectors Journal®"

New article: What is a green home inspection?

April 13th, 2010

This ever-growing area of home inspections is poised to explode with opportunity.  Green building continues to gain in popularity as many new home builders and buyers strive to live more sustainably, and even off the grid.  Re-visit the fundamentals in this article titled “What is a Green Home Inspection?”

This blog entry was posted by Nick Gromicko.

Is the U.S. facing a water crisis?

April 12th, 2010

Inspectors who deal with wells and rural properties should be aware that the U.S. groundwater and aquifer systems are being threatened by depletion.  Read “The Potential for a Water Crisis” now.

This blog entry was posted by Nick Gromicko.

New article on ghosting

April 9th, 2010

What is ghosting?  Click here to read about the discoloring effects of ghosting on surfaces in the home.

This blog entry was posted by Nick Gromicko.

New article on inspecting EPDM

April 9th, 2010

Many low-slope roofs use EPDM coverings.  Click here to read “Inspecting EPDM.”

This blog entry was posted by Nick Gromicko.

New article on inspecting historic homes

April 9th, 2010

What exactly is a “historic” home?  Is it just an older house, or is it something very different from the average home?  Click here to read “Inspecting Historic Homes” so that you know what to look for.

This blog entry was posted by Nick Gromicko.

New article on inspectors as expert witnesses

April 9th, 2010

Are you an inspector who wants to expand his business by giving testimony in court cases as an expert witness?  Put your expertise to use and get paid for it.  Click here to read “Inspectors as Expert Witnesses.”

This blog entry was posted by Nick Gromicko.

New article on detecting corrosion in concrete-encased steel

April 9th, 2010

How can inspectors tell if steel encased in concrete, such as rebar, is corroding?  Click here to read “Detecting Corrosion in Concrete-Encased Steel.”

This blog entry was posted by Nick Gromicko.

Bump Keys and What Inspectors Should Know About Them

April 9th, 2010

Bumps keys are used to access pin-tumbler locks using keys other than the ones originally produced for the lock.  Inspectors should know how they work, and should inform their clients that they may need to upgrade their exterior door locks for added security.  Click  here to read “Bump Keys and What Inspectors Should Know About Them.”

This blog entry was posted by Nick Gromicko.

Three types of underlayment used beneath roofing materials:

March 21st, 2010

There are three basic types of underlayment used beneath roofing materials:

  • asphalt-saturated felt;
  • rubberized asphalt; and
  • non-bitumen synthetic.

Find out more by reading this article: Roofing Underlayment Types.

This blog entry was posted by Nick Gromicko.

Inspecting Underlayment on Roofs.

March 21st, 2010

All home inspectors should understand the basic properties and general installation requirements of roofing underlayment.  Find out more by reading our new article on Inspecting Underlayment.

This blog entry was posted by Nick Gromicko.

Nick Gromicko with Governor Charlie Crist.

February 15th, 2010

InterNACHI Founder Nick Gromicko and Governor Charlie Crist.

This blog entry was posted by Nick Gromicko.

Frost Proof Hose Bibs

February 14th, 2010

I live in Colorado Springs and perform Home and Commercial inspections along the Front Range.  In one of my home inspections I walked into a basement bedroom and was struck by a particular odor. It was that musty moldy odor one dreads,  after further investigation I discovered a “frost proof” hose bib located in the ceiling along a back wall had not been so “frost proof”.  In the photo below the split that is visible is due to a failed valve.

Note the length of this valve which is 18” long, the actual shut off is at the back of the valve which leaves 18” of pipe without water in it which is sufficient for winter conditions.  This valve however had failed leaving water in the pipe and subject to freezing.

The owner had to remove the carpet, a section of drywall and insulation, mitigate the mold in the wall cavity and have these items replaced.

The question remains, is your “frost proof” hose bibs operating correctly?
One good check is to operate your hose bib, when shut off a small amount of water should drain out. This would be the water in the 18” of pipe, because remember the valve is in the back of the unit.

Even in the middle of winter we can have 60 degree weather which is a good time to water trees or wash your vehicle, don’t forget to disconnect the hose from your hose bib or you will be inviting disaster.

I hope this helps to prevent a catastrophe around your home or business.

failed frost proof hose bib close up of split from freezing

This blog entry was posted by Tom Camp.

Roof and Ceiling Leak Detection

February 11th, 2010

An infrared inspection of your roof can detect eveidence of latent moisture within your roof cavities and it can determine the potential for ice dams, plugged drains, and water retention that may cause roof damage and/or leakage which could lead to serious damage to your living area if not detected on-time. Roofing materials are very expensive to replace and the repairs can cost you roughly $20.00 or more a square foot. My infrared roof evaluation you can save you a bundle (in the long run) by knowing if certain roof sections need minor repair now to avoid major repair or replacement later, or to simply determine if the whole entire roof needs to be replaced in the not-so-distant future. Thermal imaging can give you the existing roof information in a nice neat visual package.

This EPDM roof looks great visually, but a major moisture build-up (under the rubber membrane) was easily detected utilizing my infrared camera.

During a home inspection, roof leaks are typically discovered by my direct observations and then confirmed by utilizing moisture meters on the sheathing below. But if I detect a moist area and the roof sheathing is not visible from below (such as a finished cathedral ceiling or a ceiling below a living area) the exact area of the leak can not be determined. Most homeowners have the misconception that moisture stains are caused from leaks that are directly above a wet area. It’s just not true in most situations. On gable roofs, some leaks occur at the ridge line area and cling to the rafters for quite a distance until it finally drips onto the ceiling below. In order for anyone to locate the exact area of the leak, the damaged ceiling must first be removed. This removal is necessary in order to “visualize” the exact intrusion point at the underside of the roof sheathing. Now before any of the ceilings can be removed, all the furniture must be removed from below the affected area. Then the floor must be protected from the falling debris and possibly requiring a scaffold system. All of this can cost hundreds and even thousands of dollars! Infrared Thermography is an invaluable non-destructive and non-contact tool that can detect and pinpoint hidden roof leaks without even damaging the interior or exterior surfaces. Then once I pinpoint the problem area, minimum surface areas can be removed in order to make the necessary repairs.

I prefer to perform all exterior flat roof inspections in the early evening hours. In order to perform the infrared inspection correctly, I require solar heating of a hot sunny day to heat up the roof surface. Then in the early evening (after the sun goes down), the roof starts to cool allowing my infrared camera to be able to detect obvious thermal differences (anomalies) if there are any moisture intrusions within the roof surface. Thermal properties of water are very unique (high thermal capacity), allowing water to be thermally observed on the surface and on the underside of roofing materials. If water is actively seeping into the cavity of a roof surface, the dry roof insulation will cool much faster than the soggy wet roof insulation, making it possible for me to observe the thermal differences.

My infrared roof inspections have proven to be a beneficial option for testing sub-surface roof areas that can not be seen visually. Regularly scheduled infrared roof inspections will allow you to find moisture damage and water leaks that have not yet become apparent. This is the most cost-effective approach to any roof maintenance. I have the knowledge and experience to correctly acquire and interpret roof infrared inspection data to you and then provide you with a professional easy-to-understand infrared roof report within hours of your inspection.

Visually, this roof structure looks good, but infrared imaging detects anomalies immediately.

The source of this roof leak was unable to be located visually, but my infrared camera detected the exact source of the leak immediately.

Don’t wait until it’s too late. Infrared imaging will detect concealed issues.

See more information regarding INFRARED and THERMAL IMAGING on my website at

This blog entry was posted by David Valley.

Heat Movement

February 11th, 2010

Heat, energy and insulation are all related to each other. As inspectors we should understand how heat moves around inside a home, and how insulation can control that movement. One main reason to understand how heat moves is because warm air can carry moisture, and warm moist air needs to be controlled in relation to a building envelope. Uncontrolled, moving warm air and moisture can cause lots of problems. Another reason to learn about heat is that insulation provides a resistance to the flow of heat, and the more insulation there is, the less energy is needed to heat and cool the house.

Heat needs to be controlled to keep the occupants of the home comfortable. When a home is well insulated, your client will save on energy costs. After learning the information in the next few sections about heat, moisture, air, and insulation, you’ll be able to perform a great inspection, and speak to your client about how the building envelope is functioning.

Now, let’s talk heat. There are essentially three ways that heat moves from one area to another. When bodies of unequal temperatures are near each other, heat leaves one body and goes to the other. Heat moves from the hotter body, and the colder body absorbs it. The greater the difference in temperature, the greater the rate of flow of the heat.

Heat moves from one body to another by the following ways:

· Radiation;

· Conduction; and

· Convection.


Radiation is the transfer of heat energy by electromagnetic wave motion. Heat is transferred in direct rays. It travels in a straight line from the source to the body. The closer you are to the hot object, the warmer you feel. The intensity of the heat radiated from the object decreases as the distance from the object increases.

You feel cool in a room that has a cold floor, walls and ceiling. The amount of heat loss from your body in that room depends upon the relative temperature of the objects in that room. The colder the floor is (relative to the temperature of your feet), the great the heat loss from your body will be standing there. If the floor, walls and ceiling of that room are relatively warmer than your body temperature, then heat will be radiated to your body from those objects or surfaces.

When you step into a cold room, you can immediately feel the heat energy leaving your body. Use all of your senses as an inspector when moving about the house. Just entering a space with your body can tell you a lot of information about that space, the insulation, the heat, air movement, and even moisture or humidity levels. Some inspectors can give a good estimate on the temperature of an attic space simply by entering it. Keep aware of your surroundings when moving about the interior of the house.

Radiant heat emits in all directions. Radiant heating in residential buildings include piping and electrical wiring in floors, walls and ceilings. Reflective materials are commonly used in a radiant heat emitting system in order to direct or control where the heat is emitted.

Radiation happens when heat moves as energy waves, called infrared waves, directly from its source to something else. This is how the heat from the Sun gets to Earth. In fact, all hot things radiate heat to cooler things. When the heat waves hit the cooler thing, they make the molecules of the cooler object speed up. When the molecules of that object speed up, the object becomes hotter.


Conduction is the transfer of heat from one molecule to another, or through one substance to another. It is heat that moves from one body to another by direct contact. For example, heat is transferred by conduction from a boiler heat exchanger to the water passing through it. When you touch a suction lines of an air conditioner and it feels warm, that’s heat energy moving from the warm copper pipe to your cooler hand – by conduction.

Heat is a form of energy, and when that heat comes into contact with matter, it makes the atoms and molecules move. When atoms or molecules move, they collide with other atoms or molecules and make them move too. This movement transfers heat through matter.

This is demonstrated when touching a ceramic coffee cup. The exterior surface of the cup is warm to the touch because the heat of the hot coffee transferred through the cup material.


Convection is known by most people by the using the phrase “Heat rises.” Convection is the transfer of heat by warming the air next to a hot surface and then moving that warm air. It’s the transfer of heat by the motion of the heated matter itself. The air moves from one place to another, carrying heat along with it. Since warm air is lighter than the cool air around it, the warm air (or heat) rises.

Warm fluids tend to rise while the surrounding cool fluids fall. This rising and falling tends to form loops or convective loops, where warm air, for example rises and cool air falls. Early warm-air furnaces, gravity furnaces, used principles of convective loops. In a gravity system the warm air rises and cool air falls, and this is how the gravity warm-air heating system circulated air.

When a certain amount of air is heated up, it expands and takes up more space.  In other words, hot air is less dense than cold air.  Any substance that is less dense than the fluid (gas or liquid) of its surroundings will float.  Hot air floats on cold air because it is less dense, just as a piece of wood floats because it is less dense than water.  Warm air is often described as weighing less than cool air. Warm air rises, and cool air falls. The weight per unit volume of air decreases as its temperature increases. And conversely, the weight per unit volume of air increases as its temperature decreases.

Inside a wall cavity, there can be convective loops, where cool and warm air are moving about inside the wall cavity. If warm, moist air comes in contact with a cold surface of that wall assembly, then condensation may form inside the wall. And that’s not good.

For another example, an old gravity furnace heats the air; the air gets lighter and rises out of the heating system. Cool air enters the heating system and pushes or displaces the warm, rising air. The warm air rises up through warm-air ducts or pipes (often called stacks) that are inside the walls. The warm air rises up through the building. The warm air enters a room through the supply registers on the wall or floor. The cool air falls out of the room and might return through a return grille, and travel back through return ducts to the heating system.

Some houses with old gravity heating systems may not have a lot of ducts and pipes, but might rely on large openings (covered with iron grates or grilles) in the floors that allow the cool air to fall down through the building. The cool air is allowed to simply fall back to the furnace – hence the name gravity warm-air heating system.

The air circulation in a house with a gravity warm-air heating system will depend upon the temperature difference between the warm air rising and the cool air falling. The greater the difference, the greater the speed of the air circulating.


So, heat moves from one body to another by the following three ways:

· Radiation;

· Conduction; and

· Convection.

Understanding how heat moves will help you understand how moisture moves too.  You can find information about how to inspect for moisture and other subjects at

This blog entry was posted by Ben Gromicko.

Nevada Real Estate Division approves InterNACHI’s free, online home inspection courses.

February 10th, 2010

InterNACHI is pleased to announce that the State of Nevada, Department of Business and Industry, Real Estate Division approved InterNACHI’s free, online courses for home inspector continuing education purposes.

The free, online inspection courses include such topics as: commercial property inspections, structural issues, roofing inspections, plumbing inspections, log home inspections, green building, electrical inspections, safety practices for home inspectors, means of egress, and thermal imaging.

The Nevada Department of Agriculture also approved InterNACHI’s free, online Wood Destroying Organism course.

InterNACHI is the largest inspection school in Nevada and the world and has been awarded hundreds of government approvals and accreditations.

CLICK HERE to see actual home inspection continuing education approval certificates from Nevada.

This blog entry was posted by Nick Gromicko.

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