The purpose of this article is twofold. First, at InterNACHI, we’d like you to take measures to keep your garage free from fire. Fortunately, there are ways this can be done, some of which are described below. Secondly, garage fires do happen, and we’d like you to make sure that a fire cannot not easily spread to the rest of your house. While you can perform many of the recommendations in this article yourself, it is a good idea to hire an InterNACHI inspector to make sure your home is safe from a garage fire.
 Why do many garages pose a fire hazard?

• Where are you most likely to do any welding, or any work on your car? These activities require working with all sorts of flammable materials. 
• Water heaters and boilers are usually stored in garages, and they can create sparks that may ignite fumes or fluids. Car batteries, too, will spark under certain conditions. 
• Oil and gasoline can drip from cars. These fluids may collect unnoticed and eventually ignite, given the proper conditions. 
• Flammable liquids, such as gasoline, motor oil and paint are commonly stored in garages. Some other examples are brake fluid, varnish, paint thinner and lighter fluid.

The following tips can help prevent garage fires and their spread:

• If the garage allows access to the attic, make sure a hatch covers this access. 
• The walls and ceiling should be fire-rated. Unfortunately, it will be difficult for untrained homeowners to tell if their walls are Type X fire-rated gypsum. An InterNACHI inspector can examine the walls and ceiling to make sure they are adequate fire barriers.  
• The floor should be clear of clutter. Loose papers, matches, oily rags, and other potentially  flammable items are extremely dangerous if they are strewn about the garage floor. 
• Use light bulbs with the proper wattage, and do not overload electrical outlets. 
• Tape down all cords and wires so they are not twisted or accidentally yanked. 

If there is a door that connects the garage to the living area, consider the following:

• Do not install a pet door in the door! Flames can more easily spread into the living area through a pet door, especially if it’s made of plastic. 
• Does the door have a window? An InterNACHI inspector can inspect the window to tell if it's fire-rated. 
• The door should be self-closing. While it may be inconvenient, especially while carrying groceries into the house from the car, doors should be self-closing. You never know when a fire will happen, and it would be unfortunate to accidentally leave the door open while a fire is starting in the garage. 
• Check the joints and open spaces around the door. Are they tightly sealed? Any openings at all can allow dangerous fumes, such as carbon monoxide or gasoline vapor, to enter the living area. An InterNACHI inspector can recommend ways to seal the door so that fumes cannot enter the living area.

Concerning items placed on the floor, you should check for the following:

• Store your flammable liquids in clearly labeled, self-closing containers, and only in small amounts. Keep them away from heaters, appliances, pilot lights and other sources of heat or flame. 
• Never store propane tanks indoors. If they catch fire, they can explode. Propane tanks are sturdy enough to be stored outdoors.
  

In summary, there are plenty of things that you can do to prevent garage fires from spreading to the rest of the house, or to keep them from starting in the first place. However, it is highly recommended that you have your garage periodically examined by an InterNACHI inspector.

​An attached garage is a garage that is physically attached to a house. Fires that begin in attached garages are more likely to spread to living areas than fires that originate in detached garages. For this reason, combined with the multitude of flammable materials commonly found in garages, attached garages should be adequately sealed from living areas. A properly sealed attached garage will ideally restrict the potential spread of fire long enough to allow the occupants time to escape the home or building.
Why are garages (both attached and detached) fire hazards?

• Oil or gasoline can drip from cars. These fluids may collect unnoticed and eventually ignite. 
• Flammable liquids, such as gasoline, oil and paint, are commonly stored in garages. Some other examples are brake fluid, degreaser, motor oil, varnish, lighter fluid, and fluids containing solvents, such as paint thinner. These chemicals are flammable in their fluid form, and some may create explosive vapors. 
• Heaters and boilers, which are frequently installed in garages, create sparks that can ignite fumes or fluids. Car batteries, too, will spark under certain conditions. 
• Mechanical or electrical building projects are often undertaken in the garage. Fires can easily start while a careless occupant is welding near flammable materials. 

Doors
The 2006 edition of the International Residential Code (IRC) states the following concerning doors that separate garages from living areas:
R309.1 Opening Penetration

Openings from a private garage directly into a room used for sleeping purposes shall not be permitted. Other openings between the garage and the residence shall be equipped with solid wood doors not less than 1-3/8” (35 mm) in thickness, solid- or honeycomb-core steel doors not less than 1-3/8” (35 mm) thick, or 20-minute fire-rated doors.
In addition, InterNACHI inspectors can check for the following while inspecting doors that separate garages from living areas:

• While not required by the IRC, it is helpful if there is at least one step leading up to the door from the garage. Gasoline fumes and other explosive gases are heavier than air, and they will accumulate at ground level. Their entry beneath a door will be slowed by an elevation increase. 
• Doors should have tight seals around their joints to prevent seepage of fumes into the living areas of the house. Carbon monoxide, with the same approximate density as air (and often warmer than surrounding air), will easily rise above the base of an elevated door and leak through unsealed joints. 
• Doors should be self-closing. Many homeowners find these doors inconvenient, but they are safer than doors that can be left ajar. While this requirement is no longer listed in the IRC, it is still a valuable recommendation. 
• If doors have windows, the glass should be fire-rated. 
• Pet doors should not be installed in fire-rated doors. Pet doors will violate the integrity of a fire barrier. 

Walls and Ceilings
The 2006 edition of the IRC states the following concerning garage walls and ceilings:
          R309.2 Separation Required
The garage shall be separated from the residence and its attic area by not less than 1/2-inch (12.7 mm) gypsum board applied to the garage side. Garages beneath habitable rooms shall be separated from all habitable rooms above by not less than 5/8-inch (15.9 mm) Type X gypsum board or equivalent. Where the separation is a floor-ceiling assembly, the structure supporting the separation shall also be protected by not less than 1/2-inch (12.7 mm) gypsum board or equivalent. Garages located less than 3 feet (914 mm) from a dwelling unit on the same lot shall be protected with not less than 1/2–inch (12.7 mm) gypsum board applied to the interior side of exterior walls that are within this area. Openings in these walls shall be regulated by Section 309.1. This provision does not apply to garage walls that are perpendicular to the adjacent dwelling unit wall.In addition, inspectors can check for the following while inspecting walls and ceilings:

• In garages that have access to the attic, a hatch cover made from an approved, fire-rated material should protect this access at all times. Missing or opened covers should be called out, as should covers made from flammable materials, such as thin plywood. Garage attic door must be constructed such that the 45-minute rating is maintained; any drywall edges on both the hatch and the surrounding area exposed to physical damage should be protected. The cover or door should be installed so that it is permanent (non-removable), with latching hardware to maintain it in a closed position. This could be accomplished by the use of spring-loaded hinges, a door closer, or hardware that will not allow it to be left in an open position when not in use. A single bolt-type or hook-and-eye hardware does not provide a positive closure, since these would allow the door to be left open. Likewise, drywall screws are fasteners--not hardware--so they cannot be used as the only means of keeping access doors closed.
• The living space should be separated from the garage by a firewall that extends from the floor to the roof. If the ceiling material is fire-rated, the firewall can terminate at the ceiling.
• Drywall joints shall be taped or sealed. Joints shall be fitted so that the gap is no more than 1/20-inch, with joints backed by either solid wood or another layer of drywall such that the joints are staggered. 

Ducts

The 2006 edition of the IRC states the following concerning ducts that penetrate garage walls and ceilings:
R309.1.1 Duct Penetration

Ducts in the garage and ducts penetrating the walls or ceilings separating the dwelling from the garage shall be constructed of a minimum No. 26-gauge (0.48 mm) steel sheet or other approved material, and shall have no openings in the garage.Dryer exhaust ducts that penetrate garage walls are serious fire hazards. These ducts are generally made from plastic and will easily melt during a fire, creating a large breach in the firewall.

Floors

The 2006 edition of the IRC states the following concerning floors in garages:
          R309.3 Floor Surface
Garage floor surfaces shall be of approved, non-combustible material. The area of the floor used for parking of automobiles or other vehicles shall be sloped to facilitate the movement of liquids to a drain or toward the main vehicle entry doorway.Inspectors should also check for the following:

• A curb should be present along the perimeter of the garage floor. This curb should be designed to prevent fluids from entering the living areas of the house. Curbs are often useful barriers for melted snow carried into the garage by automobiles, but curbs can also keep chemical spills contained in the garage. 
• Water heaters should be elevated above the floor by at least 18 inches. A pilot light may ignite spilled fluid or floor-level flammable fumes if the water heater is placed at floor level.

Concerning items placed on the floor, inspectors should check for the following:

• All flammable liquids should be stored in clearly labeled, self-closing containers, and in small amounts. They should be stored away from heaters, appliances, pilot lights, and other sources of heat and flame. 
• Propane tanks should never be stored indoors. If they catch fire, a serious explosion may result. Propane tanks are sturdy enough to be stored outdoors. 
• The floor should be clear of clutter. Loose papers, matches, oily rags, and other flammable items are dangerous if they are strewn about the garage floor.

General safety tips that inspectors can pass onto their clients:

• Use light bulbs with the proper wattage. 
• Do not overload electrical outlets. 
• Tape down all cords and wires so that they are not twisted or accidentally yanked.

In summary, attached garages should be sealed off from the living space so that fire may be contained.

Asbestos cement is a composite material consisting of Portland cement reinforced with asbestos fibers.  When manufacturers figured out ways to produce siding made using asbestos cement, it became very popular for a number of years before being banned in the U.S. in the 1970s.  InterNACHI inspectors are likely to come across this form of exterior cladding during inspections.  Inspectors and homeowners alike can benefit from knowing more about how the known health risks of asbestos apply to asbestos cement siding, too, as well as some of the common problems and issues associated with the material’s damage and deterioration.
 History 
Asbestos cement first came into use as an exterior cladding after 1907, when Austrian engineer Ludwid Hatschek came up with a way to shape the material into sheets, allowing it to be manufactured as siding and shingles.  By the 1920s, the National Board of Fire Underwriters recommended that asbestos cement replace wood as siding and roofing material because of its superior fire-resistant properties.  This recommendation from a nationally known insurance board contributed to a boost in sales and, by the 1940s, hundreds of thousands of homes in the U.S. had been constructed using asbestos cement siding.
During the late 1960s and early ‘70s, however, the news media began to report on the health hazards associated with asbestos.  As reports increased, concern grew, so the federal government took action and, in 1973, the EPA banned the use of asbestos in the manufacture of building products.
Health Risks Associated with Asbestos Cement
Asbestos fibers are a proven health hazard if inhaled.  Asbestos dust is a known cause of a type of lung cancer called asbestosis.  Mesothelioma, another deadly form of cancer that attacks internal organs, can also be caused by exposure to asbestos.  However, asbestos cement siding that has been properly installed and is not in a state of decay presents no health risks as long as it remains undisturbed.  This is because the cement binds the asbestos fibers and prevents their release into the air, under normal use and maintenance.  
The EPA deems asbestos to be hazardous when it is in a friable state, meaning that it can be crumbled, crushed or pulverized by hand pressure.  Crushed asbestos in a powdery form can allow its particles to become airborne and inhaled, causing potential health problems.  Asbestos cement products that are not in a friable state are not considered hazardous.  The only potential danger is when the cement is disturbed in a way that causes the asbestos fibers to become airborne.  
If mechanical activities performed on the siding, such as chipping, sawing, grinding or sanding, allow particles to become airborne, then the cement is considered in a friable state and, consequently, hazardous.  Deterioration can also lead to particles becoming airborne and potentially dangerous.
Advantages

• Asbestos cement siding is highly fire-resistant and will not burn or melt the way vinyl and wood siding will. 
• It resists termite damage. 
• It resists rotting. 
• It has been manufactured with textures intended to simulate the look of other cladding materials, such as wood grain. 
• It is fairly easy to clean and maintain. 
• Unlike more porous siding materials, such as wood clapboard, asbestos cement siding will not quickly soak up paint, which allows it to be painted more easily.

Disadvantages

• Asbestos cement siding is very brittle and can be easily chipped, cracked or broken.    
• The use of a pressure washer for maintenance can crack the siding and lead to moisture intrusion, if the pressure setting is high enough. 
• Asbestos cement can be dangerous if pulverized by sawing, sanding, breaking, etc. 
• It is difficult to find replacement siding for repairs. 
• This product cannot be refurbished, unlike other forms of siding.  Wood clapboard, for example, can be sanded and re-painted, and cedar shake siding can be sand-blasted and re-stained.  Either of these methods can restore wood close to its original state.  But this is not possible with asbestos cement siding. 
• It is no longer considered aesthetically desirable.

Maintenance
Damage and deterioration can lead to structural and health issues, so proper maintenance of asbestos cement building materials is a primary concern.  Keeping the siding clean and performing any minor repairs as soon as they become necessary are both important.  
Asbestos cement siding is fairly brittle and has little resistance to cracking, chipping and damage from impact, which can cause asbestos particles to become airborne.  Damage to the siding can also lead to other damage related to moisture intrusion.  Damaged areas that cannot be fixed can be replaced with non-asbestos fiber cement by a professional.  Specific fiber cement materials have been manufactured for repairs that are intended to mimic the look of asbestos cement siding.  
Landscaping features, such as a row of shrubs, can be incorporated around the home to help protect the siding from impact damage. 
Inspection Tips
Here are some common problems associated with asbestos cement siding that inspectors are likely to encounter:

• Chipping and cracking often occur with this brittle material. 
• Fasteners used to hold the siding in place may deteriorate at a faster rate than the siding. 
• Discoloration and staining may occur from corrosion or runoff from an adjacent material.  The discoloration may be normal, but it could also indicate a chemical reaction that has decreased the durability of the material. 
• Like many other cement products, efflorescence may appear on asbestos cement siding.  This crystalline growth can indicate that water is passing through the material, promoting deterioration of the cement. 
• Biological growth, such as moss and algae, can occur if conditions are favorable.  This growth may stimulate surface deterioration and staining.

Because it was such a popular cladding material for many years, inspectors are likely to encounter asbestos cement siding when inspecting exteriors.  Knowing some of the health risks associated with this material can be useful when answering clients’ questions about asbestos, although any specific concerns should be deferred to the appropriate healthcare professional.  Homeowners will want to hire an InterNACHI inspector for the periodic inspection of this type of cladding as part of their annual or regular home maintenance.