When a certified technician inspects and cleans a dryer vent, they also verify that the correct type of duct is in use. For example, plastic transition ducts (joining the dyer to the wall) should be replaced with metal duct, because it is non-flammable, unlike plastic.

Annual dryer exhaust vent inspections (also known as dryer exhaust duct inspections) are more necessary than ever before due to the complex construction of homes built today. Newer homes tend to have dryers located away from an outside wall in bathrooms, kitchens and in hall closets which is convenient, but potentially dangerous from a safety standpoint. These new locations mean that dryers tend to be vented longer distances and vents are generally installed with more bends to accommodate the extended path they must take through the home. As a result, dryer ducts are harder to access and this additional length creates more places where lint can collect and animals and birds can hide.

The Chimney Safety Institute of America recommends that CSIA Certified Dryer Exhaust Technicians® (C-DET) perform dryer vent inspections on an annual basis to ensure efficient operation of your clothes dryer system. Certified Dryer Exhaust Technicians have passed an extensive exam on the proper inspection and maintenance of dryer vents, including applicable codes and standards relating to these systems.

In addition to these safety considerations, annual clothes dryer exhaust inspections by a CSIA Certified Dryer Exhaust Technician® can also increase the efficiency of your clothes dryer and decrease the wear on your appliance:

Appliance Efficiency
A clean exhaust duct prevents heat, moisture and, in the case of gas clothes dryers, carbon monoxide from being trapped in your home. When this type of spillage occurs, energy, natural resources and time are all wasted because your appliance works too hard and runs longer than necessary.

Wear on Your Clothes Dryer
If your dryer takes twice as long to dry clothes as it should, the number of loads that it will dry in its lifetime is cut in half. When the dryer runs at higher than designed temperatures, the life of your clothes dryer decreases even more. This can lead to the heating element burning out or a fire could ignite as a result of overworked safety controls.

Masonry Chimneys
A masonry chimney is constructed of a variety of masonry and metal materials, including brick, mortar, concrete, concrete block, stone, flue tile, steel and cast iron. All masonry chimneys contain combinations of, or possibly all of, these materials, most of which are adversely affected by direct contact with water or water penetration.

Water Penetration
All masonry chimney construction materials, except stone, will suffer accelerated deterioration as a result of prolonged contact with water. Masonry materials deteriorate quickly when exposed to the freeze/thaw process, in which moisture that has penetrated the materials periodically freezes and expands causing undue stress. Water in the chimney also causes rust in steel and cast iron, weakening or destroying the metal parts.

Note: While most stone is not affected by water penetration, large amounts of mortar are required to bond the stone together properly. Therefore, a stone chimney – just like a brick chimney – should be protected from the effects of water penetration.

Water penetration can cause interior and exterior damage to your home and masonry chimney including:

 • Rusted damper assemblies

• Deteriorated metal or masonry firebox assemblies

• Rusted fireplace accessories and glass doors

• Rotting adjacent wood and ruined wall coverings

• Water stained walls and ceiling

• Clogged clean out area

• Deteriorated central heating system

• Stained chimney exterior

• Decayed exterior mortar

• Cracked or deteriorated flue lining system

• Collapsed hearth support

• Tilted or collapsed chimney structure

• Chimney settlement

In addition, when water mixes with creosote in a wood burning chimney system, it will generate a highly disagreeable odor that can permeate a home. 

Preventing Water Damage
Chimney caps, also called rain covers, are probably the most inexpensive preventive measure that a homeowner can employ to prevent water penetration and damage to the chimney. Chimney caps have long been recognized as an important chimney safety and damage prevention component. Underwriters Laboratories (UL) specifies that any chimney lining system that is to be listed to their test standard must include a chimney cap. 

Chimneys have one or more large openings (flues) at the top that can collect rainwater and funnel it directly to the chimney interior. A commonly-sized flue has the potential to allow large amounts of rain or snow into the chimney during just one winter when freeze/thaw cycles are common.

Chimney caps also provide other benefits. A strong, well-designed cap will prevent birds and animals from entering and nesting in the chimney. Caps also function as spark arrestors, preventing sparks from landing on the roof or other nearby combustible material. 

A chimney cap should be easily removable to facilitate inspection and cleaning. For a long and effective service lifetime, a cap should be constructed of sturdy, durable and corrosion resistant material. Caps may be designed to cover a single flue, multiple flues, a large portion of the chimney or the entire chimney top. A full coverage chimney cap usually represents a larger initial investment. However, it is probably the best investment for long-term protection because of its ability to protect the entire chimney crown.

Repair or Replace a Damaged Chimney Crown
The chimney crown (also referred to as the chimney wash) is the top element of a masonry chimney. It covers and seals the top of the chimney from the flue liner to the chimney edge. The crown should provide a downward slope that will direct the water from the flue to the edge of the crown. The overhanging drip edge, by directing the run-off from the crown away from the chimney, helps prevent erosion of the brick and mortar in the chimney’s vertical surfaces. 

Most masonry chimneys are built with an inadequate crown constructed from common mortar mix that is designed for years of weather abuse without cracking, chipping or deteriorating. A proper chimney crown should be constructed of a Portland cement-based mixture and cast or formed so it provides an overhang projecting beyond all sides of the chimney by a minimum of two inches. The flue liner tile should also project above the crown a minimum of two inches.

Repair Deteriorated Mortar Joints

Deteriorated mortar joints on the chimneys exterior are entry spots for water. Proper mortar joints have no gaps or missing mortar and are shaped in a way that directs water out of the joint. When mortar deteriorates from exposure to weather, it becomes much more absorbent. A common repair for deteriorated mortar joints is called repointing. In this process, the existing mortar joint is cut to an appropriate depth and the joint is repacked with new mortar. The joint is then cut to form a concave surface that will direct water out of the joint. A good repointing job, using proper materials, will give the chimney a much longer life span, and often will enhance its appearance. 

Repair or Replace Flashing
Flashing is the seal between the roofing material and the chimney. Flashing prevents rainwater or snow melt from running down the chimney into living spaces where it can damage ceilings and walls and cause rot in rafters. The flashing is the expansion joint between two dissimilar materials. It is designed to allow both the roof and the chimney to expand and contract at their own rates without breaking the waterproof seal in either area.

Install a Cricket to Stop or Prevent Leaks
If the chimney is located on the low side of the roof where water run-off is directed against the chimney, the installation of a cricket will afford additional protection against water leaking into the home. A cricket is a water deflector that serves to direct rainwater away from the chimney. Crickets are recommended on chimneys more than 30-inches wide and they are especially important on steep roofs.

Waterproof Your Chimney
Most masonry materials are porous and will absorb large amounts of water. Common brick is like a sponge, absorbing water and wicking moisture to the chimney interior. Defective mortar joints or the use of improper mortar or brick can greatly increase the tendency to absorb and convey water to the interior of the masonry chimney.

Several products have been developed specifically for use as waterproofing agents on masonry chimneys. These formulas are 100% vapor permeable, which means that they allow the chimney to breathe. Therefore, water that has penetrated and the vapors produced when the chimney dries out or the water vapors produced during use are allowed to escape, while the waterproofing agent prevents water from entering from the outside. These products usually have a five- to ten-year warranty. Paint or clear sealers should never be used as a waterproofing agent because they will trap water vapors and moisture inside the chimney causing further deterioration.

Waterproofing is a preventive measure. When damage or deterioration (gaps, voids, cracks, missing mortar, etc.) already exists in a masonry structure, the chimney should be repaired before the waterproofing agent is applied. The chimney exterior may also need to be cleaned before the waterproofing material is applied.

As in the past, masonry fireplace and chimneys are constructed onsite as the house is built. The performance of the fireplace was often dependent upon proper construction. Today, there are factory-built fireplaces, which are manufactured according to an engineered design. Proper installation, however, is still a critical factor in the safe operation of these units.

Q. What is a factory-built fireplace?

Unlike traditional site-built masonry fireplaces, most factory-built fireplaces are made of metal and may use a combination of insulated walls, glass doors, air-cooled pipe and blowers to circulate the heat produced by the fire. The factory-built fireplace and chimney are a complete system engineered to work safely and efficiently together. Both units (fireplace and chimney) undergo testing together, and are then are listed specifically for use with one another. In other words, a factory-built fireplace has a specific chimney that is appropriate for use with that specific fireplace.

Although models vary, factory-built fireplaces generally generate heat for the house in one of two ways. With the standard radiant heat method, the heat produced by the fire radiates from the fireplace into the room. This system is limited as to the amount of heat it will return to the house.  The circulating air method uses louvers and at least one blower to force air along the hot walls, picking up heat and forcing it back into the living space.

Q. How is a factory-built fireplace different from a traditional fireplace?

Because a factory-built unit is so much lighter than masonry fireplaces, these fireplaces do not require the concrete foundation necessary for masonry. The insulation and/or cooling spaces built into these systems allow the back of the fireplace to be placed closer to combustible materials than their masonry counterparts.

Although most units are metal, pre-manufactured, modular, masonry fireplaces are also available. These masonry models incorporate special engineering techniques that are not used in most field constructed fireplaces, including a listed venting system. Like metal factory-built fireplaces, pre-manufactured masonry fireplaces reduce the clearance to combustibles and increase the amount of heat produced by the fireplace. These advantages, coupled with the lasting nature of masonry, make pre-cast refractory fireplaces and other modular masonry fireplace systems an attractive, but somewhat more expensive, alternative to the relatively inexpensive materials and construction of the mass-produced factory-built fireplace.

Q. What’s the safest way to use a factory-built fireplace?

Proper use is critical to safe and efficient operation of factory-built fireplaces. When you light a fire, keep in mind the following considerations:

• The damper must be fully open before starting a fire and left open until the fire is out. If a source for outside combustion air exists, be sure that it is open before you light the fire.
• Don’t overload the fireplace. If you do, burning logs could roll out. Never use wet or green wood.
• Be sure to close the screen to prevent sparks from flying out into your living room. Close the glass doors to reduce heat loss from the room into the chimney only when your fire is almost out. Glass doors on a factory- built fireplace must be tested and listed for that particular fireplace. It can be dangerous to use the wrong set of glass doors on your fireplace.
• Never start a fire with liquid fire starters, i.e. gasoline, kerosene, etc.
• Do not burn Christmas trees or a lot of paper in your fireplace. This type of fire, which gets very hot really quickly, can cause the joints of the chimney to separate or the metal to warp.
• Do not install a wood stove - whether free-standing or insert style - into a factory-built fireplace and chimney system, unless the insert you are using has been tested and listed for use with the fireplace and approved by the manufacturer of the chimney system (not the stove manufacturer alone). Installing an insert into a fireplace system that is not designed for either the weight of the unit or the intense heat the insert or stove produces could result in a house fire and will also void any warranty issued by the fireplace manufacturer.
• Annual inspection and sweeping, when required, of your fireplace and chimney is recommended by the National Fire Protection Association and the Chimney Safety Institute of America.

Q. How long will a factory-built fireplace last?

Factory-built fireplaces are decorative heating appliances. They are engineered with specific components that, when properly installed, will give you years of enjoyable use. Regular service and maintenance will help owners keep a step ahead of potential problems.

A factory-built unit will reach the end of its useful life when repair of the unit is no longer possible, particularly if the components that are necessary to maintain the listing are no longer available.

Q. How can I be sure the factory-built fireplace is installed correctly?

A factory-built fireplace is the only built-in home appliance which is not easily removed for inspection. It is important to take out a building permit before installing a factory built fireplace. The building inspector will conduct an examination to confirm that the system was installed according to code.

As always, reputable chimney professionals should be used when these units are purchased and installed. Local codes and the manufacturer’s installation instructions should be followed to the letter.

Q. Where can I install a factory-built fireplace?

Because metal factory-built units are relatively lightweight and do not require a footing. The reduced clearance between the fireplace and combustible materials, affords homeowners a wide range of design and placement choices.

Q. What if the lining of my firebox is cracked?

 Most factory-built fireplace manufacturers require replacement of the refractory panels of the firebox when a nickel, on end, can be inserted into the crack or when the surface of the refractory panel has abraded more than 1/4" from the original surface. Replacement of the refractory panels should be completed by a qualified professional familiar with factory-built fireplaces and the panel replacement procedures.

Q. What does a factory-built fireplace look like?

Factory-built fireplaces are available in styles as varied as housing styles around the world.

They can be finished with practically any material, allowing many design options. A homeowner may choose to finish the area surrounding the fireplace with a traditional full-surround mantle, painted or stained, in plain design or intricate scroll- work designs. They may choose to use a simple rough-hewn mantle of cedar or they may use stonework. The front face of the fireplace can be finished with a variety of materials, including tile or marble. Most factory-built fireplaces come in a black finish, although many manufacturers offer them dressed with brass trim.

Q. Can I have a gas log set installed in my factory built fireplace?

Yes, as long as the fireplace has a knock-out to allow the installation of a gas log lighter bar. Further it must be listed for use with solid fuel, and the listing cannot specifically exclude the installation of gas log sets. Unless the manufacturer of the fireplace specifically allows it, the installation of "vent-free" gas log sets are NOT allowed.   When allowed, the damper is blocked completely open and they are treated as a fully vented gas log set.

A few minutes spent understanding firewood will be time well spent, so please read on for general background information, as well as how to buy wood and store wood.

Seasoned Wood
All firewood contains water. Freshly cut wood can be up to 45% water!, while well seasoned firewood generally has a 20-25% moisture content. Well seasoned firewood is easier to start, produces more heat, and burns cleaner. The important thing to remember is that the water must be gone before the wood will burn. If your wood is cut 6 months to a year in advance and properly stored, the sun and wind will do the job for free. If you try to burn green wood, the heat produced by combustion must dry the wood before it will burn, using up a large percentage of the available energy in the process. This results in less heat delivered to your home, and literally gallons of acidic water in the form of creosote deposited in your chimney.

Wood is composed of bundles of microscopic tubes that were used to transport water from the roots of the tree to the leaves. These tubes will stay full of water for years even after a tree is dead. This is why it is so important to have your firewood cut to length for 6 months or more before you burn it, it gives this water a chance to evaporate since the tube ends are finally open and the water only has to migrate a foot or two to escape. Splitting the wood helps too by exposing more surface area to the sun and wind, but cutting the wood to shorter lengths is of primary importance.

There are a few things you can look for to see if the wood you intend to purchase is seasoned or not. Well seasoned firewood generally has darkened ends with cracks or splits visible, it is relatively lightweight, and makes a clear "clunk" when two pieces are beat together. Green wood on the other hand is very heavy, the ends look fresher, and it tends to make a dull "thud" when struck. These clues can fool you however, and by far the best way to be sure you have good wood when you need it is to buy your wood the spring before you intend to burn it and store it properly.

Storing Firewood
Even well seasoned firewood can be ruined by bad storage. Exposed to constant rain or covered in snow, wood will reabsorb large amounts of water, making it unfit to burn and causing it to rot before it can be used. Wood should be stored off the ground if possible and protected from excess moisture when weather threatens.

The ideal situation is a wood shed, where there is a roof but open or loose sides for plenty of air circulation to promote drying. Next best would be to keep the wood pile in a sunny location and cover it on rainy or snowy days, being sure to remove the covering during fair weather to allow air movement and to avoid trapping ground moisture under the covering. Also don't forget that your woodpile also looks like heaven to termites, so it's best to only keep a week or so worth of wood near the house in easy reach. With proper storage you can turn even the greenest wood into great firewood in 6 months or a year, and it can be expected to last 3 or 4 years if necessary.

Buying Firewood
Firewood is generally sold by volume, the most common measure being the cord. Other terms often employed are face cord, rick, or often just a truckload. A standard cord of firewood is 128 cubic feet of wood, generally measured as a pile 8 feet long by 4 feet tall by 4 feet deep. A face cord is also 8 feet long by 4 feet tall, but it is only as deep as the wood is cut, so a face cord of 16" wood actually is only 1/3 of a cord, 24" wood yields 1/2 of a cord, and so on.

Webster defines a rick simply as a pile, and truck sizes obviously vary tremendously, so it is very important that you get all of this straight with the seller before agreeing on a price; there is much room for misunderstanding. It is best to have your wood storage area set up in standard 4 or 8 foot increments, pay the wood seller the extra few dollars often charged to stack the wood, and warn him before he arrives that you will cheerfully pay only when the wood actually measures up to an agreed upon amount.

Another thought concerning getting what you pay for is that although firewood is usually sold by volume, heat production is dependent on weight. Pound for pound, all wood has approximately the same BTU content, but a cord of seasoned hardwood weighs about twice as much as the same volume of softwood, and consequently contains almost twice as much potential heat. If the wood you are buying is not all hardwood, consider offering a little less in payment.

Top Firewood Tips

It is far more important that the fuel be dry as compared to the species.

Do not burn any construction scraps of treated or painted wood, especially treated wood from decks or landscaping ties. The chemicals used can release dangerous amounts of arsenic and other very toxic compounds into your house.

If the "seasoned wood" you bought turned out to be pretty green and you elected to try to burn it anyway, be sure to have the chimney checked more often than usual, you may build up creosote very quickly. You don't have to burn only premium hardwoods. Less dense woods like elm and even soft maple are abundant and make fine firewood as long as you're willing to make a few extra trips to the woodpile.

If you have access to a variety of species, learn to manage your woodpile. Save the more dense fuel for the coldest months and use the "lighter" wood for kindling fires and during the spring or fall when you don't need as much heat.

Many people also have questions about burning artificial logs. Convenience is their strong suit and in general they are fine when time is an issue and you want a quick fire without all the muss and fuss of natural firewood. Usually they should be burned only one at a time and only in an open fireplace. One should be careful about poking them and moving them around once they are burning since they may break up and the fire may get a bit out of control. Be sure to carefully read the directions on the package.