BALANCING THE VENTILATION TIPS OF SAFE FIREPLACE REFERENCES In order for a fireplace, which utilizes OPERATIONS Published by the New York State Concrete Masonry Association natural draft to function properly, New York State Fire Prevention A fireplace fire, properly laid and fed and Building Code a supply of makeup air must be is easy to tend to and trouble free. Here available to replace the air exhausted is a good method for building a fire. National Fire Protection up the chimney. In older homes there Be sure the damper is open before Association, Quincy, MA is often enough leakage around doors lighting the fire! and windows to provide this air. In International Code Council Use a small amount of paper and newer, tighter homes another source International Building Code of air may need to be provided. Before a moderate number of kindling wood lighting the fire, use incense or a candle pieces to lay down the base. Place International Residential Code to determine if there is an updraft or a three small split logs directly on top. Country Club Hills, Illinois Space the logs to allow air to flow down draft in the chimney. If there is USA - Clay Flue Lining Institute no updraft try cracking open a window freely. National Concrete Masonry or door to provide a source of air to the Use wadded paper wand to light the RECOMMENDED PRACTICES FOR MASONRY room. If any problem persists you may fire. Hold the burning wand at damper Association, Herndon, VA FIREPLACE AND CHIMNEY CONSTRUCTION need to locate other sources of air level to start the draft, then lower it to Brick Industry Association of entering or being exhausted from the the paper/kindling stack. America, Reston, VA INTRODUCTION home. Exhaust fans and opening the As the kindling burns, add two or Illinois Masonry Institute, attic or upstairs rooms may be a source three pieces of wood - small logs are A well constructed masonry fireplace Park Ridge, IL of air flowing out of the building. Warm best at first. Stack the logs so that adds several elements of interest to the air tends to flow out from the upper the flames can get between them. Minnesota Masonry Institute home. Providing for not only a source floors and cold air flows in down lower Use larger logs when the fire is well Minneapolis, MN of warmth, masonry fireplaces add in the house. If you determine that you established. Masonry Institute of America, character, charm and value. As a result, need a permanent source of makeup The use of glass doors and screens Los Angeles, CA housing industry studies have shown air, contact a heating and ventilating is recommended for the safe and that masonry fireplaces are among specialist and discuss the various thermally efficient use of the fireplace. the top preferences of potential home options. Fireplaces will exhaust Keep screen closed when fire is buyers. The concrete masonry industry 400cfm to 1000cfm depending on size burning. Slow burning hard woods offers this Recommended Practice and intensity of the fire. to clarify the design and construction make the best fuel. Green wood gives NEW YORK STATE CONCRETE off less heat and can cause excess of masonry fireplaces in an effort to MASONRY ASSOCIATION REDUCING CREOSOTE BUILDUP creosote to build up in the chimney. assure quality, and safe construction One method for reducing creosote When ashes build up under the grate, that meets or exceeds the requirements buildup is to gradually stoke a medium all but a base layer about 1 inch thick of local and national building codes. hot fire for 15 to 30 minutes at least should be removed. Never use a Following the guidelines contained once a day, which tends to burn off the fireplace as an incinerator. in this publication will assure quality, creosote in small amounts. Seasoned For commercial or industrial safety, practicality, ease of construction or dry wood will form less creosote appliance applications please consult 347 McKennan Rd. and code compliance. These guidelines deposits than unseasoned or wet the local code. The recommendations, Frankfort, NY 13340 are a compilation of information from wood. In mild weather, frequent slow suggestions, statements, and technical Phone 315.254.0518 manufacturers, engineers, contractors, burning of the fireplace will severely data in this tech sheet are based on our Fax 315.883.1342 technical agencies and building code aggravate the creosote problem. best knowledge at the time of printing. Email ncarparelli@nys-cma. officials. Always check with your local Frequent inspection of the chimney They are given for informational code enforcement official prior to flues is important, especially during the purposes only and without any Copyright* 2011 New York State construction of your fireplace. first season Any problems that may be responsibilities for their use. Concrete Masonry Association, Inc. occurring can be corrected before they All Rights Reserved. become hazards. Inspect chimneys CODE ENFORCEMENT NOTIFICATION SIZE OF FIREPLACE from the roof using a flashlight, or Careful consideration should be The code enforcement official shall use a mirror to look up through the given to the size of the fireplace chimney flue. Any time an inspection be notified by the purchaser of any best suited to the room in which it is shows soot or creosote buildup the purchase or acquisition of any solid other important areas such as the located. This is important not only from CHART NO. 1 chimney should be cleaned. fuel burning heating appliance, or foundation, hearth, firebox, and smoke chimney construction materials. the fireplace’s appearance, but from its operation as well. If it is too small chamber. Some of these important CAUTION: The use of chemicals which All businesses selling or installing items are expanded upon below. Also Fireplace Opening Size of Room it will not produce a sufficient amount Width in Inches in Feet are supposed to clean the chimney solid fuel burning heating appliances, see the enclosed drawing details for when they are placed on a fire could and or chimney construction materials of heat, even though it functions further clarification. 24 to 32 10 x 14 produce heat intense enough to cause shall notify the purchaser(s) in writing properly. Follow Chart No. 1 as a guide 32 to 36 12 x 16 damage to the concrete masonry and at the time of sale or acquisition that in selection of the size best suited for 36 to 40 12 x 20 clay flue liners which contribute to the they are legally required to notify their your application. 40 to 48 14 x 28 deterioration of these elements. local code enforcement official before Please read the entire tek 48 to 60 16 x 30 installation or erection commences. After selecting the appropriate spec 3.5 before proceeding 48 to 72 20 x 26 Please accept this Tek Spec 3.5 as size of the fireplace, consideration with design and construction. and official written notification of the in planning is necessary for several above. 8 1 BEFORE WE START combustible elements offer support SMOKE CHAMBER Masonry fireplaces are site built to the hearth or fireplace. The smoke chamber located and offer the unique ability for infinite For fireplaces up to 6 sq. ft. (or directly above the firebox shall be variability and individual expression. an opening of approximately 3’ x 2’) constructed of minimum 2” thick Two specific designs are detailed in the hearth extension must project 16 firebrick, a manufactured vitrified clay this guide, the Standard Fireplace and inches in front of the fireplace and smoke chamber, or 4” solid masonry. the Rumford Fireplace. The Standard 8 inches beyond each side of the A 1/2” to 3/4” thick parged refractory fireplace (see p. 4-5) has a short fireplace opening. For larger sized may be required over corbeled firebox with the back wall leaning openings these dimensions increase firebrick to form a smooth surface to forward. The Rumford Fireplace (see to 20 inches in front and 12 inches easily transition smoke and gases up through the smoke chamber. (Refer p. 6-7) is tall with widely splayed on the sides. The fireplace hearth to drawings for minimum total wall sidewalls and an aerodynamic curved and sidewalls are constructed of a thickness). throat that improves draft and reduces minimum of 2 inches of firebrick laid The smoke chamber, for Standard in refractory mortar. Note the firebox emissions. The heating ability of the Fireplace Design, shall be constructed is surrounded by 4 inch solid block Rumford is legendary. The ease of so the sidewalls and front wall taper construction, and the visual appeal of for structural stability and thermal inward to form the support of the the tall opening makes the Rumford heat storage (refer to drawings fireplace chimney. The chimney shall a very popular feature with architects for minimum total wall thickness). be positioned so that it is centered and home builders. Firebrick made to the specifications on the width of the fireplace and the Although there are many design listed will provide minimal expansion back of the flue liner is aligned flush variations that are quite acceptable and contraction throughout the with the vertical rear surface of the for masonry fireplaces, the same operating temperature of residential smoke chamber. This configuration principles of construction apply fireplaces and chimneys. Therefore, provides for smooth uninterrupted to all designs as outlined in no allowance to accommodate exiting of smoke and gases from the this specification. Of particular movement of firebrick is included. fireplace into the chimney. NOTE: The importance are minimum clearance All firebrick must be installed in Rumford throat and Smoke Chamber to combustibles, building codes and refractory mortar. The back side are usually made of preformed parts. specifications of materials. of the firebox shall be parged with (See p. 6-7). Follow the manufacturers Again please read this entire mortar adding to its strength. Regular instructions. specification for help to assure a masonry mortar may be used here. CHIMNEY quality fireplace installation. The fill behind the firebox shall be non- The chimney is constructed directly combustible rubble or solid masonry. on the smoke chamber. The chimney FOUNDATION consists of a flue liner and chimney The foundation consists of concrete PLACEMENT OF THE wall. The chimney wall shall be footings and masonry walls. Minimum DAMPER AND LINTELS constructed so there is at least a 4 inch code requirements must be met Metal parts have a greater coefficient nominal thickness of solid masonry with respect to foundation and wall of expansion than masonry units. between the flue liner and any exterior design. Unless specifically designed Room for expansion or movement surface. Solid masonry products for for additional loads, no other part of must therefore be provided. The the chimney wall construction are the structure or adjoining structure damper should be laid on top of the those (brick, block, or stone) which are either 100% solid or those which have should be supported by the chimney. firebox in a bed of refractory mortar cores or holes of any configuration Immediately above the foundation only thick enough to assure a level which do not exceed 25% of the wall, support for the combustion damper installation. A 1/8” to 1/4” space should be left at the ends of gross cross sectional area of any load chamber and the extended hearth surface. The chimney shall be the damper flanges. The damper bearing is provided by a cast in place or separated from the flue liners by an air shall not support any masonry. Any precast concrete slab. The forming space no greater than the thickness of fireplace lintel shall be installed in a of the concrete slab requires that the clay flue liner. This will assist the openings be included for outside similar manner on a bed of mortar (for clay flue to stay in alignment as well combustion air vents and ash dumps. leveling purposes) with a 1/8” to 1/4” as permit the clay flue to expand or If a permanent form is used it must be space on sides and ends. This space contract freely. non-combustible, (i.e. steel, slate, or may be filled with non-combustible All spaces between chimneys and corrugated metal). The concrete slab soft material such as fiberglass floors and ceilings through which the must not support the floor system. insulation or refractory blanket. chimneys pass shall be firestoppped Any masonry corbeled from the with non-combustible material. The FIREBOX AND HEARTH firebox shall not bear on the damper firestopping of spaces between All materials used to construct the assembly. To prevent this, a second chimneys and wood joists, beams, or firebox, hearth, and extension must lintel may be installed with the same header shall be galvanized steel not be completely non-combustible provisions for thermal expansion and less than 26 gauge or non-combustible masonry materials. Brick or stone the lintel installed above the fireplace material not thinner than 1/2 inch . Clay are most popular. In no instance may opening. flue liners shall be installed bedding

2 7 one on the other in refractory mortar The cap shall never be cast tightly G. Clay Flue Liners - Clay Flue Lining with close fitting joints left smooth against the flue liner. A gap should be Institute and ASTM C-315, C-1283 on the inside and outside face of the left to accommodate expansion and H. Firebrick - ASTM C-27 or C-1261 flue liner. Depending on the size and contraction of the flue lining. The gap low duty 2” thick minimum. design of the chimney the mason at the top between the cap and flue may choose to install an additional liner should be sealed with caulk to I. Refractory mortar - Non water wythe or by other accepted methods prevent entrance of water into the soluble refractory mortar is best (i.e. corbel header construction, etc.) chimney. This is a maintenance joint for installing both firebrick and clay to insure the structural integrity of the that should be checked on a regular flues. Homemade mixes combining clay flue lining. The flue lining and basis to insure water tightness and fireclay and mortar simply do not surrounding masonry shall touch only replaced when necessary. meet the code. Refractory parge for in spot locations (not to exceed two The use of quality polysulfide, smoke chamber must also be non- inches square each) to assure proper butyle, or silicone rubber caulking water soluble. See manufacturers alignment and support. In no case compound is recommended. Oil instructions. All above must meet will the clay flue liner be encased based sealants do not perform well the high temperature requirements completely around its circumference here. Backer rod also is suggested to of ASTM C-199 medium duty. at one location. Clay flue liners made to support caulk around flue. the listed specifications may expand J. Dampers - should be certified or contract during the operating to have air infiltration losses not to temperatures of residential fireplaces FLASHING exceed 20 cubic feet per minute and chimneys. This publication allows Base flashing and counter flashing when in the closed position. are installed at the chimney/roof for such movement. K. Steel Angle - meeting ASTM interface. The base flashing is installed When more than one flue is contained A-36 with minimum dimensions as first on the faces of the chimney in a chimney, a separation shall be specified in chart 11. provided between adjacent flues. The perpendicular to the ridge line with separation shall be constructed of tabs at each corner. The flashing shall CLEARANCE TO COMBUSTIBLES extend a minimum of 4 inches up the solid masonry wythes (walls) not less One of the most important fire roof. Counter flashing is then installed than 4 inches, nominal, in thickness safety requirements is the air space over the base flashing. It is inserted and the wythes shall be bonded to that separates the chimney from into the mortar joint for 3/4 to 1 inch the chimney wall with either ties or combustible materials such as and mortared solidly into the joint. masonry mortar. framing. For interior chimneys this The counter flashing shall lap the The chimney must extend at least 2 space must be 2 inches minimum. base flashing by at least 3 inches. If feet above the highest point where it For an exterior chimney this space the flashing is installed in sections, the passes through the roof. In addition, must be 1 inch minimum. This flashing higher up the roof line shall the top of the chimney should be space insulates the chimney from lap over the lower flashing a minimum at least 2 feet above any portion of transferring heat to the combustible of 2 inches. All joints in the same base the building that is within 10 feet of materials and must not be filled flashing and counter flashing shall be the chimney. Good draft is normally except for required firestopping. When thoroughly sealed. The unexposed achieved if the chimney height is such masonry fireplaces and chimneys are side of any bends in the flashing shall that the vertical distance from the top part of a masonry wall combustible also be sealed. of the fireplace opening to the top of materials shall not be in contact with the chimney is at least 15 feet. If the the masonry less than 12 inches from chimney is less than 15 feet, a larger the outside surface of the flue lining clay flue size should be considered MATERIAL SPECIFICATIONS Use only those materials conforming or firebox. than what is required for a chimney of Exposed combustible trim and the 15 feet or more. to the following specifications. A. Concrete Block - conforming to edges of sheathing materials such ASTM C-90 Grade N, ASTM C-129 as wood siding, flooring and drywall shall be permitted to abut fireplace CHIMNEY CAP B. Mortar Mix - ASTM C-270 Type N and chimney walls provided they are Every masonry chimney should at least 12 inches from the inside have a chimney cap to terminate the C. Concrete Mix - for hearth slab surface of the fireplace or flue lining. masonry and protect the chimney. and chimney cap should conform to Woodwork or other combustible This cap can be precast concrete or ASTM C-39 materials shall not be placed within cast in place concrete. D. Brick - ASTM C-55 (or 216 Grade- 6 inches of the fireplace opening. The chimney cap shall extend SW) Combustible material within 12 inches beyond the exterior face of the of the fireplace opening shall not masonry and incorporate a drip slot E. Caulking - Polysulfide, Butyl or project more than 1/8 inch for each 1 or other characteristic, to prevent Silicone Rubber inch distance from such opening. moisture penetration from the top of F. Flashing - Corrosion resistant the masonry wall to the chimney. metal. No aluminum

6 3 BALANCING THE VENTILATION TIPS OF SAFE FIREPLACE REFERENCES In order for a fireplace, which utilizes OPERATIONS Published by the New York State Concrete Masonry Association natural draft to function properly, New York State Fire Prevention A fireplace fire, properly laid and fed and Building Code a supply of makeup air must be is easy to tend to and trouble free. Here available to replace the air exhausted is a good method for building a fire. National Fire Protection up the chimney. In older homes there Be sure the damper is open before Association, Quincy, MA is often enough leakage around doors lighting the fire! and windows to provide this air. In International Code Council Use a small amount of paper and newer, tighter homes another source International Building Code of air may need to be provided. Before a moderate number of kindling wood lighting the fire, use incense or a candle pieces to lay down the base. Place International Residential Code to determine if there is an updraft or a three small split logs directly on top. Country Club Hills, Illinois Space the logs to allow air to flow down draft in the chimney. If there is USA - Clay Flue Lining Institute no updraft try cracking open a window freely. National Concrete Masonry or door to provide a source of air to the Use wadded paper wand to light the RECOMMENDED PRACTICES FOR MASONRY room. If any problem persists you may fire. Hold the burning wand at damper Association, Herndon, VA FIREPLACE AND CHIMNEY CONSTRUCTION need to locate other sources of air level to start the draft, then lower it to Brick Industry Association of entering or being exhausted from the the paper/kindling stack. America, Reston, VA INTRODUCTION home. Exhaust fans and opening the As the kindling burns, add two or Illinois Masonry Institute, attic or upstairs rooms may be a source three pieces of wood - small logs are A well constructed masonry fireplace Park Ridge, IL of air flowing out of the building. Warm best at first. Stack the logs so that adds several elements of interest to the air tends to flow out from the upper the flames can get between them. Minnesota Masonry Institute home. Providing for not only a source floors and cold air flows in down lower Use larger logs when the fire is well Minneapolis, MN of warmth, masonry fireplaces add in the house. If you determine that you established. Masonry Institute of America, character, charm and value. As a result, need a permanent source of makeup The use of glass doors and screens Los Angeles, CA housing industry studies have shown air, contact a heating and ventilating is recommended for the safe and that masonry fireplaces are among specialist and discuss the various thermally efficient use of the fireplace. the top preferences of potential home options. Fireplaces will exhaust Keep screen closed when fire is buyers. The concrete masonry industry 400cfm to 1000cfm depending on size burning. Slow burning hard woods offers this Recommended Practice and intensity of the fire. to clarify the design and construction make the best fuel. Green wood gives NEW YORK STATE CONCRETE off less heat and can cause excess of masonry fireplaces in an effort to MASONRY ASSOCIATION REDUCING CREOSOTE BUILDUP creosote to build up in the chimney. assure quality, and safe construction One method for reducing creosote When ashes build up under the grate, that meets or exceeds the requirements buildup is to gradually stoke a medium all but a base layer about 1 inch thick of local and national building codes. hot fire for 15 to 30 minutes at least should be removed. Never use a Following the guidelines contained once a day, which tends to burn off the fireplace as an incinerator. in this publication will assure quality, creosote in small amounts. Seasoned For commercial or industrial safety, practicality, ease of construction or dry wood will form less creosote appliance applications please consult 347 McKennan Rd. and code compliance. These guidelines deposits than unseasoned or wet the local code. The recommendations, Frankfort, NY 13340 are a compilation of information from wood. In mild weather, frequent slow suggestions, statements, and technical Phone 315.254.0518 manufacturers, engineers, contractors, burning of the fireplace will severely data in this tech sheet are based on our Fax 315.883.1342 technical agencies and building code aggravate the creosote problem. best knowledge at the time of printing. Email ncarparelli@nyscma. officials. Always check with your local Frequent inspection of the chimney They are given for informational www.nyscma.org code enforcement official prior to flues is important, especially during the purposes only and without any construction of your fireplace. first season Any problems that may be responsibilities for their use. Copyright* 2012 New York State occurring can be corrected before they Concrete Masonry Association, Inc. become hazards. Inspect chimneys CODE ENFORCEMENT All Rights Reserved. NOTIFICATION SIZE OF FIREPLACE from the roof using a flashlight, or Careful consideration should be The code enforcement official shall use a mirror to look up through the given to the size of the fireplace chimney flue. Any time an inspection be notified by the purchaser of any best suited to the room in which it is shows soot or creosote buildup the purchase or acquisition of any solid other important areas such as the located. This is important not only from Chart No. 1 chimney should be cleaned. fuel burning heating appliance, or foundation, hearth, firebox, and smoke chimney construction materials. the fireplace’s appearance, but from its operation as well. If it is too small chamber. Some of these important CAUTION: The use of chemicals which All businesses selling or installing Fireplace Opening Size of Room it will not produce a sufficient amount items are expanded upon below. Also are supposed to clean the chimney solid fuel burning heating appliances, Width in Inches in Feet of heat, even though it functions see the enclosed drawing details for when they are placed on a fire could and or chimney construction materials further clarification. produce heat intense enough to cause shall notify the purchaser(s) in writing properly. Follow Chart No. 1 as a guide 24 to 32 10 x 14 32 to 36 12 x 16 damage to the concrete masonry and at the time of sale or acquisition that in selection of the size best suited for 36 to 40 12 x 20 clay flue liners which contribute to the they are legally required to notify their your application. 40 to 48 14 x 28 deterioration of these elements. local code enforcement official before Please read the entire tek 48 to 60 16 x 30 installation or erection commences. After selecting the appropriate spec 3.5 before proceeding 48 to 72 20 x 26 Please accept this Tek Spec 3.5 as size of the fireplace, consideration with design and construction. and official written notification of the in planning is necessary for several above. 8 1 4 5

Masonry Bake Oven Tek Spec 3.5

Wood fired ovens constructed of masonry materials have been used for cooking and baking for many centuries. In the last decade we see increased interest in a variety of masonry oven designs for commercial and residential applications for both indoors and outside. We offer this sketch (as an addendum to Tek Spec 3.5) as a possible design or a place to start for your installation. Many designs are available of varying sizes and shapes. Some are built from individual masonry construction throughout and some are built from pre-engineered and manufactured component parts. No matter the design, masonry products for foundation, internal components, and veneers (ie brick, block, firebrick, mortar, refractory components, stucco, stone, terra cotta and etc.) are available from your local masonry supplier. Seek their advice. Seek further information from the internet. As with all masonry construction we encourage fire safety and code compliance. plan view @ chimney

SECTION/ELEVATION SECTION/ELEVATION MASONRY BAKE OVEN