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Fireplace Inspections
Fireplace Inspections

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Fireplace Inspections Made Easier 1901 N. Moore St. Arlington, VA 22209 (703) 524-8030

Hearth, Patio & Barbecue Education Foundation National Fireplace Institute

Challenges our industry presents Importance to public safety Why discuss fireplace inspections?

Products are Constantly Changing New product offerings Various installation applicationsVenting systems and venting configurationsChallenges

C h allenges Variety of Code Issues Combustion airUse of room Authority for venting instructionsMobile home requirements

C h allenges Manufacturers’ Instructions Installation requirements differManufacturer to manufacturer Model to modelInconsistent organizationInconsistent terminology

C h allenges Inspectors Numerous responsibilities Lack of time

Improper Installation May result in: Poor PerformanceVoiding of Listing and Warranty –Assumption of All Liability Loss of Property and Life

Reference Manuals

W e o f fer the following Inspection as a guideline, not as a requiredlist of inspection areas.

Categorizing AppliancesGeneral Concerns Gas AppliancesWood Burning AppliancesPellet Appliances AccessoriesInspection

1. Categorizing AppliancesInspection

Hearth Appliances V enting Meth o d Appliance Type A p pl i ance Standard C ategorizing Hearth Appliances Fuel T y p e

Fuel Type Solid Fuel Gas C ategorizing Hearth Appliances Natural Gas Liquid Propane W ood Coal Biomass Electric

Hearth Appliances Appliance Type C ategorizing Hearth Appliances

Masonry Fireplace

Factory Built Fireplace

Gas Log Sets

Fireplace Inserts

Free Standing Stoves

Hearth Stoves

MasonryFurnaces Outdoor

Categorizing By Venting Type Gas Venting Systems Conventional Vent Direct Vent Unven t ed

Categorizing By Venting Type Gas Conventional Vent B - V en t Chimneys Masonry or Factory-Built Li n ers

Categorizing By Venting Type Gas Direct Vent PVC Hi-efficiency condensing Coaxi a l Co-linear

Categorizing By Venting Type Woodburning Venting Systems 1700 ° 2100 ° “HT” Masonry Chimneys Lin e rs Factory-Bui l t Chimneys

Categorizing By Venting Type Pellet Venting Systems Li ners Type L Pellet Pellet DV

Vented Gas Hearth Appliances NOT Efficiency Tested(“Decorative”) Efficiency Testing (“Heating”) Gas Log Sets Gas Fireplace Gas Fireplace Heaters Gas Standards

Categorizing By Venting Type Gas Direct Vent PVC Hi-efficiency condensing Coaxi a l C o -li n e a r

Unvented Gas Hearth Appliances Gas Logs Fireplaces Freestanding Stoves Gas Standards

Gas Standards

Vented Gas Fireplace ANSI Z21.50, CSA 2.33 Appliances: (Not tested for efficiency) •Fireplaces•Fireplace inserts•Freestanding stoves Requirements • Safety pilot • Spill switch if equipped with draft hood Restrictions • No thermostat Options • Listed blowers

Vented Gas Fireplace Heater ANSI Z21.88, CSA 2.33Appliances: (Tested for efficiency) •Fireplaces•Fireplace inserts•Freestanding stoves Requirements • Safety pilot • Spill switch if equipped with draft hood Restrictions • None Options • Listed blowers • Thermostats

Decorative Gas Accessory inSolid Fuel Fireplaces Appliances: ANSI Z21.60, CSA 2.26•Log SetsRequirements• Safety pilot•Working fireplace and chimney • Permanent damper opening • Fireplace screen • Cleaning of venting system Restrictions • No thermostat Options • Listed blowers

Manually Lighted, Natural Gas Appliances for Installation in Solid-fuel Burning Fireplaces ANSI Z21.84 Appliances:Log Sets RequirementsWorking fireplace and chimneyPermanent damper opening Fireplace screen Cleaning of venting system Restrictions No thermostat

Unvented Gas Room Heater ANSI Z21.11.2a Appliances: •Fireplaces•Fireplace inserts •Freestanding stoves Requirements • Safety pilot w/ODS Restrictions • Bedroom, Bathroom, Confined space • Tight construction • Maximum 40,000 Btu/hr input Options • Listed blowers • Thermostats

Solid Fuel Standards Underwriter’s Laboratories (UL) Materials and constructionFire and strength testsReview of installation instructions

Solid Fuel Standards Solid Fuel Appliances Open Chamber Factory Built Fireplaces Closed Chamber High Efficiency Fireplace Stoves F r ee s tand i ng Stoves Hearth Stoves Fireplace Inserts High Efficiency Factory Built Fireplaces

UL 127 Factory Built Fireplaces Testing requirements for entire system Fire chamberChimney Roof assemblyRelated components

UL 127 Factory Built Fireplaces Standard factory-built chimney test Sustained temperature of 1000°FTen minute test at 1700°FOptional Type HT testSustained temperature of 1000°F 3 - ten minute tests at 2100 ° F Not required for factory-built fireplaces

Installation Manual

Safety Label

2. General ConcernsInspection

Combustibles Combustible: Walls with wood framingPaper-faced materials Papered sheetrock (dry wall)– including fire-rated papered sheetrock Plaster on wood lath or studs

Com b ustibles Noncombustible Entirely metalBrickTile ConcreteSlate Plaster on metal lath

Safety Testing

Clearances

Cleara n ces Side Clearance Back Clearance Bottom ClearanceAlso mantle, surround, ceiling and adjacent walls

Cleara n ces Header Size Orientation – Flat or on edge

Clearances

Cleara n ces Standoffs -Top

Cleara n ces Standoffs -Side

Cleara n ces Standoffs -Bottom

Clearances Nailing flanges

Clearances Instruction Manual

Clearances Instruction Manual

ClearancesSafety Label

ClearancesWarning Labels

ClearancesWarning Labels

Clearances Wall Protection Reducing listed clearancesApproved site-built systems Listed manufactured systemsClearance reduction systems can NOTreduce clearance to less than 12" Clearances less than 12" can only be listed clearance, specific by manufacturer.

Clearances Wall Protection Protection Wall Ceiling 3½ " masonry wall / NO ventilation 33% ½ " noncombustible board over 1" insulation, NO ventilation 50% 33% Min. 24 gage sheet metal / spaced out 1 " 66% 50% 3½ " masonry wall / spaced out 1 " 66% ½ " noncombustible wall board spaced out 1 " 66% 50% Listed prefabricated systems Manufacturer instructions

Clearances Wall Protection 1" air space gives greatest reductionConverts radiant energy to convection heat Rising warm air pulls in cool air 12

Vent System Purposes Remove combustion by-products Protect combustibles from heatAirspace Remember: combustibles can ignite with nocontact from flame Obtain adequate combustion air

House Pressure Conditions Sources that exhaust air:Kitchen range fansClothes dryersCentral vacuum Gas furnaceWater heaters Recessed lighting Additional hearth appliances, -especially open fireplace Photo compliments of CSIA Outside air Open fireplaces require 200-300 cfm EPA woodstoves require 11-32 cfm 4”outside air brings in about 10 cfm of air

65 House Pressure Conditions House Stack EffectHeated portion of house taller than vent terminationOpen window in upper portion create greater chimney effect than vent

Combustion Air Co mbustion air:(Primary Air)Dilution air: Excess air: (Secondary Air) Air introduced into draft hood and mixed with flue gases. Moderates draft and reduces vent temperatures Air provided for combustion that mixes with the gas. Air that that does not combine with fuel in the combustion process

Combustion Air Air changes perhour (ACH):construction: Percent of volume exchanged (outdoor air replacing indoor air). Continuous water vapor retarder Unusually tight Storm windows Weather-stripping Caulking/sealing of gaps Example: 0.35 ACH = 35% of volume of indoor air is replaced by outdoor air every hour.

Unconfi n ed spac e: Space with volume 50 cubic feet or more per 1000 Btu/hr. Confined Space with volume less than space: 50 cubic feet per 1000 Btu/hr Combustion Air Rooms communicating through openings without doors are part of unconfined space.

KAIR Method: K nown Air Infiltration R ateAir Exchange rate is knownMust be used if .40 or less May be used if between .40 & .60 Standard Method: Air exchange rate is not known. 2002 – 2009 Fuel Gas Codes Combustion Air

2002 – 2009 Fuel Gas Codes KAIR Method 60,000 Btu/hr natural draft gas fireplace in room 15' x 25'with 9' ceiling in house with 0.40 ACHFormula: 21 divided by .40 = 52.5 [60,000 divided by 1,000 = 60] 60 x 52.5 = 3,150 cubic feet Available volume in room: 15 x 25 x 9 = 3,375 Indoor air OK because volume is more than required 3,150 cubic feet

2002 – 2009 Fuel Gas Codes Standard Method Minimum volume necessary: 39,000 BTU appliance50 cu. Ft for every 1,000 BTU’s39,000 BTU’s / 1,000 = 3939 * 50 = 1950 cu. Ft Divide input rating Btu/hr by 20 1,000 / 50 = 20 39,000 BTU appliance / 20 = 1950 cu. Ft Room volume 1,950 or greater is OK Room volume less than 1,950 is not OK (I.E. Room size 21x12x8=2016 cubic feet = OK)

2002 – 2009 Fuel Gas Codes Standard MethodMaximum Btu/hr rating Room15x18x8 = 2,160 cu. Ft 50 cu. Ft for every 1,000 BTU’s 2,160 cu. Ft. / 50 = 43.2 (43,200 BTU’s) Multiply the volume by 20 2,160 cu. Ft. * 20 = 43,200 BTU’s Space OK for appliance with 43,200 Btu/hr or less Space not OK for appliance with more than 43,200 Btu/hr

2002 – 2009 Fuel Gas Codes Combustion AirBedroom/Bathroom -Unvented Confined space Not allowedUnconfined space 1 wall-mounted heater No more than 6,000 Btu/hr in bathroom No more than 10,000 Btu/hr in bedroom 2002-> Gas logs allowed with means to mount burner base to floor of solid-fuel fireplace

2002 – 2009 Fuel Gas Codes Combustion AirAdjoining Rooms Minimum free area of 1 sq. in./1,000 Btu/hr Not less than 100 sq. in. One opening commences within 12 in. of ceiling within 12 in. of floor

2002 – 2009 Fuel Gas Codes Combustion Air Different StoriesMinimum free area of 2 sq. in./1,000 Btu/hr Not less than 100 sq. in.

2002 – 2009 Fuel Gas Codes Combustion Air OutdoorTwo Openings: Directly or Vertical DuctsOne within 12” of ceiling One within 12” of floor can be from ventilated attic can be from ventilated crawl space Minimum 1 sq. in. per 4,000 Btu/hr

2002 – 2009 Fuel Gas Codes Combustion Air OutdoorTwo Openings: Horizontal Ducts One within 12” of ceiling One within 12” of floor Minimum 1 sq. in. per 2,000 Btu/hr

2002 – 2009 Fuel Gas Codes Combustion Air OutdoorOne Opening Within 12” of ceiling Communicates with outdoors Directly Through ducts Spaces that freely communicate with outdoors Minimum 1 sq.in./3,000 Btu/hr Not less than sum of areas of all ve nt connectors

2002 – 2009 Fuel Gas Codes Combustion Air: Summary Indoor Adjoining room 2 Openings 1 in² per1,000 BTU’s 12” of ceiling 12” of floor At least 100 in² Indoor Different story 2 in² per 1,000 BTU’s At least 100 in² Outdoor Direct or Vertical 2 Ducts 1 in² per 4,000 BTU’s May be from ventilated attic or ventilated crawl space 12” of ceiling 12” of floor Outdoor Horizontal Ducts 2 Openings 1 in² per2,000 BTU’s 12” of ceiling 12” of floor OutdoorOne Duct or Direct Opening1 in² per3,000 BTU’sNot less than the sum of the areas of allvent connectors

2002 – 2009 Fuel Gas Codes Combustion AirSource of Air Including adjacent spaces that cannot be closed off May now use a combination of openings to indoor spaces outdoors

Combustion AirOpening Size Calculation60,000 Btu/hr gas fireplace 12 x 15 x 8 room Determine total room volume: 12 x 15 x 8 = 1,440 cu. ft.Determine required volume by standard method: 60,000/20 = 3,000 cu. ft required 1440/3000=48% The room is able to provide 48% of the necessary air. We need to bring 52% in from outside. Determine overall opening size:(1 sq. in/3,000 BTU’s) 60,000/3,000 = 20 sq. In. (1 duct direct to outdoors) Determine minimum outdoor air opening: 20 x 52% = 10.4 sq. In.

Combustion Air Metal: 75% free area Screens: mesh size mustnot be smaller than 1/2" Louvers and GrillesW ood Size based on net free area Calculation Wood: 25% free area Metal 6"x10" = 60 x .25 = 15 sq. in. 10"x6" = 60 x .75 = 45 sq. in.

Combustion Air Combustion Air from Outside Combustion Products Vented to Outside Direct VentCombustion air requirements do NOT apply

Combustion Air Passive: Non-mechanical (no fan) InfiltrationGaps in building envelopeOutside air kit May be required May not be reliable source due to influence of pressure conditions inside and outside house – Flow reversal of air and combustion products possible in certain situations

Combustion Air Outside Air Kits High enough to avoid blockage– snow, leaves, debris Never from garage or space where combustible liquids stored Never from attic or position above flue gas outletDuct as short and straight as possible Follow manufacturer’s instructions for materials, length, height, location

Combustion Air Decorative Fireplaces (UL 127 or UL 737) NFPA 211Outside air where required by AHJListed component installed to instructions Not from Attic Basement Garage Another interior space

Combustion Air Decorative Fireplaces (UL 127 or UL 737) IRCExterior air supply unless room mechanically ventilated/controlled to neutral or positive pressureOK from ventilated attic or crawl spaceNot From Garage Basement Elevation higher than firebox

Combustion AirPowered Make-up Air System Fan and ductwork to make up difference between available and neededSpecifications determined by house pressure testDepressurization level from exhaust devicesHearth appliance tolerance Avoid bringing in more unheated air than needed

Combustion AirDiffuser DuctheaterInterlock and speed controlIn line fan Insul atedduct 24VACdamper Outdoor Weather hood

Mobile Home Requirements HUD Requirements Outside air attached directly to applianceMechanically attached to floor No installation in sleeping room Listed chimney with spark arrestorUL 127 and 1482 Maintain structural integrity of home Manufacturers’ Instructions Some require electrical grounding to chassis

NFPA 211 Inspections Definitions Readily accessible: Exposed for inspection without tools to open or remove doors, panels, coveringsAccessible: Exposed for inspection without doing damage, but may require tools Non-accessible, concealed:Inspection requires damage to chimney, building structure or finish, and/or use of special tools

NFPA 211 Inspections Level 1 CircumstanceReplacement of connected appliance with one of similar type, input rating, & efficiency Level of access Readily accessible portions of chimney exterior & interior; accessible portions of appliance & chimney connection

NFPA 211 InspectionsLevel 1 Scope Readily accessible areas of chimney, structure, and flue Lack of obstruction or creosote in flueBasic appliance installation and connection

NFPA 211 Inspections Level 2 CircumstanceAddition of appliance Replacement with appliance of dissimilar typeSale or transfer of propertyOperating malfunction or external event likely tohave caused damage to chimney Level of Access Accessible portions of chimney & appliance Video scanning or other means of inspection

NFPA 211 Inspections Level 2 ScopeAll subjects of level 1 Proper construction and condition of accessible portions of chimney structure and enclosed fluesSize and suitability of flues for connectedappliances

NFPA 211 Inspections Level 3 CircumstancesInvestigation of incident that has caused damage to the chimney or building Hazard detected or suspected as a result of level 1 or 2 inspection cannot be fully evaluated without access to concealed areas

NFPA 211 Inspections Level 3 Level of accessInternal and external portions of chimney structure, including concealed areasRemoval of building or chimney components Removal only as needed to gain access to areas subject to inspection

NFPA 211 Inspections Level 3 ScopeAll subjects of level 1 and 2 inspections Proper construction and condition of concealed portions of chimney structure and enclosed fluesProper clearances from combustibles

NFPA 211 Inspections Level Circumstance Level of AccessScope 1 Replacement with similar type, input, efficiency Readily Accessible Obstructions Deposits 2 Add/replace dissimilar Sale of property Malfunction Accessible Construction/ condition Clearances/ suitability 3 Hazard suspected Need access to concealed areas Can include removal of bldg. /chimney compon e nts Includes access to concealed areas

Green Building Codes Define additional approaches to construction – Referred to as “overlay” or “reach” codes and standards that extend, but do not conflict with basic codes and standardsDirect impact with some hearth productsIndirect or upcoming impact in relationship to air tightness of building envelope or indoor air quality concerns

Green Building Codes International Energy Conservation Code IECC 2009 & IRC 2009“New wood-burning fireplaces shall have gasketed doors and outdoor combustion air.”IECC 2012 & IRC 2012 “New wood-burning fireplaces shall have tight-fitting flue damper and outdoor combustion air.” Section 402.4.1.1 & IRC N1102.4.1.1 – “Fireplaces shall have gasketed doors.”

Green Building CodesInternational Energy Conservation Code Material(s) assembled and joined together to provide a barrier to air leakage through the building envelope. An air barrier may be a single material, or a combination of materials. – Fireplace walls must include an air barrier

3. Gas Appliance Installation IssuesInspection

Appliance Standards YES Z21.60 Gas LogSets Z21.50Gas Fireplaces Z21.88 Gas F irep l ace Heaters Z21.11.2 Un v e nted Room Heater Class 4 Conden s ing Appliances AFUE Tested NO NO YES NO YES Thermostat NO NO YES YES OPTION Fireplace, Insert, Stove NO YES YES YES YES Vent switch: Draft hood units NO YES YES NO NO ODS equipped * NO NO YES NO

Shutoff Valve Exceptions Readily accessible Permanently identifiedServes no other equipmentReadily accessible Having direct access without the need of removing or moving any panel, door, or similar cover Accessible Having access to but which first requires the removal of a panel, door, or similar covering

Shutoff Valve Exceptions National Fuel Gas Code 2009 “Appliances installed in vented fireplaces and unvented firebox enclosures” Gas log setsFireplace insertsUnvented hearth appliances Shutoff valve installed at a manifold within 50’ of the appliance Vented fireplaces or free standing hearth appliances require a shutoff within 6’ of the appliance

Shutoff Valve Exceptions International Fuel Gas Code 2009: “Vented decorative appliances, room heaters and decorative appliances for installation in vented fireplaces” Vented gas hearth appliancesFireplaces Fireplace inserts Freestanding hearth appliances Vented gas log sets Unvented gas hearth appliances require shutoff within 6’ of the appliance

Sediment Traps Installed close to applianceIntercept solid debris to prevent blockageRequired by some appliance manufacturers– Prevent rusting and degradation of main burner

Appliance Connections International Fuel Gas Code Rigid or CSST (2006) = No length limit Semi-rigid =Maximum 6’Copper/aluminum tubing ANSI Z21.24 Listed Connectors In the same room as the appliance Length limited to 3’ • Extended to 6’ in 2009 • Protected from physical damage

Appliance Connections Additional IFGC requirements: Connectors to vented decorative appliances and room heaters can extend through walls, floors, partitions, ceilingsSemi rigid tubing and listed connectors canextend through protected appliance openings

Yellow Flame Combustion HVAC industry Yellow flame means inefficiencyHearth industryReduce primary air intake Use secondary air to achieve acceptable Combustion efficiency Flame aesthetics

Vented Gas Fireplace Installation Listed to ANSI Z21.50 Gas Fireplaces ANSI Z21.88 Gas Fireplace HeatersFloor Support and Protection:Most can be installed on combustible surface Carpet & vinyl usually not approved without metal or wood panel Appliance level and plumb, with adequate support Hearth extension may/may not be required

Vented Freestanding Appliance Floor protection May indicate installation on solid combustible floorMay indicate bottom heat shield required May require metal, wood panel, or listed padClearances Specified from front, sides, rear, corners Alcove may not be allowed

Gas Appliance Venting Systems Negative Pressure Category 1 (Natural draft hearth appliances)No condensateCategory 2 Capable of condensate Positive Pressure Category 3 No condensate Category 4 (Mechanical draft hi-efficiency hearth appliances) Capable of condensate

Conventional Vent SystemsDraft Hood Allows dilution air into venting systemProvides escape of flue gases in event of no draft, back draft, blockageReduces temperatures in ventReduces vent height affect – Stronger draft brings in more dilution, not combustion air

Conventional Vent Systems Type B Vent Factory-made, double wall metal pipeAir space between wallsClose clearance Help maintain draft and reduce condensation

1 18 Conventional Vent Systems Type B VentComponents not interchangeableunless allowed by manufacturer Hearth products use Round B vent Oval B 2x4 Oval B 2x6 NOT Type BW unless otherwise listed

Conventional Vent Systems Type B Vent Horizontal Run and RiseMinimum vertical height may be specifiedKeep horizontal run to minimum Rise at least ¼ inch per foot for vent or connector Maximum rise to run ratio 75% of vent height for single wall connector 100% for double wall B vent connector Manufacturer may require 50% maximum (2:1)

Conventional Vent Systems Type B Vent Termination with obstructions within 8’2’ higher than any portion of the building within 8’

Conventional Vent Systems Type B Vent Common VentingAppliances on different floors of building Only allowed for appliances in areasseparate from living space Appliances on same floor Not addressed or prohibited Appliance manufacturer may prohibit AHJ may prohibit

Conventional Vent Systems Type B Vent Chimney LinersRequired for gas fireplace inserts and freestanding appliances using masonry or factory-built chimneysListed liner systems Type B vent listed to UL 1777 Aluminum or stainless steel UL 1777 Rigid or flex

Conventional Vent Fireplace Insert Fireplace and chimney in good working orderSome require hearth extension protectionAlterations: variations by manufacturer Required removal of damper and grate Refractory, smoke shelf, baffles, screen, doors can be removed Insulation can NOT be removed

Conventional Vent Fireplace Insert Surround variationsGap between fireplace face and panel may be required for air circulation and coolingInsulation along top of insert may be required for mantel clearancesMay allow installation without panel if minimum gap with mesh maintained Air inlet grilles on factory-built fireplaces important consideration

Conventional Vent Condensing Appliance Plastic Pipe (PVC) Recognized in Fuel Gas Codes– Appliances must be listed for useHigh efficiency, Category IVResists corrosion from condensation Provides adequate heat protection Can be sealed for mechanical vent positive pressure

Direct Vent

Direct Vent Follow manufacturer instructions Venting ClearancesVent system is part of applianceAppliance manufacturer provides instructionsPermissible configurations are model specific

Direct Vent

Direct Vent

Direct Vent

Direct VentFireplace Inserts

Direct VentFireplace Inserts Air intake terminated above damper inside chimney Listing and instructionsMust be in instructionsMay require blocking of damper area

Direct Vent PVC Systems Provides outside combustion air Co-linearTwo separate PVC pipes Co-axialInner pipe expelling exhaustSpace between pipes providing combustion air Direct Vent Condensing Appliance

Mechanical Vent Systems Negative pressure (B-Vent or Direct Vent)Fan at flue collar or termination of vent Positive pressure (Direct Vent only) Fan before the firebox © Central Fireplace © Empire Comfort Systems

Unvented

Unvented ODS Pilot: Oxygen Depletion Shutdown Pilot flame engulfs tip of thermocouple Flame begins to lift offThermocouple begins to cool Unstable flame moves away from thermocouple Thermocouple stops generating sufficient mv to keep valve open Flow of gas stops Normal Operation 20.9% Oxygen Oxygen Level Dropping 19% Oxygen Safety System 18% Oxygen

Unvented NFGC & IFGC Combustion air requirementsUse of room restrictions IFGCMaximum input rating of 40,000 Btu/hr Not to be sole source of heating in house

Fuel Conversion Some appliances, including unvented, canNOT be field convertedOthers specify in instructions May required approved conversion kitLabel identifying fuel attached to control valve

QUESTIONS?THANK YOU FOR YOUR ATTENTION

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Fireplace Inspections - Description


Fireplace Inspections Made Easier 1901 N Moore St Arlington VA 22209 703 5248030 Hearth Patio amp Barbecue Education Foundation National Fireplace Institute Challenges ID: 765969 Download Presentation

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