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Orillia WETT Inspections

Orillia Wett Inspections for all your wood burning insurance requirements.

Call the Orillia Home Inspector to book your WET Inspection. 705-795-8255

inspect your wood burning appliance by certified inspectorThe Scope of a Level 2 WETT Inspection is termed as “Accessible” , which includes the following: 1) A Level 1 inspection, and
(2) an inspection of all “accessible” components of the system for clearance to combustibles and for obstructions or deposits, and
(3) an evaluation of the construction, sizing, condition and suitability of “accessible” components of the system.

The purpose of a the Level 2 inspection is to : 1) When a Level 1 inspection is deemed insufficient because of a detected or suspected compliance issue or hazard, or
(2) when verification of the suitability and integrity of the system components is required, or
(3) after an operating malfunction or external event that may have caused damage to the system, or
(4) if the system experiences combustion spillage events, or
(5) when an appliance is replaced, or
(6) when a major system component is replaced or requires significant repair.

The Process of performing a Level 1 WETT inspection includes:
(1) A basic visual inspection by a WETT certified SITE inspector; performed without a ladder or specialized tools.
(2) A report using WETT##Q##s recommended inspection checklist(s) or similar checklist(s), for the type of system being inspected.

The chimney is usually the most difficult part of the system to inspect properly. Chimneys which run up through the house are often inaccessible at critical points, such as ceiling and attic penetrations. In some cases, even though you can see sections of the chimney, they cannot be reached with a tape measure to confirm their clearance to combustible building materials. Flue liners are subject to cracking inside masonry chimneys, or buckling and corrosion in the case of metal chimneys. It is difficult to inspect a chimney” title=”View all articles about wett here”>” title=”View all articles about liner here”>liner unless it has just been cleaned.

A certified technician or chimney sweep will prepare a detailed, written report and have the homeowner sign it. He or she will make sure the homeowner understands the report, especially those areas where problems are found.

Many insurance companies in Canada are requiring Wood Energy Technology Transfer (WETT) inspections, an inspection of wood burning appliances, before issuing insurance. A WETT-inspector will visually inspect the safety of any wood-burning appliances. Call the Barrie Home inspector for all your wood burning inspection requirements.

The Orillia Home Inspector is WETT Certified and has been providing WETT inspection services since 2005. Let the Orillia Home inspectors expertise and training protect your home and investment. Whether purchasing a new home with a fireplace or wood stove or installing a new wood burning appliance call the Orillia Home Inspector.

WETT Certified Appliances

A Certified Appliance is a unit which has been tested by a “recognized testing facility” (Underwriters Laboratories of Canada,  Underwriters Laboratories, Warnek Horsey and CSA) and typically have a plate or sticker usually located on rear of appliance listing requirements of installation.  When your wood burning appliance bears one of these labels it means the Products bearing the Warnock Hersey (WH-ETL) Mark or ULC etc, and  indicate compliance to relevant building codes, association criteria, and product safety and performance standards.

Insurance is part of wood heat safety, and making your system safer ensures you the best possible premium for your insurance. Call your insurance representative to review your coverage and inform him or her when you make any changes. This includes adding or changing a wood stove, modifying a chimney – anything that may influence the safety of your system. Your insurance representative will want to know if your unit is certified by Underwriters’ Laboratories of Canada (ULC) or the Canadian Standard Association (CSA) and may refuse to insure your home if the stove is not certified. He or she will also want to know if your unit was installed by a professional and if the clearances are up to the latest Building Code and Fire Code, including a proper floor pad, venting system and so forth.

Wood burning appliances fall into two distinct categories. Uncertified appliances are typically older units that have never under gone the rigorous testing required to obtain a Certification by a testing laboratory.  Certified appliances have been tested by one of the registered laboratories, i.e. CSA, ULC, OTL or Warnock-Hersey, and have passed all requirements.

I actually attended a “woodstove certification testing” in Toronto and was amazed at the detail of testing.   First, it is the manufactures responsibility to determine the safe distances Certification Label - Alliston WETT Inspectionsrequired to combustible construction,  that information is part of the installation instructions.   ULC in this case, set the stove up in accordance with the installation instructions and then placed “heat sensors” around, below and above the wood stove.   The wood stove was then fired up and ran for an hour or two as measurements were taken from all the different sensors.  If any sensor indicated heat above the testing limits, the unit would fail.   Most manufactures tend to err on the side of safety when specifying distances to combustibles as the cost of one test was over $15,000 dollars ten years ago.

If you are purchasing a home equipped with a wood burning device, it is very important to add a clause to your offer that unit pass a WETT inspection to determine whether the unit is installed correctly and is safe to use.  Many older units are very unsafe and even chimney’s that were allowed 15 to 20 years ago may not be allowed today. On one such visit we found an uncertified appliance located within 4 inches of an unshielded combustible wall.  A type chimney’s were used in past years and can still be used today as long as original configuration is left intact.  If you were to upgrade or replace your wood stove you would no longer be able to use A type chimney and replacement would be required.

Every part of your wood stove or wood burning appliance has to be installed in accordance with the manufactures instructions.  If you install a stainless steel chimney all parts used have to be approved by manufacturer.  If in doubt call the manufacture or their local representative to find out what products can be used in conjunction with theirs.

Check with your insurance company prior to installing any wood burning appliance.  Some insurance companies will not insure an installation unless installed by a WETT Certified Installer.   Even if  they do accept your installation they may require a level 2 WETT Inspection which could significantly reduce money saved by doing installation yourself.

If you are buying a new home and the fireplace or wood stove has been used on a regular basis then it is recommended that you hire a WETT Certified Chimney sweep to clean your chimney and provide you with a WETT Inspection.   The heavy build up of soot and creosote would prevent some doing a Site Basic inspection from viewing any cracks in flue pipes etc due to buildup in chimney.   So protect your home and your family by having a WETT Certified Inspection of your wood burning appliance.

Flue Pipe Installation

Flue Pipe Installation.

The rules provided here are based on the CSA installation code used in Canada.

For installation requirements call the Barrie WETT Inspector at 705-795-8255



  1. Barrie Wett Inspections - Flue Pipe AssemblyMaximum overall length of straight pipe: 3 m (10 ft.)
  2. The assembly should be as short and direct as possible between the stove and chimney. The use of two 45 degree elbows is often preferable to a single 90 degree elbow because less turbulence is created in the exhaust flow and they result in less horizontal run.
  3. Maximum number of 90-degree elbows: 2. Maximum unsupported horizontal length: 1 m (3 feet).
  4. Galvanized flue pipes must not be used because the coatings vaporize at high temperatures and release dangerous gases. Use black painted flue pipes.
  5. 6-, 7-, and 8-inch diameter flue pipes must be at least 24 gauge in thickness.
  6. Flue pipe joints should overlap 30 mm (1 1/4 in.)
  7. Each joint in the assembly must be fastened with at least three screws.
  8. The assembly must have allowance for expansion: elbows in assemblies allow for expansion; straight assemblies should include an inspection wrap with one end unfastened, or a telescopic section.
  9. Minimum upward slope towards the chimney: 20 mm/m (1/4 in/ft.).
  10. One end of the assembly must be securely fastened to the flue collar with 3 sheet metal screws and the other end securely fastened to the chimney.
  11. There must be provision for cleaning of the pipes, either through a clean out or by removal of the pipe assembly. Removal of the assembly should not require that the stove be moved.
  12. The crimped ends (male) of the sections must be oriented towards the appliance so that falling dust and condensation stay inside the pipe.
  13. A flue pipe must never pass through a combustible floor or ceiling or through an attic, roof space, closet or concealed space.
  14. Minimum clearance from combustible material: 450 mm (18 in.). The minimum clearance may be reduced by 50 percent to 225 mm (9 in.) if suitable shielding is installed either on the pipe or on the combustible surface.

Single Wall Pipe AssemblyA straight up single wall flue pipe assembly.The ideal flue pipe assembly is one that rises straight up from the appliance flue collar and directly into the chimney with no elbows. The system at the right is single wall pipe with an inspection wrap (pipe coupler) to allow it to be assembled and disassembled without moving the stove.

A straight flue pipe assembly offers the least restriction to gas flow and results in stronger draft. Straight assemblies also need less maintenance because there are no corners for creosote deposits to accumulate.

A perfectly straight flue pipe assembly is another good reason to install chimneys up through the warm space of the house, instead of out and up and outside wall.

Certified double-wall flue pipe systems are also available. These systems are tested to determine the minimum clearance at which they can be installed. The clearance information is found on the labels attached to the pipe and in the manufacturer’s installation instructions. The rules for their installation may differ from the rules for single-wall flue pipes.

Double Wall Flue Pipe AssemblyA straight up double wall flue pipe assembly. This one is the sealed type.The minimum installation clearances for certified double-wall flue pipes are much less than those for single-wall pipes. Also, the maximum length of a double-wall flue pipe assembly may be greater than is permitted for a single-wall pipe.

There are two general types of double-wall flue pipes: sealed and vented. A sealed double-wall flue pipe is effective at retaining the heat in the flue gases because the air space between the inner liner and outer shell acts as an insulator.

A sealed double-wall pipe is a good choice to maximize draft and minimize creosote deposits. Use sealed double-wall pipes if the assembly must be long or if the appliance is expected to produce low flue gas temperatures. The system to the left uses a sealed double wall telescopic length between the stove and chimney.

A vented double-wall pipe allows cooling air to pass between the inner and outer layers. Where the flue pipe assembly is short and straight, a vented double-wall pipe can be acceptable. However, vented pipe is not a good choice for longer flue pipe assemblies or for appliances that are expected to produce low flue gas temperatures.


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