The maximum angle for a flue (or chimney pipe offset) depends on your appliance type and local building codes, but for solid-fuel appliances (like wood or pellet stoves) in the US, the maximum allowed angle is 30 degrees from the vertical. In Canada and the UK, the maximum allowed angle is 45 degrees.
Yes, 90-degree bends can be fitted with our condensing boilers if the correct allowance is made on the maximum flue length. We recommend a 1.3 metre reduction for each 90-degree bend and a 0.9 metre reduction for each 45-degree bend.
NFPA 211 (US regulations) states that chimneys can be offset 15° or 30° while CSA B365 (Canadian regulations) states it can be offset at a 30° to 45° angle. Proper clearances must be maintained and the correct materials must be used.
No more than four bends are permitted in the entire length of the chimney. Each bend must not exceed 45 degrees from the vertical, though a 90-degree factory-made bend or tee counts as two 45-degree bends.
If bends are unavoidable, then there must be no more than four bends in the length of the chimney. A bend should be no more than 45 degrees from the vertical, with the exception that 90-degree factory-made bends or tees may be treated as two 45-degree bends.
Yes, you can use a 90-degree elbow in a plumbing vent pipe, but it should be used sparingly and, where possible, replaced with two 45-degree elbows to improve airflow and reduce the risk of blockages. Vents can accommodate sharp 90-degree turns, but they must be properly sloped to prevent issues with condensation or debris.
The 3-2-10 rule is a vital building and fire safety standard used to determine the correct height of a chimney. It ensures proper draft (so smoke and toxic gases exit the home rather than back-drafting) and lowers the risk of roof fires.
The "7 Times Rule" for chimneys dictates that the cross-sectional area of a masonry chimney flue cannot exceed seven times the area of the appliance’s vent connector (draft hood outlet) to ensure proper drafting and prevent acidic condensation. If the chimney is too large, it must be relined to prevent damage from cooling gases.
Additionally, in the early 1980's, tests were conducted to discover which kind of wood created the most creosote in a regular “open” fireplace. The results were surprising. Contrary to popular opinion, the hardwood's, like oak and poplar, created more creosote than the softwoods, like tamarack and pine.
The National Electrical Code (NEC) 360-degree rule states that you can have a maximum of 360∘360 raised to the composed with power360∘ of total bends—the equivalent of four quarter bends—in a single conduit run between two pull points (e.g., junction boxes or conduit bodies). This prevents wire-pulling damage and insulation stress.
Unfortunately, a larger diameter flue doesn't always cure a draft problem. Many times, "increase diameter - decrease velocity " only slows down the speed of the exhaust gases. A 6" flue should be plenty adequate for that size stove.......
Yes, mice absolutely can and do come down chimneys, utilizing them as warm, sheltered, and vertical pathways to enter homes. Mice are excellent climbers that can scale the exterior brickwork, enter through gaps or cracks, and move down the flue into the fireplace or attic.
While you can physically reduce an 8-inch stove pipe to 6 inches using a standard reducer, it is not recommended and is often against code or manufacturer guidelines unless explicitly permitted. The manufacturer sized the flue at 8 inches to ensure proper draft—restricting it can cause smoke to roll back into the room, lead to dangerous creosote buildup, and reduce stove efficiency.
The Ideal 90 degree elbow bend has been primarily designed for use to manoeuvre a flue run around obstacles or to create a raised horizontal flue run, used in areas where space is minimal.
Yes, a fireplace flue can be angled. Offsets and bends are commonly used to navigate around obstacles like rafters, joists, or to center the chimney stack. However, it must adhere strictly to local building codes regarding maximum angles and required clearances.
As excessive bends and horizontal runs can accumulate soot with the risk of blockage, the flue pipe should be kept as vertical as possible and the angle of bends should be no more than 45° from the vertical.
The worst firewood to burn falls into two categories: toxic and highly inefficient. You should never burn wood that produces dangerous chemical fumes or excessive smoke, nor wood that burns too quickly or spits hazardous sparks.
Hot fires kill creosote.
If you keep your chimney temperature above 250º F, you are far less likely to have problematic amounts of creosote accumulate between yearly cleanings.
Creosote is restricted or banned across residential and consumer markets due to its classification as a probable carcinogen and its high toxicity to the environment.
Can we use a 4-inch pipe for a chimney? A 4-inch pipe is suitable for smaller systems such as kitchen exhausts, but it may not be appropriate for larger fireplaces or wood-burning stoves.
Some authorities recommend cleaning the chimney after every third cord of wood is burned and most recommend at least once a year. Any time you observe excessive soot and creosote, the chimney should be cleaned.
Yes, mice can absolutely come down your chimney. Because mice are agile climbers and can squeeze through openings as small as a dime, they easily scale the outside of a chimney and slip inside seeking warmth and nesting sites.
Professional roofers possess extensive experience with chimney-related repairs that directly impact roof integrity and weatherproofing systems. Their expertise covers external chimney components including flashing replacement, crown repairs, and addressing problematic areas where the chimney penetrates the roofline.
Never step down in size anywhere on the flue route as this will cause a bottleneck and the smoke may back up, eventually filling from the stove (and it's illegal). For example, if a stove has a 6" collar it cannot have a lesser diamter flue size.