Chimney masonry stack how to#
Chimney masonry stack code#

CHIMNEY HEIGHT & CLEARANCE CODE for details about the required height of a chimney above the building roof.

In earthquake and high wind areas additional chimney support may be required by local codes, including reinforcement within the masonry structure of the chimney itself.Ĭontinue reading at CHIMNEY LEANING, SEPARATION, MOVEMENT or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX. In our photo (above) the loose wobbly brick chimney was not supported at the roof and was not connected to the building - hence it moved easily and was in danger of collapse.Ĭhimneys built on the exterior of a building need lateral support every twelve feet of height as they pass up the building wall - shown in Carson Dunlop Associates sketch. Lateral Support Requirements for Masonry Chimneys

Chimney masonry stack how to#

An expert was needed to decide how to make this one safe.Ĭhimney bracing sketches below are provided courtesy of Carson Dunlop Associates. If the flue were intact and there was no other damage it might be possible to secure the chimney against movement. A good wind could blow this chimney down. Watch out: don't try this at home and certainly not when there are people below, or when the flue is in use or probably any other time. Pushing gently on a tall flue like this should not produce easy movement. When we leaned on it a bit while climbing onto this roof. The chimney in our photo (above left) rocked and nearly fell over Loose wobbly masonry chimneys may be missing both lateral support (ties to the building wall) and rooftop support (Carson Dunlop's sketch, below right). When these supports are missing, even a chimney set on a solid foundation may tip, wobble, or separate from the building it serves. Lateral support may be required to tie a chimney to the building structure. Bracing Requirements for Masonry Chimneysīracing may be required for chimneys that extend high above the roof line. We also provide an ARTICLE INDEX for this topic, or you can try the page top or bottom SEARCH BOX as a quick way to find information you need. How do we strengthen tall or wobbly masonry chimneys? This article describes when and how support is added to tall masonry flues along the building exterior wall or above the roof-line. We have no relationship with advertisers, products, or services discussed at this website. If you would like us to design your (non truncated) flue system then please go to the flue design service section of this site.InspectAPedia tolerates no conflicts of interest. If you would like us to design your truncated flue system then please give us a few measurements and details on our truncated flue design form. Fixing and flashing components are available to make this easy for a wide variety of roof types.įor further technical advice, chimney and flue design and consultancy please contact us on 08 The anchor plate lets you join the chimney liner to AKW twin wall flue pipe, and also takes the weight of the twin wall flue pipe.įrom the anchor plate up AKW twin wall flue pipe is used to penetrate the roof and to rise up to the required height. The top of the stack should be made good and a flat surface provided for installing the anchor plate. The solution is to line and insulate the stack to the top with a register plate at the bottom (as normal) and a fixing clamp installed into the masonry chimney to take the weight. You would normally line and insulate the chimney with a flexible chimney liner right to the top of the stack, but of course the stack now terminates in the loft. Whatever the reason for having a truncated stack it means that installing a stove is not quite as simple as it might be. The roof might have been replaced and it might have been decided that the chimney stack would not be needed.

There may been many reasons why the chimney was truncated, for example the stack may have been in very bad repair and not in use so it might have been cheaper and quicker to simply remove the portion of the stack above the roof. It is quite common to find that an existing masonry chimney stack has been truncated so that it does not penetrate the roof. Roof penetration Lining a truncated chimney and using twin wall flue for the Help & Advice > Installation & Regs > Chimney Installation > Lining a truncated chimney and using twin wall flue for the