Doing it yourself? Visit our "How to install twin wall flue" page.
This is a twin wall clip-together chimney part used to build a new chimney. Twin wall clip-together chimney can be as close as 5-7cm to combustible materials (so is also useful for adding atop a stove to bypass a wooden beam).
Slide through the wall and cut to length as required. Add mortar around outside of it or Rockwool insulation. Make sure it is Rockwool (some other brands not fireproof).
Diameter of 5" sleeve: 9"
Diameter of 6" sleeve: 10"
You might decide to use a metal sleeve through the wall. Any gaps around the sleeve can be filled with mortar. Note that most fitters do not use a sleeve but just push the pipe through and fill the gap with a mortar/vermiculite mix even though Building regulations state that there should be a sleeve "if the pipe is likely, through heat expansion, to damage the building or the pipe".
I have used a sleeve on some jobs and not on other jobs. If not using a shield I fill the gap between the pipe and the building with Rockwool insulation (available from many merchants but it MUST be Rockwool brand as other brands are not fireproof). My thoughts here are that, as there is no expansion issue, no sleeve is required.
Stove Fitter's Warehouse offers a FREE Twin Wall Design Service.
Duraflue Twin Wall was launched to the market during 2014 and, due to its high quality and innovative design, is already a favourite amongst professional stove fitters. Brackets are strong whereas other brands may be spindly and quality is premium. Do it once - do it good.
Top tip: No fire cement or glue of any kind is used when connecting twin wall pipe to twin wall pipe - it is just push-fit (with a locking band for added security). When to use fire cement on flue joints? Use the SEARCH function and type "sealing flue joints".