Place the end of your tape measure against the side of the flue which is the clay or metal tube coming out from the top of your chimney.
Capping off an unused chimney.
Remove the cap on the chimney.
Measure all sides of the.
The rain cannot get in but it is not sealed air tight which does allow any inside moisture to slowly get out.
Extend the tape measure to find the total combined length of all the flues.
Capping a chimney off with a slab.
The bottom is even easier.
Http www fixmyroof co uk videos and guides chimneys chimney capping in this video i show 3 different ways to cap off a disused chimney that does not alter.
If bits of brick have crumbled inside or if there is significant decay consider calling a.
Usually unused chimneys are capped off with a bent sheet metal covering and perhaps a wire strap or weight on the top.
Capping a chimney off with a slab is well not may favorite at all.
You may need to use a screwdriver to loosen screws holding it in place.
One old and virtually free method of capping off or sealing a chimney that is generally no longer used is to make a lead cap.
Take measurements for the length width and height of the chimney s flues.
How to close an unused chimney.
Simply cut a tight fitting plug out of foam insulation and block the hole on the bottom.
Other helpful maintenance.
These can simply be made out of a scrap or an offcut of lead beaten into the correct shape and bonded to the top of most chimney pots to effectively seal it and make it waterproof.
Why should unused chimneys be capped.
Then measure across your flues to find the widest point.
If you decide to cap your chimney off yourself please make sure you use the correct ladder safety.
Capping the flue is one of the best ways to close up the top of the chimney as it will still allow air to get in and out preventing condensation from building up.