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.
Capping off an unused chimney.
Take measurements for the length width and height of the chimney s flues.
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.
Extend the tape measure to find the total combined length of all the flues.
You may need to use a screwdriver to loosen screws holding it in place.
The rain cannot get in but it is not sealed air tight which does allow any inside moisture to slowly get out.
If you are only talking a few feet of redundant flue then you ll probably be ok with fully capping after reducing the height with a single vent left in the blocked up fireplace.
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.
Remove the cap on the chimney.
Why should unused chimneys be capped.
Other helpful maintenance.
Capping a chimney off with a slab.
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.
Insulating the bottom of the chimney once you ve capped the top of the chimney you will need to insulate the bottom of it.
How to close an unused chimney.
Measure all sides of the.
The bottom is even easier.
Then measure across your flues to find the widest point.
Capping a chimney off with a slab is well not may favorite at all.
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.
Simply cut a tight fitting plug out of foam insulation and block the hole on the bottom.