The rain cannot get in but it is not sealed air tight which does allow any inside moisture to slowly get out.
Capping off a disused chimney.
Capping a chimney has it s benefits if your no longer going to use it the main benefit is the thermal efficiency it will give your home.
Another excellent type of chimney capper when capping off disused chimneys are the metal versions with inbuilt fixing straps and a large stainless steel jubilee clip.
If bits of brick have crumbled inside or if there is significant decay consider calling a.
Climb onto your roof to inspect the chimney.
Then measure across your flues to find the widest point.
It will also stop any birds or insects nesting inside the chimney stack or becoming stuck and dying such a shame.
You may need to use a screwdriver to loosen screws holding it in place.
Remove the cap on the chimney.
Usually unused chimneys are capped off with a bent sheet metal covering and perhaps a wire strap or weight on the top.
Take measurements for the length width and height of the chimney s flues.
Extend the tape measure to find the total combined length of all the flues.
The bottom is even easier.
How to close an unused chimney.
The key to capping the top of the chimney is to install a barrier that will be moisture and tamper resistant and will not be affected by environmental factors such as snow wind and sunlight.
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.
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.
Measure all sides of the.
Again mostly available in terracotta but sometimes in buff there are really two typical versions of this a plain cap which can be adjusted in height slightly on the pot to give varying amounts of ventilation depending on your preference.
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.