Chimney Damp? Don’t let it ruin your Christmas

31st Oct 18 | Back to blog

Chimneys suffering from damp are a common thing, whether in use or not, and especially being so open to the elements. Damp can occur because of the moisture and sulfates that combine to form weak acids that attack brickwork, lime and mortar joints. It can also be caused when a chimney is sealed and the moisture becomes trapped within. More common however is typical British rain, condensation or salts contaminating.

chimneyIf the chimney pot is uncapped, this means rain can enter down the flue, through defective lead flashing’s or through the actual chimney wall its self.

Burning fuel in a chimney can often lead to condensation issues as the fuel burnt produces a large quantity of water vapor.

Salt contamination in the plaster of a wall can also cause damp. This is more common in older chimneys and it can be the result of coal previously being burnt in the fireplace. Coal contains salt minerals like nitrates, chlorides and sulfates that can migrate from the brickwork into the wall plaster. These damp patches can often worsen when the weather does.

Check out your chimney

There are several ways to identify whether your chimney is suffering from damp. Here are a few ways:

  1. A simple and common thing to firstly start of with is to check your gutters. Especially through the winter months, leaves and other debris tend to gather in the gutters, forcing water to go where it shouldn’t. If the wall in which the water is running down has any cracks or damage this well cause damage to the chimney breast and create damp.
  2. Check the lead flashing, tiles and loft space to see if there is any damage. Again water coming through will have disastrous effects on the chimney. chimney crack - mortar
  3. Has the chimney had a previous damp proof course installed? Some older properties were built without one, which again may be contributing to the damage.
  4. Check any mortar around the chimney, if cracked this again will allow water to penetrate.

For more advice on any of the above contact us today to request your free survey.


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