An Information Guide To Maintaining Limestone Fireplaces

Limestone is very durable and is an extremely good choice for a fireplace!

However, limestone is also rather soft and relatively porous, so it does require care from the householder to prevent stains and grubby marks spoiling the surface – especially for new limestone fireplaces!

A few important points for first time buyers!

Your limestone fireplace should be chemically sealed with a good quality sealant. The better sealants do not change the colour of the limestone to any degree, but prevent easy penetration of possible stains from getting into the stone. Your fireplace supplier should either seal your fireplace for you, (probably at extra cost) or provide a tin of liquid sealant for you to paint over the surface yourself (also probably at extra cost). These sealants cost around £20 or more per tin, so if you see one for much less, don’t use it, as it may not be good enough, and could darken your limestone fireplace colour!

If you have a limestone hearth, this should be sealed twice. Leave the first coat to completely dry and then add the second. Make sure you do not apply too much sealer, as this could cause a change to the surface if soaked!

You may have to repeat the complete sealing process after about six months or a year, especially if the fireplace is for solid fuel. After that, your limestone fireplace will probably not require any further chemical sealing.

Cleaning Limestone Fireplaces

The best way to clean off a grubby mark from your limestone fireplace is simply to use a clean cotton cloth dampened with very dilute washing up liquid. Do not soak the stone though!

If you have coffee or wine etc, spill onto your limestone fireplace surface don’t panic, just clean it off thoroughly with a dampened cloth and everything should be fine.

A number of things not to do:

  1. Never use wax or spray polishes on a limestone fireplace, as these products can darken the surface of the limestone and create patches.
  2. Never use kitchen or bathroom cleaners, as they could react with the limestone surface.
  3. Never allow cigarettes to be placed on the stone surface, the heat could cause a brown scar.
  4. Never stand vases with flowers directly on the limestone surface, as this could cause a permanent ring mark!
  5. Never stand red wine, tea or coffee etc, directly on your limestone fireplace -stains and ring marks could result!
  6. Never stand coal or logs directly on the fireplace surface – damage and stains may result!
  7. Never plaster down to, or on to a limestone fireplace – the stone will take up colour from the plaster.

The above list of “don’t do’s” for limestone, can also be found here on the Money Saving Expert Forum, as I posted it there in the first instance, prior to writing this article!

Real Fires, Limestone Fireplaces and Cracking caused by heat!It is important to be aware that limestone can crack from the heat of a real fire!

A limestone hearth section, which is close to a real fire can become extremely hot, whilst the edges of the hearth can stay relatively cool. Given the right length of time, a limestone hearth, is virtually guaranteed to crack!

There are things you can do to overcome this type of problem… One of the most common, is to have a limestone hearth cut / sectioned and re-sealed for real fire use!

To achieve this, the hearth is cut into a number of sections, and then reassembled with joins… These joins act as expansion joints. In addition to this, the hearth is normally then backed by high temperature cement, for extra protection!

The joints in the hearth should now prevent the stress spreading across the surface and therefore prevent the hearth from cracking – a heat plate could also be used, to assist in protecting the limestone from the heat and scratches.