In terms of maintenance, a limestone fireplace can be a bit more demanding than other natural stone fireplaces. This is because limestone is slightly softer and marginally porous than more sturdy natural stones like granite. Thus, if you own or are planning to buy a limestone fireplace, read on to learn some basic maintenance tips.
1. Take Cleaning Precautions
Regular cleaning is essential for limestone, but you should use carefully chosen supplies since this stone is vulnerable to getting scratched. Thus, beware of the following:
Wax/Spray Polishes—These can cause discoloration of limestone, causing hard-to-remove stains.
Specially-Formulated Kitchen/Bathroom Cleaning Solutions—even mildly-potent chemical agents like bleach can chemically react with the limestone and discolor it.
Paper Towels—these can scratch the limestone surface. Chances of this happening increase exponentially if your fireplace has unpolished or unfinished limestone.
Steel Wool—scraping of any kind is seriously inadvisable. Even mild scrubbing tools like steel wool can ruin the stone's surface. For the more stubborn stains, used soft-bristled toothbrushes are recommended.
2. Remove Dust/Debris with Care
Always clean the limestone fireplace before cleaning it with any solution. Removing the dust/debris before wetting the surface is critical as these particles can get embedded into the limestone surface upon cleaning with fluids. Vacuuming limestone surfaces isn't the wisest option since the vacuum attachments can be quite hard and may scratch the limestone surface. Use a microfiber cloth to loosen the grime and remove the dust. If microfiber cloth is not available, use any kind of dry, cotton-based cloth.
3. Comprehensively Clean Limestone Fireplace
For more comprehensive cleaning, prepare a cleaning solution of lukewarm water and a few drops of mild/neutral dishwasher soap. Prepare this solution in bucket. Dip a sponge into this solution and repeatedly wipe the limestone surface with this. Rinse the limestone surface with clean water and wipe it with a microfiber cloth. To properly remove the moisture, wipe the limestone surfaces with a terrycloth towel.
4. Avoid Possible Staining
Don’t keep flower vases containing water over limestone surfaces as moisture can react along the point of contact between the limestone and base of the vase, inducing permanent ring-like marks.
You need to be very careful about handling fireplace essentials like wood or coal when using limestone fireplaces as the debris from such sources can get impacted upon the limestone surface.
5. Remove Fresh Stains with Poultice
Poultices can be used for removing fresh stains on limestone fireplace surfaces. A safe/inert poultice that doesn’t react with the limestone and can absorb a large quantity of the staining compounds is prepared from baking soda. Mix a few pinches of baking soda and distilled water and use this mix for wetting the poultice. Place the wet poultice over the stain and leave it overnight.
6. Apply Periodic Limestone Sealer Treatment
Fireplace surfaces need a periodic sealing to ensure that the soot or smoke from the fireplace does not get impacted upon them. Softer and more porous natural stones like limestone need a stronger sealer. You can also opt for sealers with a shiny luster. If soot seems to be a major issue, it is better to choose an impregnating sealer. This is particularly useful for limestone as such sealers can penetrate deeper and form a protective layering that will not allow debris, including soot, to get entrenched. For similar reasons, sealers with a silicone base are a better option. If there is a limestone mantel, you can use a topical sealer. This less penetrative sealer is used for mantels since mantel surfaces are further away from the smoke/soot.