There are so many sealers on the market today and it can be confusing to know which sealer is the correct choice for your limestone. Which one will work, which one won't, which sealer suits your situation and how they differ?
Sealing and Protecting LimestoneSealing prevents stain carrying moisture from being absorbed by your limestone.
All natural stone wall and floor tiles are absorbent to some degree. By pouring a teaspoon of water on an unsealed limestone tile you will see how quickly it absorbs and can then see how a potential stain can also be absorbed. This is because limestone tiles are porous, with small pin-holes and open fissures as part of its natural texture.
When used to cover flooring and walls, limestone tiles will require careful preparation, sealing and ongoing maintenance.
Unsealed limestone soaks up moisture fast
Limestone is a porous material, meaning that without a sealer dirt and stains can become easily trapped in the stone's pores, as well as the grout.Limestone benefits from being sealed in a number of ways:
- Stain prevention
- Prevent discolouration
- Limestone protection
- Surface enhancement
- Regular maintenance becomes easier
When limestone is sealed cleaning is simple – frequent sweeping and an occasional wash with a soft cloth and soap and water can help to keep your limestone in great condition for years to come. Limestone sealing with a quality stone sealant like Penetrating Sealer can increase the longevity of your stone and block out dangerous moisture, mould and calcification.
Once sealed, cleaning limestone is a breeze!
Choosing the Best Sealer
Impregnating sealers are suspended in a liquid carrier which is either water or solvent based. The sealer is absorbed into the small pin holes and open fissures just below the surface. Once absorbed the carrier evaporates, leaving the sealer behind which chemically reacts with the surface pores to form a breathable protective barrier.
An impregnating sealer protects your limestone surface and grout from absorbing stains while also resulting in cleaning and maintenance becoming much easier. Some sealers will last a few years while Australia's range of impregnating water based sealers last for up 15 years.
Solvent based sealers are usually only required in extreme cases, and generally not recommended. Water-based sealers utilise modern technologies such as nanotechnology and fluoro-polymer technology that render most old solvent based products obsolete.
Solvent based products often contain toxic fumes that can be dangerous for your health and when applied often require the area to be vacated for up to 48 hours. Solvents can cause damage to property such as skirting boards, doors, paint, and adjacent areas.
- To provide the best possible protection from oil and water-based stains; to maintain the look and slip resistance of your limestone and to prevent damaging moisture from being trapped within the stone, it is recommended to seal your limestone with a high quality, invisible, fully breathable impregnating sealer.
Generally impregnating sealers are effective for interior and exterior use, including use in wet areas such as kitchens, bathrooms, laundries, patios and around swimming pools.
Impregnating Sealer properties
- Penetrates into the limestone substrate and attaches its protection to the walls within the micro-pore structure. This allows for total vapour transmission through the stone.
- Does not change the colour or sheen of the stone.
- Does not need to be reapplied after each cleaning.
- Because the sealer does not remain on top of the surface, the sealer will not scratch or scuff. Without a surface coating to wear off, the sealer does not require re-application as frequently as topical sealers.
- A penetrating colour enhancing sealer is designed to enhance and enrich the natural look of limestone surfaces.
- Penetrating Colour Enhancer is an ideal sealer for limestone for two main reasons. Firstly, it is an impregnating sealer meaning it penetrates deep into the pores of the limestone to provide long lasting robust protection against ingrained dirt. Secondly, it contains colour intensifying properties which enhance the natural colours in the limestone. Sealing using a long-lasting penetrating sealer will not only help to prevent staining, but also extend the life of your limestone and ensure regular maintenance becomes much easier.
- Longer lifetime as the protection is contained within the substrate, and not simply on the surface
- Not affected by UV light (Great for use both outdoors and indoors)
- Allows the stone to 'breathe', retained moisture can escape
- Surface does not become slippery
- Improves the life expectancy of limestone
Impregnating penetrating sealants actually penetrate into the limestone substrate itself, soaking into the microscopic pin-holes and open fissures which make up its natural texture.
A clear impregnating sealer won't change the look or feel of your sealed limestone, won't affect the stone's ability to release vapour and will last much longer than film forming sealers.
Unsealed limestone surfaces are highly porous and susceptible to permanent staining from everyday spills. Sealing is important if you want to protect your limestone against unwanted staining and deterioration.
If you have a limestone tiled floor, you will know that it absorbs liquids and therefore any potential liquid carrying stains very quickly.
Topical sealers are used to form a protective gloss sheen on the surface of stone and masonry surfaces, whereas penetrating sealers penetrate the surface of the limestone and protect the walls of each individual pore within the limestone’s structure.
Some topical sealer drawbacks:
- Requires constant reapplication
- Needs to be completely removed before reapplication
- Stone can not breathe. Moisture is trapped in the stone
- Creates a shiny surface film that is easily scratched or scuffed
- Can make the surface slippery when wet
- Alters the colour of the limestone
Red wine, oil and grease in particular can result in damage that may be impossible to remove without the use of heavy resurfacing machinery. Although sealing limestone won't completely stop liquids from absorbing into it, it will give you time to wipe spills away before permanent damage occurs.
Cleaning and maintenance of limestone flooring can be more difficult when left unsealed as surface contaminants will quickly absorb into the porous limestone structure making them difficult to remove.
It is strongly recommended to apply a deep penetrating impregnating sealer to limestone floors that provide long lasting protection and stain resistance.
The best available penetrating sealer today is Australian made . produce non-solvent sealers that are easy to apply using a brush, roller or sprayer and will dry within a few hours. These deep penetrating limestone sealers are available in a dry, invisible finish or in a slightly wet, colour enhancing effect and have a lifetime of 10 or up to 15 years.
- Any surface to be sealed should be clean and looking just as you want it before it is sealed - it may be impossible to remove stains after sealing without once again having to strip away the sealer. Acidic cleaners should not be used on limestone as they will cause damage.
- Limestone must have no other coating such as wax or a topical sealer before it's sealed, so any such coating must be removed before sealing.
- Floor must be thoroughly dry before applying most sealers.
- Choose a quality long-lasting deep penetrating, impregnating sealer.
- Deeply clean your limestone prior to application (dust and debris will be trapped once sealed)
- Correct application and amount of required coats.
- Remember, with stone sealers you really do get what you pay for.
The number of coats required will depend upon the porosity of the limestone, a second or third coat of sealer can be required. Once sealed the tile will resist staining and provided the stain is wiped away within a reasonable length of time, there will be no evidence of any mark on the surface of the stone.
Limestone will vary in hardness and is always porous – if you apply a small amount of water to an unsealed limestone surface it will be absorbed in seconds. The porosity of limestone is also affected by the finish – for example a highly polished limestone is less porous in comparison to limestone with a honed (matte) finish.
Fluoro-chemical technology integrated into GOLD is the most advanced technology available, providing the ultimate long term protection against water and oil-based stains. The micro-molecular formula chemically reacts with the stone surface to create a bond that is stronger than any other conventional sealer.
provides durable protection against stains, superior oil and water repellency, no change to the natural surface appearance, is non-film forming, breathable, and easy to clean and maintain, preserving the beauty of your limestone.
Some Good Advice
Choose an experienced company with specialised equipment and expertise to correctly seal and maintain your limestone once installed.
It is important to keep your sealed limestone clean, wipe up spills quickly and clean periodically.
Professional cleaning will not only remove surface dirt but draws out dirt deep embedded within the pores of limestone.
Get in contact with a professional stone floor maintenance company with the equipment and knowledge to ensure you're valuable surfaces look just how you want them.
Tile Cleaners Australia and StoneMaster are members of the network of independent Accredited Applicators who have been fully trained in the proper application of limestone care products, offering a full service by thoroughly cleaning the limestone area to be treated, product application and providing after sales care.
- Tile Cleaners Australia is Australia's leading tile care provider of all tile & grout cleaning, tile sealing, tile stripping & sealing, tile regrouting, grout colour sealing, and minor tile repairs.
- StoneMaster provide a diagnostic approach to each unique situation, including a full analysis, selection of the best-required method of restoration and follow up maintenance procedures always ensuring outstanding results.
Ensuring your limestone is thoroughly cleaned before sealing is important as you may seal in old stains or dust and debris embedded in the stone, resulting in the sealer needing to be stripped and resealed.Applying a sealer that is not suitable or of sufficient quality will result in limestone surfaces you aren't completely satisfied with.