About Limestone
Limestone is a sedimentary soft rock that consists of mainly calcium carbonate. In its pure state it is white but it may be coloured by other materials. Limestone is formed either from accumulation of animal shells in a calcium carbonate cementing matrix or by crystallization from solution.
Sealing Limestone
All limestone is highly porous - a tablespoon of water on a limestone surface will be absorbed in seconds, although it does vary in porosity from piece to piece. Porosity is also affected by its finish - highly polished limestone is a little harder to penetrate than limestone with a honed (matt) finish.
Due to its high porosity it is particularly important for limestone to be sealed with a high quality impregnating sealer which will not affect its slip resistance or look.Limestone is used both outdoors and indoors, and Dry-Treat's premium impregnating sealers will seal limestone equally well in either.
Protection from Acid Etching
It is very difficult to seal limestone against acid attack.
Limestone and other calcite based stone such as marble and travertine are prone to acid etching. Limestone is immediately 'etched' (eaten / corroded) by any acidic material on contact - including lemon juice, cola, wine and champagne. For this reason the honed (matt) look is popular, as it doesn't show the matt etch marks as much as polished limestone. In any case, acidic substances should be cleaned up as soon as possible, and limestone should not be used outdoors in areas where there is acid rain.
Which Dry-Treat Sealer is Best for my Limestone?
STAIN-PROOF Original™
Permanent, invisible, fully breathable impregnating sealer for water and salt, PLUS premium oil stain protection. Eligible for 15 year performance warranty when your limestone is sealed by an Accredited Applicator. Click here for more details.
DRY-TREAT 40SK™
Permanent, invisible, fully breathable impregnating sealer for water and salt protection, plus surface consolidation. particularly popular for sealing limestone in a saltwater environment - such as around a salt water swimming pool. Click here for more details.
ENHANCE-PLUS™
For colour enrichment PLUS water based stain protection.5 year performance warranty when sealing is performed by an Accredited Applicator. Click here for more details.
Plus: STAIN-PROOF Original™ (1 coat) for additional oil protection at least 24 hours after ENHANCE-PLUS™.
Pre-sealing Preparation
1) 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. Acidic cleaners should not be used on limestone.
2) Check with the store your limestone came from that the surface has no other coating such as wax or a topical sealer, and ensure any such coating is removed before sealing. STAIN-PROOF™ and most Dry-Treat impregnators will penetrate other impregnating sealers, but not topical sealers.
3) Ensure the material is thoroughly dry before applying any Dry-Treat sealer.
Dry-Treat X-DUTY Cleaner™ is a highly effective, heavy duty cleaner which is safe to use on most types of porous surface. X-DUTY Cleaner ™is also an effective wax remover. Click here for more details.
Bleach diluted with water (1 part bleach to one part water) may also be used for stubborn stains. Apply the diluted bleach to the stained area, let it sit for 1-2 minutes, agitate with brush or cloth and then rinse well with clean water.
PLEASE NOTE:
1) Always test any cleaning chemical or sealer on a small, inconspicuous area of the surface 24 hours before doing the project, to check that it will produce the desired result.
2) Always ensure the surface is completely dry before proceeding with sealing.
