Preparation

Most hard surface building materials are porous and can easily absorb foreign liquids. To avoid such issues a sealer can be applied. Before applying any sealer it is absolutely essential that the surface be prepared thoroughly. As there is always a trigger mechanism for coating failures our below guide will aid in eliminating such scenarios. Remember…A Coating Is Only As Good As The Floor Prep!

Film Forming Preparation

PRE APPLICATION TESTING

 

1. CONTAMINANTS


Contaminants such as oil or grease stains must be removed prior to any application.
Such techniques determined by applicators include degreasers, alkaline cleaners, hot water pressure washing and stiff broom agitation to name just a few.

 

2. HYDRATION – (2 Minute Water Test)


Concrete coatings and natural stone sealers are best applied to porous substrates. To test porosity apply a few drops of water to surface for a period of 2 minutes. After such time dab up using absorbent towelling. If surface darkens slightly or there is evidence of absorption this suggests surface is porous.

It is advisable to do a number of tests across the surface to ensure results are consistent.

 

3. MOISTURE – (Plastic Sheet Test)


Problems with floor coverings, such as bubbles, blisters, and de-lamination can occur when an impermeable floor coating or sealer traps excess moisture remaining in the slab.
Application of most coatings requires substrate to be free of dampness, discoloration, or damp odors. Water based sealers have some tolerance to moisture.
Determining if moisture is present is vital in preventing disappointment from a coating failure.
The most accurate method in determining moisture levels is by utilising a moisture meter.
If not feasible then the simple Plastic Sheet Method may be used.
Plastic Sheet Method
You can do this simply by cutting a piece of plastic sheeting and taping down the perimeter with duct tape to the surface of your floor.
After letting it sit for 24 hours, peel it up and look for any condensation on the underside of the plastic. Equally look for dark spots on the surface of the concrete. Water on the plastic or a dark spot on the concrete is created from moisture.
If none exists, this suggests excess moisture is not present.
If you do have some moisture then application of a coating should be delayed until re-testing indicates no moisture.

It is advisable to do a number of tests across the surface to ensure results are consistent.

Note temperature and dew point can affect this test.

 

Values and numbers indicated are general guidelines and recommendations and may not be applicable for some specific installations and conditions.

 

General

Apply to dust free, chemical free porous surfaces only.
Caution on new concrete, best to allow minimum 28 days curing prior to sealing (industry standard).
Solvents require surface to be bone dry for application. Water based sealers allow for some tolerance of moisture present.
Do not apply when surface temperatures are below 10 or greater than 28 degrees.
Do not apply if rain is imminent.
Repeated thin, evenly spread coats are better than a heavy application. Do not apply thick.
Single packs apply using 10-12mm nap roller or pump sprayer for best effects.
Two packs apply using 14-16mm nap roller or squeegee.
Application must not be too thick as excessive build up may cause the coating to appear milky or increase risk of delamination.
Application of sealer over contaminants such as moisture and dirt may reduce adhesion and cause discolouration.
Always apply to a small area first (approx. 1m2) and leave to dry to establish both suitability and coverage rate.
Coverage will vary depending on porosity of the surface and will range between 2sqm per litre on porous surfaces, and up to 12sq per litre on very smooth surfaces. Consult specific product page for recommended minimum/maximum spread rates.
Before applying the sealer, surfaces should be acid etched using a 5:1 hydrochloric acid wash.
Ensure all safety equipment is worn.
After the surface has reacted (approx. 20 mins) wash the residue off.
Ensure that disposal of residue is in accordance with local laws.
Ensure the surface is clean and dry before applying sealer.

NEW CONCRETE FLOORS
New concrete floors should be allowed to cure at least 28 days (industry standard) before painting. Cracks and crevices should be filled to ensure a level surface. The entire surface must be thoroughly scrubbed with a hydrochloric acid solution, followed by thorough rinsing with clean water and complete drying.
Before painting ensure that the surface is free from dust, grease and any other contaminants. Never apply on very damp floor surfaces or onto surfaces known to suffer from rising damp. If surface suffers from rising damp apply a moisture barrier first.
OLD CONCRETE FLOORS
Remove and or repair any cracked or damaged areas to ensure a level surface. Remove all unsound paint by scraping and sanding. If the entire floor is unsound it may need to be abraded/grinded or sandblasted. The entire surface must be thoroughly scrubbed with a hydrochloric acid solution, followed by thorough rinsing with clean water and complete drying.
Before painting ensure that the surface is free from dust, grease and any other contaminants. Never apply on very damp floor surfaces or onto surfaces known to suffer from rising damp. If surface suffers from rising damp apply a moisture barrier first.
PREVIOUSLY PAINTED SINGLE PACK
Product can go straight over any sound existing coating. If any peeling/flaking parts these will need to be removed. A coating is only as good as its preparation so if applied to an unsound surface the risk of delamination increases.
If a single pack solvent were previously used then best to re-apply a solvent once more.
If a single pack water based were previously used then best to re-apply a water based product once more.
CSW Coatings supply both water and solvent based products.

If existing surface is not sound (peeling/flaking parts) these will need to be completely removed either chemically with a product like:
Floor Stripper
https://cswcoatings.com.au/product/floor-stripper/
or mechanically with sanding/grinding or sandblasting (determined by applicator).

Due to the many variables in the field CSW Coatings cannot advise on applying our products over specific competing brand products.

PREVIOUSLY PAINTED TWO-PACK EPOXY
Floors that have been previously painted with two-pack epoxy can be recoated. The entire surface must be thoroughly abraded, preferably by sanding or sandblasting, in order to achieve a sufficient key for the paint to adhere to. Any loose, peeling or flaking paint must be removed. The surface can be abraded with a belt sander, pole sander or angle grinder using coarse sandpaper or grinding discs. Sandblasting, sanding and grinding are the recommended techniques for preparation. Pressure washing is NOT an adequate preparation technique. Failure to adequately abrade the epoxy coating can result in failure of the topcoat. Once a sufficient grind has been achieved pressure wash the entire surface to remove any sanding residue, leave the surface to thoroughly dry. Repair any damaged areas with a cement/sand mixture, or suitable epoxy filler. Ensure that the repaired surface/s are appropriately abraded before applying the paint.

Penetrating Sealer Preparation

Option 1 (manual)

Instructions

1. Sweep surface removing loose dirt, dust and debris.

2. Saturate surface with garden hose.

3. Apply Moss, Mould & Mildew Cleaner according to directions.

4. Saturate the head of a stiff bristled broom and start scrubbing the surface.

5. Once scrubbing is complete, rinse the surface thoroughly removing all Moss, Mould & Mildew Cleaner.

6. If using a water based sealer simply wait approx 20 – 40 mins before applying the sealer. Surface may be slightly damp (no pooling). If using a solvent sealer allow the surface to dry for approx 24 hours.

 

Option 2 (mechanical)

Instructions:

1. Use a blower on surface removing loose dirt, dust and debris.

2. Saturate surface with garden hose.

3. Apply Moss, Mould & Mildew Cleaner according to directions OR

4. Using a pressure cleaner, insert the chemical injector hose / venturi hose into bucket containing Moss, Mould & Mildew Cleaner.

5. Using pressure cleaner on low rpm apply solution liberally across surface. Do not allow to dry.

6. Optionally saturate the head of a stiff bristled broom and start scrubbing the surface.

7. Pressure clean surface.

8. Once pressure clean is complete, rinse the surface thoroughly removing all Moss, Mould & Mildew Cleaner.

9. If using a water based sealer simply wait approx 20 – 40 mins before applying the sealer. Surface may be slightly damp (no pooling). If using a solvent sealer allow the surface to dry for approx 24 hours.