Deep Barrier

DEEP BARRIER is a non-membrane forming moisture barrier for concrete that works in the slab and not on the concrete surface.

Why a moisture barrier for concrete?

At the time of pour, a cubic metre of concrete typically has 190-195 litres of water. Over the next 28 days during the process of hydration some 120 litres leaves the concrete. As the water tracks out it leaves porosity or capillaries through the thickness of the concrete where any moisture present can move in or out.

A common myth is that concrete is dry as soon as it can be walked on.

To conform to the Australian standard (AS 1884-2021), concrete must have a MVT (moisture vapour transmission) of no greater than 10g per sqm in 24 hours.  The NATA Lab test results came in at an average of 3.60 grams – only 36% of the maximum allowed.

In normal conditions an average slab of 100mm thick can take 4-5 months of drying time before it will conform to that standard. This is approx 20-25mm thickness of concrete per month

And even when the concrete conforms to the Australian Standard, if water is present the concrete will still act like a sponge and continue to absorb water, causing high moisture levels.

Testing for excess moisture:

85% of flooring failures are due to the presence of moisture in concrete from hydro-static pressure or green concrete.

The majority of floors are never tested for moisture levels. With the correct equipment it is a very simple and easy test to do.

When testing the slab moisture content after application, by using a 2 prong tester or an in-situ probe test, it is guaranteed that the result will be high and false.  Deep Barrier holds the moisture in the slab, and stops moisture transmission (MVT) through the slab and out on to the outer top surface.  The correct way is to use the Hydro-hood method of testing.

• Wastes valuable time and money having to re-do jobs and repairs
• This annoys the customer, wasting their time and money sorting out the floor problems

Once a floor has been installed any moisture present will be drawn to the surface. If there is no way of escape for the moisture it will react with any adhesives or coatings on the surface of the concrete.

How to prevent moisture problems:

Waiting for the concrete to dry is not an option. This means you will have to use a waterproofing agent so you can get on with the job and to prevent any potential moisture problems.

The two main methods are either a membrane on the top surface of the slab (the traditional method) or to use an internal penetrating barrier.

• Membrane forming moisture barriers – are sprayed on to the concrete surface forming an impermeable skin. These compounds are applied generally 28 days after pour, done in 2 coats with a 12 hour wait in between. Then you have to wait another 12 hours before you can lay any flooring. They can be very easily damaged during the construction process, and rely on the skill of the applicator to ensure that there are no pin holes left where moisture can escape.
• Penetrating or internal moisture barrier – these compounds do not form a membrane but penetrate the concrete surface, react with the cement powder and turn to a gel, blocking the movement of moisture out of the slab. They also cure, harden / densify the slab, and help prevent efflorescence. They do not slow down the construction program as with the other type of barrier. We had one job where the 200mm thick slab was poured and within 14 days the flooring contractor was laying sheet vinyl.

DEEP BARRIER ‘ticks’ all the boxes for being a fast, cost effective solution when you need a moisture barrier for concrete.

Knapsack / back pack sprayer

Airless sprayer

Typical use areas:

1. Concrete floors and raft slabs / footings
2. Concrete pavements
3. Precast concrete elements
4. Balconies, roads and runways
5. Buildings, bridges and infrastructure

Key Features:

1. Safe and easy and fast application
2. Can be walked on within 15-30 minutes
3. Cannot be damaged during the construction process
4. Complies with the AS 1884 Resilient Flooring Standard
5. Assists in the prevention of efflorescence and concrete cancer
6. Enviro-friendly, odourless, non-toxic and waterbased
7. Assists in the adhesion of coatings and adhesives
8. Improves chemical resistance
9. Prevents moss and mildew growth

Technical Information:

• Vehicle Type: Water based
• Viscosity: 2.4
• Specific Gravity: 1.1
• Drying time: 30 minutes @ 25ºC
• Finish: No change to substrate
• Colour: Opaque – dries clear
• Theoretical Coverage: 4.0 – 4.5m²/litre
• Freezing point: -20C
• Boiling Point: 1000C
• Abrasion Resistance: Excellent
• Bacterial Resistance: Excellent
• Chemical Resistance: Excellent
• Heat Resistance: Up to 1200C (dry heat)
• Solvent Resistance: Good
• Salt Spray Resistance: Good
• Thinning and cleaning: Water
• Durability: Excellent
• VOC Content: None
• Surface Bond: Excellent

Key Features:

• Equipment: Non Atomizing Spray e.g. Use knapsack or backpack, airless spray or us a coarse bristle broom.
• Cleaning: Water.
• Typical Specification: One coat, however if applied over a very old/porous concrete 2 applications may be required due to the porosity.
• Floor preparation: After DEEP BARRIER application there is no membrane on the slab surface. The Flooring Standard requires that if any product that forms a membrane is used, then it must be removed by grinding or similar prior to using adhesives etc.