Selleys VP30 Primer

What is Selleys VP30 Primer, and where should you use it?

Selleys Liquid Nails VP30 Primer is a one component, rapid curing, water-based hybrid polymer priming concentrate for porous and non-porous surfaces. Its main role in the Selleys Liquid Nails timber flooring system is as a bridging primer between Liquid Nails VBS or VBS Rapid and Liquid Nails SLC50 levelling compound.

It also has two broader uses. It can be used to prime concrete before applying VBS, VBS Rapid or SLC50, and it works as a versatile primer for other porous and non-porous substrates before applying adhesives, skimming plaster or cementitious self levelling compounds.

The thing that catches people out is the dilution, because it changes depending on what you are priming: undiluted for non-porous surfaces, and diluted 1:1 with water for porous ones. Use the wrong one and both the coverage and the result change.

Technical specification

Property	Typical result
Technology	Water based hybrid polymer system
Colour	Red opaque liquid
Density	1.07
Packaging	5L plastic jerrican
Mix ratio	1:1 with water for porous surfaces; undiluted for non-porous surfaces
Coverage	18–20m² per litre for non-porous surfaces; 10m² per litre for porous surfaces
Coverage per pack	Approximately 100m²
Application temperature	10 – 35°C
Cure time / overcoat time	30 minutes to 2 hours, depending on temperature and humidity
VOC content (ASTM D3960-05)	14 grams per litre

These figures are indicative data only and are not intended for the preparation of specifications.

What the key numbers mean in practice

The two coverage rates are not a range — they are two different jobs. On a non-porous surface such as cured VBS or VBS Rapid, you apply the primer undiluted at 18–20m² per litre. On concrete or screed, you dilute it 1:1 with water and apply at roughly 10m² per litre. Concrete drinks primer; a sealed epoxy surface does not, so it needs a much thinner spread to leave the same film.

Both figures work back to the same pack figure: each pack will cover approximately 100m².

Cure is stated as 30 minutes to 2 hours, depending on temperature and humidity. The headline feature is "rapid cure — as fast as 30 minutes", and 30 minutes is the fast end of that range, not the number to plan a schedule around. Cold, humid conditions push it towards two hours. Good ventilation of the space will speed up the rate of cure.

What you are actually waiting for is a state, not a clock reading: the primer must have dried clear over the entire job and be able to be walked on without tackiness before the self-levelling compound is poured. Check the whole floor rather than the patch near the door, because thin and thick areas dry at different rates.

Once cured, VP30 will not re-emulsify in water. That is what makes it viable under a wet, cementitious levelling compound — the primer stays put rather than softening when the SLC50 goes over it.

Why a bridging primer is needed at all

A cured epoxy vapour barrier is a smooth, sealed, non-porous surface. A cementitious self-levelling compound poured directly onto it has very little to grip. VP30 sits between the two and gives the levelling compound something to bond to, which is why Selleys calls it a bridging primer.

On bare concrete the primer is doing a different job — sealing a porous substrate. The reason for that is set out on the SLC50 data sheet: sealing the substrate prevents air release from the subfloor rising and forming bubbles and pinholes in the surface of the levelling compound. Either way, ensuring a film is present on the surface after application is what makes the primer work.

Where to use it

• As a bridging primer between Liquid Nails VBS / VBS Rapid and Liquid Nails SLC50 levelling compound
• To prime concrete before applying VBS / VBS Rapid or SLC50 levelling compound
• As a versatile primer for other porous and non-porous substrates before applying adhesives, skimming plaster or cementitious self levelling compounds

Selleys notes it has optimal properties for use as part of the Selleys Liquid Nails timber flooring system, and adds that if you are using an alternative system, an adhesion check is recommended.

Surface preparation

• All surfaces must be free of contaminants, and clean and dry prior to use.
• Dusty substrates such as ground concrete should be vacuumed well until dust free. A primer applied over dust bonds to the dust, not the slab.
• No surface preparation or sanding is required beyond cleanliness — this is one of the product's stated features.

How to apply it

Over VBS or VBS Rapid (non-porous):

1. Wait until the VBS or VBS Rapid is sufficiently cured across the whole job that it can be comfortably walked on without tackiness. For VBS this will typically be overnight; for VBS Rapid, a minimum of 2 hours in good drying conditions.
2. Do not dilute. VP30 goes on undiluted over VBS, VBS Rapid or other non-porous surfaces.
3. Brush the edges of the room, then apply with a roller at 18–20m² per litre, ensuring a continuous film has been attained.

Over concrete and screed (porous):

1. Dilute VP30 1:1 with water.
2. Brush the edges of the room, then apply with a roller at approximately 10m² per litre.
3. Ensure a film is present on the surface after application, to optimise adhesion of the self-levelling screed or of VBS / VBS Rapid.

Then, before pouring: the primer must have dried clear over the entire job and be able to be walked on without tackiness before the self-levelling compound is poured. Ventilate the space well to speed the cure.

Limitations

• In unusual circumstances, two coats may be required on very porous concrete.
• Not suitable for some metals or plastics — pre-test adhesion before use.
• Do not apply over contaminated or dusty surfaces.
• Not suitable for surfaces subject to standing water.
• Apply within the stated 10–35°C application temperature range.
• If using an alternative system rather than the Selleys Liquid Nails timber flooring system, an adhesion check is recommended.

Clean up and storage

Clean up with water before the product cures, using damp rags to remove any splatter from walls. Once cured it will not re-emulsify in water, which is exactly the property you want in the floor and exactly the problem you have on a wall — so deal with splatter as it happens.

The product is low odour, has a VOC content of 14 grams per litre, and meets the GBCA VOC content requirement. Store in a cool dry place out of direct sunlight, keeping containers sealed when not in use. Warnings, first aid and shipping information are on the product SDS available through the Selleys website.

Hazard classification

Classified as hazardous under Safe Work Australia GHS 7, with the signal word Warning.

• Skin corrosion/irritation — Category 2. H315: causes skin irritation.
• Eye damage/irritation — Category 2A. H319: causes serious eye irritation.

VP30 Primer is not classified as Dangerous Goods under the Australian Code for the Transport of Dangerous Goods by Road & Rail or New Zealand NZS5433.

What is in it

Chemical entity	CAS number	Proportion (w/w)
1,3-Benzenedimethanamine	1477-55-0	<1%
Triethylenetetramine	112-24-3	<1%
Non-hazardous or below reporting limits	—	Balance

The primer is a red opaque liquid with a specific gravity of 1.07, miscible with water. That last property is the one that matters on site: while it is wet it dilutes and washes, and once it has cured it does neither — which is the same fact the clean-up instructions are built on.

The two declared ingredients are the same amine family that makes up the hardener side of the VBS systems this primer is designed to bridge, but here they are present at under 1% each. The difference in dose is the whole difference in hazard. VP30 is Warning rather than Danger, it is not Dangerous Goods, and — unlike the VBS hardeners — it carries no skin sensitisation classification. It irritates; it is not recorded as teaching the immune system to react.

Two practical points follow. First, the eye classification is Category 2A on a product that is rolled or broomed onto a floor, sometimes diluted and sometimes not, often with the applicator moving towards the operator. Eye protection is cheap insurance for a job that looks like painting. Second, the safety data sheet asks you to avoid inhaling vapour, mist or aerosol; that sits comfortably with the ventilation the directions already recommend to speed the cure, but it is a reason to ventilate even when you are not in a hurry.

Protection

• Eye protection — safety glasses.
• Gloves — nitrile rubber is indicated for intermittent contact; make your own final assessment for your conditions and glove construction.
• Clothing — overalls and safety shoes. Wash contaminated clothing and protective equipment before storing or reusing.
• Ventilation — avoid inhaling vapour, mist or aerosol. Keep eyewash and a safety shower close to the work area.
• Storage — cool, dry and well ventilated, out of direct sunlight, containers sealed when not in use.
• Wash hands before eating, drinking, smoking or using the toilet.

First aid

Exposure	What to do
Eyes	Hold the eyelids apart and flush continuously with running water — until told to stop by the Poisons Information Centre or a doctor, or for at least 15 minutes — then go to a doctor or hospital.
Skin	Remove contaminated clothing immediately and flush skin and hair with running water, continuing until told to stop or for 15 minutes, then go to a doctor or hospital.
Inhalation	Move the person to fresh air without becoming a casualty yourself. Loosen tight clothing, let them rest comfortably and keep them warm until recovered. Seek medical advice if effects persist.
Swallowed	Rinse the mouth with water. Do NOT induce vomiting. Give a glass of water. Never give anything by mouth to an unconscious person. Seek medical advice.

If poisoning occurs, contact a doctor or the Poisons Information Centre — 131 126 in Australia, 0800 764 766 in New Zealand — with the container to hand. Selleys emergency line: 1800 220 770 in Australia, 0800 220 770 in New Zealand.

Common questions about Selleys VP30 Primer

Do I dilute it or not?

It depends on the surface. Undiluted over VBS, VBS Rapid and other non-porous surfaces; diluted 1:1 with water over concrete, screed and other porous surfaces.

How much will it cover?

18–20m² per litre on non-porous surfaces, or approximately 10m² per litre on porous surfaces. Each 5L pack covers approximately 100m².

How long before I can pour the levelling compound?

Cure is 30 minutes to 2 hours depending on temperature and humidity. The test is not the clock — the primer must have dried clear over the entire job and be walkable without tackiness.

How long after applying VBS can I prime?

Once the VBS or VBS Rapid can be comfortably walked on without tackiness across the whole job. Typically overnight for VBS, and a minimum of 2 hours for VBS Rapid in good drying conditions.

What do I apply it with?

Brush the edges of the room first, then roll the rest.

Do I need to sand or key the surface first?

No surface preparation or sanding is required, but the surface must be clean, dry and free of contaminants, and dusty substrates such as ground concrete must be vacuumed until dust free.

Will it wash off once it has dried?

No. Once cured it will not re-emulsify in water. Clean up splatter with water before the product cures.

Can I use it on metal or plastic?

It is stated as not suitable for some metals or plastics. Pre-test adhesion before use.

Can I use it where water will sit on the floor?

No. It is not suitable for surfaces subject to standing water.

What if the concrete is very porous?

In unusual circumstances, two coats may be required on very porous concrete.

Does it meet Green Star VOC requirements?

Its VOC content is 14 grams per litre, and it is stated to meet the GBCA VOC content requirement.

Can I speed up the cure?

Good ventilation of the space will speed up the rate of cure.

What does it go between?

Most often between a vapour barrier — VBS Vapour Barrier or VBS Rapid — and SLC50 Leveller. The full system is set out under flooring.