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CONVERT RUST ON PITTED METAL

REFERRO

RUST CONVERTER FOR BADLY RUSTED METAL ROOFS

 

Appearance

White - Dries Clear

Covarage

8-10 m² per litre (per coat).

Available Sizes

Referro is SealPro's rust converter for metal that has gone past surface rust: pitted roof sheeting, rusted screw lines and overlaps, corroded flashings and gutters. Applied to the wire-brushed rust, it reacts with the iron oxide and turns it into a stable, bluish-black layer that primes and seals the treated area.

Referro is a spot treatment. Once the rusted areas have turned uniformly black, prime the complete roof with Purple Prime, so every sheet, treated or not, has the same rust-inhibiting base before the topcoat goes on. That way nothing is missed.

Ideal for

Rusted metal roof sheeting IBR, corrugated, Widedek and Zincalume roofs where rust has pitted the sheet.

Screw lines, overlaps and flashings The places where rust starts first and creeps under old paint.

Gutters and valleys Metal that holds water and rusts from the inside out.

Steel structures and silos Warehouse frames, grain silos and tanks with corrosion on exposed steel.

Gates, palisades and farm equipment Rusted steelwork that needs treating before it is repainted.

HOW IT WORKS

HOW IT WORKS CONVERT THE RUST, THEN PRIME THE ROOF

Rust is iron oxide, and it keeps spreading under paint until something stops it. Referro is an acidic, water-based polymer emulsion that reacts with the iron oxide and converts it into ferric tannate: a hard, inert, bluish-black layer that seals the treated area against moisture and oxygen. You can see it working. Referro goes on milky brown and turns bluish-black as it reacts. A uniform black finish tells you the rust has been converted. One coat is enough.

Referro is a rust treatment, not a finish. Once the treated areas have cured, prime over them with Purple Prime and finish with a SealPro topcoat.

Which product do I need?

The metal you are working on What to use
Badly rusted, pitted metal Referro on the rust spots, then Purple Prime on the full roof
New, pre-painted or lightly rusted metal, including Chromadek and galvanised Purple Prime, then a SealPro topcoat
Sound metal that needs a quick one-product maintenance coat SteelPro 3-in-1 (when in doubt, prime with Purple Prime first)

KEY BENEFITS

1/ STOPS RUST IN THE PITS

A wire brush removes loose rust but cannot get pitted metal back to clean steel. Referro converts the rust left in the pits, seams and screw holes.

2/ NO SANDBLASTING

Wire-brush the loose rust and debris, then let Referro deal with what is left. Cheaper, faster and far less messy than blasting a roof.

3/ PRIMES AND SEALS THE TREATED AREAE

The converted layer seals the spot against moisture and is ready for Purple Prime.

4/ YOU CAN SEE WHEN IT'S DONE

Milky brown going on, clear bluish-black when the rust is converted. You can see exactly which areas have been treated.

5/ WATER-BASED AND EASY TO APPLY

Apply by brush, roller or airless spray, straight onto the prepared rust.

GETTING STARTED

PREPARATION & APPLICATION

Surface Preparation

The cause of most coating failures is poor surface preparation.

  1. Wash and degrease. High-pressure wash the whole roof with a degreaser and detergent to remove dirt, grease and chalky old paint. Let it dry completely.
  2. Remove loose rust. Wire-brush or mechanically clean the badly rusted, pitted sections until all loose rust scale, flaking paint and debris are gone. Referro converts the rust that stays in the pits; it does not replace removing loose material.
  3. Dust off. Remove all dust and debris just before you apply Referro.

Application Instructions

  • Stir well before use.
  • Apply one full coat to the rusted areas only, by brush, roller or airless spray. Lay down an ample coat and work it into pits, screw heads and lap edges. One coat is enough.
  • Apply to a dry surface. Do not apply if rain is expected before it is touch dry.
  • Touch dry in 1–2 hours. The treated areas turn bluish-black as the rust converts.
  • After 6–12 hours, prime the complete roof with Purple Prime.
  • Coverage: approximately 9 m² per litre (20 L treats about 180 m²).

THE COMPLETE METAL ROOF SEQUENCE

  • Wash and degrease the full roof.
  • Wire-brush and spot-treat badly rusted sections with Referro.
  • Prime the complete roof with Purple Prime.
  • Waterproof screw lines and overlaps with the StretchSeal Flex system.
  • Seal each screw head with ScrewSeal patches.
  • Finish with a SealPro topcoat: Cool Roof, SteelPro, or the HydroSeal HF waterproofing system.

APPLICATION

Brush, roller or airless spray. Touch dry in 1-2 hours.

IMPORTANT

NO PERFORMANCE GUARANTEE
Referro is a rust treatment, not a protective finish. As with all rust converters, SealPro does not offer a long-term or performance guarantee on Referro. How well it holds depends on how far the rust has progressed, the surface preparation, application conditions and exposure, all of which are outside our control. For lasting protection, follow Referro with Purple Prime and a SealPro topcoat, and speak to our technical team before you start on a large or badly corroded roof.

CASE STUDIES

REFERRO RUST CONVERTOR AT WORK

Badly rusted metal is one of the most common reasons a roof needs more than a coat of paint. These projects show Referro used the way it is meant to be: convert the rust spots first, then prime the whole surface.

CENTURION A commercial building in Centurion had rust pitting along its roof sheeting. The roof was washed and cleaned, and the rusted sections were wire-brushed and treated with Referro. Once the treated areas had turned black, the roof was primed with a metal primer and finished with Cool Roof.

Rust was shortening the life of a metal grain silo. After cleaning, the corroded areas were treated with Referro, converting the rust into a stable black layer. The silo was then primed, given a ThermoSeal heat-insulating coat and finished with Cool Roof.

WORK WITH US

Let our technical support team help you find the right solution for your application.

SPECIFICATIONS

EVERYTHING YOU NEED TO KNOW.

1/ PRODUCT INFORMATION

Downloadable product information data sheets.

Download PDF (0.63 Mb)

2/ APPLICATION METHOD

Downloadable product method statement.

Download PDF (0.59 Mb)

CONTACT

NEED TO KNOW MORE?

LET'S TALK.

The success of any project depends on the type of product and the correct application of the solution. The SealPro technical support team has experience in all specialised coatings we supply and can help you to find the correct product & solution for your application.

+27 60 997 6364

Monday to Friday.
7:30 am to 4:30 pm.

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