A Revolutionary Technology is Invented

In the USA in early 70's Bill Ward received a call from his previous employer about an offshore oil well that had blown out. Back pressure build up was forcing oil to leak through the casing and the pressure build up could not be stopped. The company was in danger of losing the offshore well.

At the time there was no known solution.

The company looked to Ward, a known problem solver. He said he had something that might work. Ward had invented a technology that could plug pores in concrete to stop bleed water migration. The company had enough confidence in Ward to try it.

The company barged in loads of concrete and about 300 drums of Wards product. They pumped the product down one side of the dual pipeline and poured concrete down the other side.

When the chemical and the concrete merged, the concrete quickly hardened. The pipe was permanently sealed. This was a significant accomplishment, especially because of the extreme pressure build up. Shortly thereafter, Bill used this procedure to save another offshore well.

Using the funds received for saving the wells, Ward began refining the product, concentrating on an environmentally clean technology that penetrated the pores in concrete. Ward focused his attention in the laboratory to perfect the manufacturing process. Without any marketing efforts, the products were sold and used world-wide.

Ward and his wife Darlene's company, DARCHEM, continued to develop chemical products to enhance concretes durability, permeability and overall concrete performance, including materials formulated to deeply penetrate, moisture-proof, and protect concrete.


In 2010 DARCHEM granted exclusive rights to control the technologies Bill Ward had developed to Spray-Lock Concrete Protection LLC of Chattanooga, Tennessee, USA.

Down Under

Protect Crete/Oxtek products have been manufactured in Melbourne Australia since 1998, using raw materials imported from Darchen/Spray-Lock USA.

Protect Crete Pty Ltd now renamed Oxtek Pty Ltd have over the past 16 years developed a broad knowledge of concrete design, chemistry, placement and remediation enabling them to produce a unique range of sustainable user-friendly products which solve specific performance and durability issues with concrete.

New Zealand

In 2006 Protect Crete Ltd was established by Bill and Jennifer Irvine to import and promote the full range of Protect Crete/Oxtek products in New Zealand.

New Zealand Wide Distribution

Shortly afterwards Gilt Edge Industries Ltd were appointed Master distributors with the responsibility to service the whole country and make Protect Crete/Oxtek products easily accessible and professionally supported.

Over the past 45 years Gilt Edge have evolved from a small manufacturing base in Christchurch to become the leading solution provider and wholesaling distributor in NZ for flooring and construction, installation and preparation products.

Gilt Edge have an energetic and highly experienced professional team of 24 people servicing the NZ market from a dozen locations.



Protect Crete Products

Are Green Star Compliant!

Protect Crete products have recently been tested for VOC compliance by Cetec-Foray under the specification of the Green Building Council of Australia and they passed easily with well under 1 gram per litre meeting the criteria of Green Star.

Earlier testing by Melbourne laboratory Environmental Consulting Pty Ltd gave values of less than one 500th of a gram per litre, virtually none. This brings together and completely reinforces Protect Crete's commitment to providing safe and sustainable concrete solutions giving architects and clients peace of mind.

Protect Crete's Densi-Proof and Moisture-Fix have been providing guaranteed moisture control for the New Zealand flooring industry for the last 8 years, enabling resilient floor coverings, paints and coatings to be applied to new or existing concrete without the risk of failure from moisture related issues.

Protect-Crete and now our new Oxtek brand products provide a wide range of concrete protection and life extending solutions. Use our new product selector to help you find the Protect-Crete or Oxtek product most 'fit for purpose' to enhance the performance of your concrete.


Contact us by email or telephone to discuss your requirements in detail.

Green Star Compliance Certificates: