Ultralight Postmix

Lightweight bag, heavyweight performance


Ultralight Postmix makes setting posts easier from start to finish. Half the weight of conventional concrete, the lightweight formulation is easier to lift, easier to carry and easier to transport. High quality, strong formulation for setting all types of wooden, concrete and metal posts.

Where can Ultralight Postmix be used?

Fence posts

Ultralight Postmix is ideal to use for fence posts.

Gate posts

Ultralight Postmix can be used for gate posts.

Rotary washing lines

The properties within Ultralight Postmix make it ideal for rotary washing lines.

Why use Ultralight Postmix?

Case studies

Additional info

Typical Performance - Initial set time: 5-10 minutes depending on conditions – cool temperatures retard, warm temperatures accelerate. Typical compressive strength achieved at 28 days is 10N/mm2 .

Typical Coverage - One 10kg bag is required per standard fence post. When mixed with water one bag will cover approximately: 0.12m2 at a depth of 75mm 0.09m2 at a depth of 100mm.

Usage instructions - Recommended ambient application temperature is 5 oC to 25oC. Do not use when air temperature is below 5oC or when ground is frozen.

Protect newly placed Ultralight Postmix against frost and rain by using hessian or polythene sheeting. In dry or windy conditions, do not allow the Ultralight Postmix to dry out too quickly. Allow concrete to dry sufficiently before proceeding with further works.


Ultralight Postmix contact


Nationwide network

UK Coverage

Tarmac is a national network of localised businesses, offering construction material supply. In addition, our building products division has a nationwide network of 19 production and distribution plants, including co-located plants with our internal quarries, which enables us to provide an efficient service across the UK.

Continual improvement

We are continually investing in new plant, manufacturing and bagging technology to ensure quality consistency and our commitment to the ‘Ultimate Manufacturing’ framework empowers us to deliver continuous operational improvement.

Promotional support

Marketing materials

Our products aren’t just easy to use, they’re easy to sell. We offer our stockists a full range of high impact support materials from point of sale materials, to yard banners and posters, not only that, our products are available in attractive, durable, rip resistant poly packaging. 

Website ready

We understand that web activity is more important than ever with many consumers now browsing your website before buying. We have a descriptive text for each of our product range, along with a library of images for you to upload to your website to enhance product listings. 


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