Toplight C

Lightweight structural concrete


Toplight C is Tarmac's lightweight structural concrete produced using specialist engineered high strength lightweight aggregate and admixtures to provide much lower densities compared to standard conventional concrete.

Toplight C can be produced with a density of 1800-1900 kg/m3. Structural concrete strengths can be gained up to 50N/mm2 compressive strength with non-structural mixes being possible with densities as low as 1000kg/m3.

Toplight C is available with lower carbon savings, read more about our sustainable concrete here.


Where can Toplight C be used?

Toplight C can be used in any application where normal weight concrete is specified as follows: 

To create lighter concrete slabs, foundations, floors and walls to reduce loads on structures.

Lightweight structural concrete for reinforced concrete slabs

Using Toplight C, designers can not only look to reduce the thickness of the slab, columns and foundations but also reduce the amount of steel mesh required resulting in a quicker more cost-effective greener building.

Lightweight structural concrete for composite metal decking

Toplight C is ideal for composite metal decking. As spans increase the deflection becomes the defining factor. The use of Toplight C minimises the weight by up to 30% therefore reducing the deflection.

Why use Toplight C?

Reduces the weight over conventional concrete by 30% for structural applications.

Reduces the need for propping on metal deck floors improving completion times.

Environmentally friendly – The lightweight aggregate we use in Toplight C is an expanded raw material, producing 300% more aggregate per cubic metre than quarried aggregates thereby reducing demand on natural resources. 

Reduces the weight over conventional concrete by 60% for non-structural applications.

Can be pumped and placed like normal weight concrete.

Improved fire resistance over normal weight concrete.

Can support the reduction in steel and foundation size in structures.

Improved thermal and acoustic properties over normal weight concrete.

Reduces cold bridging.

60 London Wall

Lightweight structural concrete for composite metal deck floor extension

Learn More

Nobu Hotel, London

Lightweight structural concrete for hotel rooftop extension at a luxury hotel in Shoreditch

Learn More

Planning a project?

Speak to one of our technical experts to learn how Toplight C could transform your next project.

Contact us

How it works

Harnessing the power of admixtures & Specialist Aggregates 
Key to the exceptional performance of Toplight C is the presence of tailored admixtures and specialist engineered lightweight aggregates in the mix. These materials provide improved fire resistance compared to conventional concrete and a reduced weight by almost 30% in structural and 60% in non-structural concretes. 

High Strength & Fluidity in complex environments
Thanks to the presence of specific admixtures and specialist aggregates, Toplight C provides a lightweight concrete which can still reach strengths of up to 50N. It can be pumped, placed and compacted similar to conventional concretes whilst providing all the required benefits of a lightweight concrete in challenging environments.


The aggregate we use in our lightweight concrete complies to BS EN 13055, designed in accordance with BS EN 206-1 and BS 8500. 

Toplight C contact


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