ONE BROADGATE:

A sustainable statement

The Project

In London, and in particular the City of London, building designers have often chosen to awe. The result has been structures that stretch into the sky, gleaming with glass and the intention to intimidate, with less thought being bestowed on the building’s future inhabitants.

One Broadgate breaks with this trend. Wrapping around the Broadgate Circle, it rises in gradual, stacked increments. Seeking to blend into rather than dominate its surroundings, its 13 floors reflect neighbouring buildings with an autumnal colour palette that gets lighter as the building ascends.

This gentle facade is complemented by private terraces that trail across each level, giving the future workers of its 375,000 square feet of retail space and 375,000 square feet of offices an easy escape into greenery. 

But consideration towards well-being has not ended there. Smart technology gifts its inhabitants complete control over their indoor conditions, while a mixed-mode ventilation system allows for enhanced fresh air circulation, all of which is controlled by sensors.

Stirling Prize-winning architects AHMM have also turned their attention to the well-being of the planet. Circular economy principles have been adopted throughout the design and procurement stages while advanced energy modelling has been used from the very earliest stages.

Glazed areas have been mixed with shading structures to optimise natural light and solar gains into the building. In addition, highly efficient heat pumps, heat recovery systems and energy storage units have been installed to cut energy consumption.

As a result, One Broadgate is targeting a BREEAM Outstanding rating and is one of the first UK Design for Performance projects from the Better Building Partnership. Upon completion, it is expected to receive a Base Building Energy Rating of 4.5 to 5 stars. 

The Blockwork Solution

A smart and forward-thinking project such as this needed a block that would support more than just its structure. It also needed a partner that could fit in with a tight building programme and respond flexibly to changes. Builders merchants EH Smith and project builders Lesterose therefore turned to us and our flagship Lignacite blocks.

These medium-dense blocks are robust and durable, ideal for both loadbearing and non-loadbearing applications in large-scale structures. This outstanding technical performance is achieved thanks to the inclusion of recycled wood particles within the product’s mix, something that also makes these blocks appealing in sustainable construction.

As no finish would be applied to the final surface, our Fair Face Lignacite product was selected as the ideal choice. Designed to be left unadorned by paint, plaster or render, these blocks have colour consistency maintained through careful manufacturing processes. This meant that we fulfilled the order in controlled batches to ensure an even and appealing final finish. 

These were chosen in sizes 100mm and 140mm. The latter (also known as Lignacite SP) has a specially formulated mix that optimises its density. This means that you get a solid block with a unit weight of less than 20kg, the maximum weight for manual handling. As such, it is a practical choice for large-scale projects.

The insulative properties of these blocks also made them a good selection. Boasting low air permeability, the blocks contribute towards the building’s air tightness, reducing the loss of heat from the structure. The thermal mass of the blocks themselves also contribute towards One Broadgate’s internal comfort: in hot weather, the blocks can help to absorb heat, releasing it at night. This reduces the need for high-energy artificial means of cooling.

Lignacite blocks support the project’s values on well-being too. Their excellent sound insulation means that future shoppers, diners, and office and retail workers will be protected from excess external noise, which can be damaging to health.

To deliver the blocks and support the project’s scheduling, we organised early morning deliveries and kept lead times to a minimum. This gave Lesterose the flexibility they needed to adapt to change.