Lloyd House eco-home, Kent
Environmental considerations and design were core threads running through the project which contributed to the client obtaining planning permission in a location of high landscape quality. The client had wished to build a house with a low carbon footprint in materials of construction, as well as being highly insulated, and using air source heat to give a low carbon footprint in use. A low-carbon alternative to concrete was considered from the outset. As such, Cemfree was the only suitable material which has support from manufacturer-supplied test certificates to gain approval by Building Control for this application.
Planning permission & paragraph 79
The eco-house design met the exceptional architectural quality and innovation criteria required by Paragraph 79 of the NPPF (previously known as Paragraph 55), providing special circumstances for a new dwelling in the countryside. Planning permission recognised the potential for the use of low carbon materials as an exemplar contributing towards improved environmental standards in other houses built locally and would contribute towards setting quality design standards for National and Local Planning policies, National Planning Policy Framework, Tunbridge Wells Borough Council and the High Weald AONB Management Plan.
A sustainable concept
Cemfree was chosen to replace concrete as a low-carbon material which could be poured on site similar to any traditional build. This innovative material, the first to be used in housebuilding to replace concrete, would significantly reduce the carbon footprint of material used in construction, one of the most important ambitions of sustainability.
This home is the first to use innovative ultra-low carbon cement structural concrete from ground blast furnace slag (GGBS) in its floors and retaining walls. The design by Sir Terry Farrell, stepped the house into the sloping site lower than neighbouring houses to minimise impacts on views from the surroundings. This concept needed significant retaining walls, and so the use of Cemfree was an opportunity to demonstrate effective and practical application of a low carbon material. The careful detailing of below-ground walls and floor levels using Cemfree, along with the sustainable architectural design, was carried out during the implementation by Place 54 Architects. Step Three Construction and Gallagher Group Readymix Concrete were contracted to make sure all went to plan with the build.
- Sustainability – for every kilo of OPC that wasn’t used for this project, there was a saving of 3kg of raw materials and 1kg of waste diverted from landfill with a potential carbon saving of up to 0.3 tonne per cubic metre. Cemfree is 95% by-product, supporting a circular economy
- Durability – Cemfree is extremely hardwearing and more chemical resistant
- Aesthetics – Cemfree is whiter than ordinary cement giving a brighter decorative finish
- Logistics – Cemfree doesn’t require modification to production and delivery plant, and little adaption of site methods is required
Site Manager, Step 3 Construction
“The project to build Lloyd House was our first experience of using the Cemfree product. We worked closely with the team throughout and achieved a good result. It’s doubly satisfying to know that such an environmentally friendly product was used in the construction of this building.”
Architect Nisha Vikaria, Director, Place 54 Architects
“Cemfree was chosen to replace concrete as a low carbon material which could be poured on site as a traditional build. This innovation, the first use in house-building to replace concrete, will significantly reduce the carbon footprint of material used in construction, one of the most important ambitions of sustainability.
A low-carbon alternative to concrete was considered from the outset. Cemfree was the only suitable material found which has support from manufacturer supplied test certificates to gain approval by Building Control for this application.”