When building or renovating heritage properties, you can’t help but think about the restrictions and the materials used.
One such material, which is often the preferred choice for such projects, is Lime Screed.
But its application isn’t just restricted to heritage properties.
Let’s dive deeper into the world of Lime Screed and understand its benefits, uses, and why it stands out as an environmentally-friendly option.
What is Lime Screed?
Lime Screeds, at their core, are analogous to traditional sand and cement screeds.
However, there’s one key difference: the lime replaces the cement as the binder.
Once set, it forms a strong subfloor screed.
- Mixing & Pumping: We prepare the Lime Screed by batching it to a pre-determined mix design. We use specialised equipment like a forced action mixer or a larger Putzmeister pump for installation.
- Placement: The screed is either pumped or wheelbarrowed into the construction site. It’s then meticulously laid using a screed bar and is trowel-finished.
- Finishing Standards: We can place the screed to SR2 Flatness standards. For projects demanding precision, we can even install it to SR1 (Super Flat) standards.
- Edging Materials: Depending on the project’s requirements, materials like cork can be used as an edging material to enhance permeability and ensure a wholly natural subfloor construction.
Incorporating Insulating Elements
One innovative approach with Lime Screeds is their combination with Recycled Foam Glass Insulating Hardcore, like Leica and Glapor. Companies like Tŷ-Mawr have popularised this technique.
ATS, for instance, frequently installs Tŷ-Mawr materials and has done so for numerous projects across Scotland.
Where are Lime Screeds Used?
ATS has extensively used lime screeds for diverse projects, ranging from listed houses to schools, museums, and churches.
For such applications, they typically opt for NHL5 (Natural Hydraulic Lime strength class 5), ensuring the screed’s strength.
Although drying times vary based on site conditions, laying floor finishes is standard after 21-28 days post-application.
An added benefit is that Lime Screeds are compatible with Under Floor Heating.
Breathability: A Defining Characteristic
Limecrete is notable for its breathability, which it shares with other natural building materials.
Being permeable, water vapour can effortlessly pass through the lime screed.
This attribute makes it an excellent fit for older-style construction or those keen on eco-friendly building methods.
Lime Screed: An Environmentally-Friendly Choice
A pivotal question arises: Why consider lime screeds from an environmental perspective?
The production of both hydraulic lime and other binders like cement emits CO2.
However, lime possesses a unique quality: as it sets, it reabsorbs CO2.
This distinguishing factor makes it environmentally superior to cement and other pozzolanic binders.
Lime Screed offers a sustainable and versatile solution for modern construction needs, whether for its environmental benefits, adaptability, or innate breathable properties.
Lime Screed emerges as a material of choice, especially for projects with heritage touches or green construction objectives.