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Drop-in floor insulation for timber suspended floors

by Brad Stuart | Apr 2, 2025

An alternative to polystyrene, Terra Lana Drop-in Floor Insulation is a straightforward, sustainable solution for insulating timber suspended floors. It is easy to install and backed by strong environmental credentials.

Terra Lana’s Drop-in Floor Insulation is the first BRANZ-appraised, high-performance, semi-rigid fibrous insulation in New Zealand, designed for installation before sheet flooring is laid.

Unlike traditional installation methods that compress the insulation for fixing – reducing their effectiveness – our patented system is installed from above, before the flooring is laid. This method maintains full loft and thickness between joists, ensuring consistent thermal performance without compression or gaps. It also allows builders to work from above rather than crawling under the house, making installation faster and easier.

This wool-based insulation has been durability-tested, including BRANZ saturation testing, confirming it can drain and recover if exposed to wet weather during construction. It also comes with a two-week exposure warranty from the manufacturer, offering peace of mind during the build. Standard R2.7 and R3.2 options are available, with custom R-values, thicknesses and widths for orders over 50sqm.

An alternative to polystyrene insulation

For architects aiming to reduce polystyrene use, this is a practical, eco-friendly alternative that eliminates micro-bead waste while improving thermal performance. It also supports sustainability across the site, with a recycling programme available for insulation offcuts.

3D model in WorkingSpec

To make specification simpler, explore our WorkingSpec modelling tool – an interactive, animated 3D model designed to enhance understanding of product assembly using real product data. The tool draws on verified R-values, which helps ensure accuracy when selecting and specifying insulation.

This means clearer communication of design details and gives builders and contractors a more intuitive, visual guide than traditional 2D drawings, improving construction quality and efficiency.

Declare & Eco Choice Aotearoa certified

In 2025, we achieved Eco Choice Aotearoa certification across our entire range of Terra Lana insulation and landscaping products. This trusted label recognises our commitment to sustainability – from materials and manufacturing to packaging and end-of-life. Together with our Declare label, it gives architects and specifiers independent assurance that Terra Lana is a safe, high-performing and environmentally responsible choice for Green Star and Homestar projects.