Rammed Earth is hailed as the most environmentally friendly building material available today. The principle that you can build a structure from readily available resources on site – earth and clay, is an obvious way to cover the environmental impact of your new build.
As New Zealand’s leading Rammed Earth Construction Company, Terra Firma has built up years of experience in the techniques involved in working with rammed earth. Its clear how rammed earth can be used as a safe, low cost, non-toxic building material however we also recognize the function and finishing of a home as being a primary objective for our clients.
Whilst we build new homes’ walls using rammed earth, incorporating rammed earth floors is very costly in a new build. Rammed Earth Flooring as a technology had been used for hundreds of years however the research and development in modernizing the technology is still in its infancy.
Construction of Rammed Earth Floors takes a lot of time, is very labour intensive and has been seen to fall short of the high standard of quality Terra Firma assures its clients. Rammed Earth Floors also require ongoing maintenance, which many homeowners do not wish to be carrying out themselves. Whilst the principle of using rammed earth for flooring is sound, in a commercial operation it is often too costly and can provide an unacceptable standard of finish.
Currently we would recommend rammed earth flooring projects to be undertaken by keen DIY builders who have time and are interested in experimenting on a renovation project.
Concrete Floor With Enhanced Finish
At Terra Firma we install concrete floors that are cut and grouted to give a tile like finish. This solution provides the home with an excellent thermal mass, is cost effective and is a very durable and low maintenance flooring material.
For this system of concrete floor we apply several coats of Tung oil just prior to completion of house construction (maximum drying/curing time for concrete). Tung oil provides a clean, non-slip surface finish, which, importantly, allows the concrete to breathe. We also use Iron oxide dyes in the concrete laying stage to create specific floor colourings depending on client specifications.
Poured Earth Tiles
An alternative to the problematic installation of a rammed earth floor is to create and lay poured earth tiles, still more costly than an enhanced finish concrete floor but far more likely to provide an appropriate specification and still maintain the softer richer feel of an earth floor.
Poured Earth Tiles are constructed several months before the expected installation, as they need to cure before use, the general procedure is as follows:
- Extract and sift earth from local site, earth must have some clay content.
- Sifted earth is mixed with 20 – 25 % concrete and polypropylene fibers.
- The mix is poured into 400mm x 600mm tile dividers constructed from non-stick form ply and using a layer of Vaseline as a release agent.
- The tiles are left to dry in the formwork for 36 hours to prevent cracking or twisting, then finished with ‘Tung Oil’ and stacked in a shaded area to cure for 2 months before installation.
- Tiles are laid on a bed of reasonably dry mortar, each tile up to 25 – 30mm apart. We use wide grout lines so that a basic sand and cement mixture is sufficient enough to stop any cracking whilst keeping free of toxic materials.
- As with an enhanced concrete floor we use Tung oil as a water resistant, non-slip, easy clean and breathing surface coating.
For further information on constructing your home using Rammed Earth contact Terra Firma on +64 (09) 963 5942.