Mick's Notes
Tech-Dry® Plasticure is a rammed earth builder's secret ingredient. Plasticure is a water-based silicone admixture incorporated during the production/mixing process that waterproofs the wall throughout and for its lifetime (needing a minimum of 3% cement). We don’t build without it.
Plasticure helps prevent efflorescence (leaching of salts), mold or mildew staining, rising damp issues, and the need for a damp-proof course (DPC) on your stem wall or footing. This product will make the whole structure water- and salt-resistant, both internally and externally so there’s no need for messy, expensive post-construction surface sealers that require regular applications.
*Please note, some jurisdictions may still call out for a DPC. Please check your local building regulations.
Plasticure reacts with the cement in the mix and becomes a permanent part of the concrete matrix within the structure meaning it can't be washed out or deteriorate due to age for the life of the rammed earth. It’ll also increase the binding of the mix. This product won’t affect the surface breathability, texture or appearance.
This photo demonstrates how water has pooled above our Plasticure treated rammed earth wall after heavy rain.
Please see Aussie Built's Rammed Earth Sealing Process for superior wall construction and presentation.
Description
Tech-Dry® Plasticure is an innovative water-repellent silicone admixture designed to be incorporated in the manufacture of stabilized earth products, including stabilized earth building materials and rammed earth walls containing cement.
When added, it will make the rammed earth products permanently water-repellent, salt, and mold-resistant, and will strengthen the substrate. This product will allow the structure to impart excellent water repellency, both internally and externally, providing long-term resistance against weathering and deterioration. Post-construction surface treatments are generally not required.
Some of the features of Plasticure include:
- Reduces water absorption and efflorescence by over 80%.
- The product remains permanently bonded to the substrate and cannot be washed out.
- Doesn’t leave an oily residue on the masonry substrate.
- Easy to use in any existing process.
- The degree of water resistance can be varied by changing the rate of addition.
- Water-based technology with no hazardous material emitted during use.
For additional information on Plasticure performance and case studies please see this book excerpt from Modern Earth Buildings: Integral Admixtures & Surface Treatments - Modern Earth Buildings.
Dosage
It’s important that the applicator should perform trials before application.
The rate of addition depends on the specific mix design and the level of water repellency required. The usual dosage rate is approximately 5 gallons (20lt) of Plasticure per 40 metric tons of rammed earth dry mix or roughly 5 gallons (20lt) per 700 cubic feet or roughly 1 cup per 8.5 cubic feet of finished wall.
Alternative usage rate: 1 cup of Plasticure per ⅓ yd skid steer bucket mix.
Instructions
Plasticure is designed to be added as part of the gauging water during the mixing process.
- Using a ⅓ yd rammed earth batch mixer, wet and thoroughly mix all the rammed earth dry ingredients.
- Add a minimum of 3% cement to the batch mixer.
- Stir or mix Plasticure before use.
- Measure out 1 cup of Plasticure and dilute it with 1 gallon of clean water.
- Slowly add or spray the above Plasticure dilution into the mix while blending.
- Blend the mix thoroughly while adding clean water to attain the desired consistency. The mix can now be processed as usual.
If your process is substantially different from that described above, please do not hesitate to contact us at info@aussiebuilt.co for assistance.