Portland Content
Vivus Dry lime Materials
- ·100% natural and recyclable
- ·Quick-setting – (15 minutes and 75% strength after 24 hours).
- ·60%-80% decrease in the CO2 footprint from its manufacture
- Lower environmental footprint
- Just add water. No other materials should be added.
- Humidity Control/ Breathable; it will hold and release air and water allowing a building to “breathe” significantly reducing damp, water ingress and humidity issues leading to mould / fungal problems (unlike Portland cement)
- Strength! Vivus Materials have the “right” strength whether brick, block or stone, but will not exceed that of the material around it which can cause significant issues (spalling/cracks or holes) unlike Portland cement.
- Vivus does not stress the material around it. The proof is in the castles and cathedrals you see to this day which do not use Portland cement.
Gypsum or Vivus Dry lime plasters :
- Gypsum contains sulphates which may irritate lungs and worsen asthma. Cement-based products and gypsum plasters, are hard, inflexible and non-breathable, traditional lime and clay formulas have a soft, characterful appearance, offer a degree of flexibility and are breathable. Gypsum dissolves in water.
- Gypsum is composed of calcium sulphate (CaSO4) and water (H2O). Its chemical name is calcium sulphate dihydrate (CaSO4.2H2O).
- Plasterboard makes up 15% of demolition and construction waste, leaches toxins and releases hydrogen sulphide gas in landfills.
- Virtually ubiquitous in our buildings, gypsum board is widely seen as an innocuous building material. However, in the last decade, Chinese Drywall has been linked with indoor air quality problems, while concerns have cropped up around waste from coal power plants and its links to drywall. buildinggreen.com
- From an emissions standpoint, however, the drywall industry still has a way to go. Approximately 1 percent of U.S. energy emissions come from the production of drywall [Source: Sassoon]
- Domestic manufacturers are quick to point out that gypsum board manufactured in the U.K has not been linked to indoor air quality problems, but potential leaching of heavy metals and biocides included for mould resistance are among the issues that need to be addressed more thoroughly by the gypsum board industry.
- Synthetic gypsum and mercury synthetic gypsum is created from a by product of flue-gas desulfurization (FGD), a process coal-fired power plants use to limit emissions. Although the chemical process that captures FGD gypsum is different from the physical collection of fly ash and bottom ash, which is more likely to pick up heavy metals as a matter of course, mercury and other heavy metals are showing up in synthetic gypsum–and, as a result, in our buildings.
- In 2010, the U.S. Environmental Protection Agency (EPA) released a study of total content and leaching values of heavy metals in synthetic gypsum, which found that these chemicals could have leaching values of up to 550 times the level for safe drinking water. Gypsum becomes poisonous gas in the landfill. However, when drywall reaches landfills–and it does so in vast quantities, as it constitutes about 15% of all construction and demolition debris–it can leach these toxic chemicals into groundwater. And in the anaerobic conditions of landfills, bacteria convert gypsum into hydrogen sulphide, a poisonous gas.
- Unfortunately, post-consumer gypsum board is commonly diverted from landfills to be used as a soil amendment in agricultural settings. If we have restrictions to prevent these toxic chemicals and heavy metals from being spewed into the air by power plants, is it really a good idea to add them straight into our soil? buildinggreen.com Gypsum Board: Are Our Walls Leaching Toxins ? March 14, 2012
- The global Lime and Gypsum Product Manufacturing market was valued at $238.6 billion in 2017. Asia Pacific was the largest geographic region accounting for $156.8 billion or 65.7% of the global market. And China was the largest country accounting for $94.4 billion or 39.5% of the global Lime and Gypsum Product Manufacturing market.
- Vivus Solutions vs Gypsum Conclusion
- Lime does not produce and noxious gas,
- Vivus lime is not deliquescent
- Vivus does not dissolve with future wetting, once set, that’s how it stays.
- Lime is Breathability, Gypsum is not. Breathability is not really about air . It is about water, water as a gas and water as a liquid; water inside the building, water outside the building, and water in the walls, floors and roofs. It is not only about how water moves through structures (water vapour permeability), but also about the ability of materials to absorb and release water as vapour (hygroscopicity) and about the ability of materials to absorb and release water as liquid (capillarity). Water affects everything in building from the health or decay of building fabric, through to the thermal performance of the building and to the health of occupants. Particularly as we try to increase the airtightness, thermal performance and indoor air quality of our buildings, breathability has become a critical issue, affecting all areas both of new build and of renovation. – Vivus Materials have a positive effect on all these elements.
Hot-mixed mortars: the new lime revival. Alison Henry Head of Building Conservation & Research Team, Historic England.
See link below for full article.
Hydraulic Lime and NHLs
“Before exploring the pros and cons of hot-mixed mortars, it is worth reflecting on the past 40 years of lime use and how we have arrived at the current situation. . Quicklime made in traditional kilns often contained under- or over burned limestone which did not slake when the mortar was made, and remained in the mix as rounded whitish particles, often referred to as ‘lime lumps’. Fragments of black fuel ash from the lime kiln sometimes found their way into the mortar too. These are clearly visible in many hot-mixed mortars. However, for very high quality work, quicklime was ‘BHP’ – ‘best hand-picked’ – and did not contain lime lumps or ash. The lime revival As the damage caused by hard, impervious cement mortars became apparent from the mid- 20th century, the revival in use of lime from the 1970s was naturally welcomed by conservation practitioners. Emerging practice borrowed from materials and methods used in various stonework conservation programmes, particularly the restoration of the west front at Wells Cathedral from 1974. Here non-hydraulic lime putty, typically blended in a ratio of 1:3 with aggregates, was used to make sacrificial mortars for conservation of fragile limestone sculpture; pozzolans were added where additional strength was needed. Mortar design was based on practical experiment, and ignored historic source materials. While such mortars were eminently suitable for this specialist application, and proved durable for re-pointing and rendering in sheltered locations, there were some failures when they were used in more exposed locations. During the 1990s attention began to shift towards hydraulic lime, which it was hoped would prove more durable. Hydraulic lime began to be imported from the continent and there was a brief renaissance of production in the UK. Mixes generally comprised 1 part powdered lime to 2 or 2½ parts aggregate. These mortars were indeed faster-setting and more resistant to salt and frost damage than ones made with lime putty. However, by the early 21st century alarm bells were ringing in some quarters. Many practitioners were concerned that the new breeds of hydraulic limes (termed natural hydraulic limes [NHLs] under the relevant standard) were much stronger than their historic counterparts, and were perhaps too strong for many conservation applications. Comparison of the compressive strength of mortars made with NHLs with that of the limes most widely used historically (non-hydraulic and ‘feebly hydraulic’ lime) reveals clear differences, and suggests that concern about excessive strength of NHL mortars might be well founded. Further concerns about long-term strength gain were raised by recent research commissioned by Historic England¹. Furthermore, historic records and analysis of mortars indicate that in the past the stronger grades of hydraulic lime (termed ‘moderately’ and ‘eminently hydraulic’), which compare closely in strength to the modern NHLs, were reserved for high-strength applications such as military and civil works, and for work underwater or in persistently wet environments. Yet by the early 21st century NHL mortars were being widely specified for many conservation applications, sometimes even for internal plastering.
historicengland.org.uk/content/docs/research/ctx154-henry-hot-mixed-mortarspdf/