Extracts Accumulated Salts
Water and paper based accumulated salt extraction treatment
We are the UK sub-distributor of Westox Nordic. The Australian based parent company Westox Building Products www.westox.com are leaders in the field of desalination and salt contamination removal, involved in the restoration of World Famous Heritage Buildings.
Historically in the UK we have been behind the curve with regards to salt damp/salt attack, however we now have Westox Cocoon to combat this problem. Westox Cocoon poultice is an innovative breakthrough desalination product designed to remove accumulated corrosive salt from masonry of all types including sandstone, concrete and brickwork. This is a world patented water based, non-toxic, 100% environmentally friendly, non-destructive repair system providing a cost-efficient method for addressing issues like:
- Salt damp and salt attack on traditional sandstone and masonry structures
- Rising Damp
- Reinforced concrete slab degradation, Concrete Cancer and Spalling
Salt Damp and Salt Attack on Traditional Sandstone and Masonry Structures
Sandstone is the main type of stone used in Scotland for building purposes. Sandstone is naturally porous and prone to erosion from external and internal elements. The most significant factor that affects the natural durability of stone is its pore structure. Pore structure is significant because it involves the amount of water entering and moving through the stone. Corrosive salts migrate by the water and when evaporation occurs these accumulated salts will crystallise within the pores exerting pressure which results in damage to the stone. The potential for further damage is accelerated by the capillary ascending moisture or Rising Damp. The repetitive nature of the re-dissolving and re-crystallising of corrosive salts tends to result in exfoliation to the stone and inevitably salt damp/salt attack will damage the stone. See this video on how Westox Cocoon Works.
Interstitial condensation is also a form of dampness linked to Hygroscopic salts, such as chlorides/nitrates, and sometimes Deliquescent salts that are present in the stone structure. They absorb water from the air, when its humid, causing further damage to the stone structure. We have serious concerns that world climate change is also impacting the wider built environment. Our older properties are under pressure to be upgraded to meet the Governments energy efficiency commitments. This ultimately is resulting in an increased relative humidity in our homes where the hygroscopic salts are absorbing the excessive moisture and causing serious salt damp issues. We recommend you act now as “Prevention is better than cure”. Work with us and “Breath life back into our older buildings”.
We have recognised the United Kingdom is now in need of immediate intervention and according to Conservation Science our traditional built properties are in the danger zone for serious salt attack/decay.
Our intervention, Westox Cocoon, will reverse the decay bringing your building back to a world recognised “safe salt level”. Then, by adopting a holistic approach to the future maintenance and the use of traditional materials will result in a cost-effective preservation approach to the buildings restoration.
We are fully aware of the controversy in the UK around rising damp and whether it really exists. The confusion is simply down to the misdiagnoses of the source of dampness. The truth is that rising damp does exist, but it is regularly confused with condensation and other forms of penetrating dampness. Our team of professionals are fully trained to identify the difference and correctly diagnose all forms of remedial repairs.
Our work methodology is to initially undertake a full damp survey and collect samples for laboratory Ion Chromatography testing. The laboratory results will assist us to formulate a sympathetic remedial plan for your property.
Reinforced concrete slab degradation, Concrete Cancer and Spalling
Our sister company Neoferma is the world leader in utilising Westox Cocoon as an innovative desalination product to remove the corrosive salts from concrete in both the construction and civil engineering industries. This methodology provides a cost-efficient approach to combating the degradation of the steel reinforcing. The high pH alkalinity of concrete forms a passive film on the surface of steel reinforcing that helps prevent or minimise corrosion. Carbonation and the ingress of chlorides (salt) causes erosion to the concrete’s structural durability, reducing the pH of carbonated concrete to a level below the passivation threshold of steel.
The use of Westox Cocoon helps to combat the problem resulting in improvements to the concrete properties such as chloride/carbonation resistance and freeze thaw. Our process provides an alternative to Electrochemical Chloride Extraction as our desalination process is sympathetic to the concrete and avoids the need to expose the steel reinforcing/concrete to high voltages which can cause reduction to the bond strength.
Efflorescence (which means "to flower out" in French) is a crystalline deposit of salts that migrate to the surfaces of masonry or concrete and is white in appearance. The process involves the dissolving of an internally held salt in water, or occasionally in another solvent. The water, with the salt now held in solution, migrates to the surface, then evaporates, leaving a coating of the salt.
On Sandstone, brick or concrete, efflorescence may present a cosmetic outer problem only (primary efflorescence causing staining), but it could be an indication of internal structural weakness (migration/degradation of component materials). Efflorescence will clog the pores of porous materials, resulting in the destruction of those materials by internal water pressure.
The mechanics by which efflorescing salts are carried to the surface of structures by moisture and capillary action is understood. The amount and character of the material deposited varies depending on the nature and source of the soluble materials.
The phenomenon of cryptoflorescence, sometimes referred to as crypto-efflorescence is a hybrid of the word crypto meaning to lock in and florescence to bloom. The chemistry of the compounds which produce cryptoflorescence are similar to those that produce efflorescence, therefore the formation, behaviour and subsequent results of cryptoflorescence using a chemical analogy with efflorescence is adopted.
Cryptoflorescence is also related to the soluble salt content of the brick, but when the rate of movement of the salt solution through the brick pores is lower than the rate of evaporation, the drying zone may form beneath the surface or at the brick/mortar interface. The subsequent crystallisation of these salts in the pores over time at these locations may lead to an expansion in the masonry.
All Cocoon projects are independently tested using Ion Chromatography testing prior, during and post application. Applied both externally and on occasions internally on the surface, Westox Cocoon draws the accumulated corrosive salt out of the structure protecting it from further degradation.
For suitable applications within 4-6 weeks, traditional sandstone buildings, reinforced concrete slabs and brickwork can be returned to the worldwide accepted “safe salt content level” of 0.2% of total an ion salt by weight.