L is for Listed Buildings and the use of Electro Osmosis.
In this instalment of A-Z of Atlantis Damp Proofing & Timber Specialists, L is for Listed Buildings and the use of Electro Osmosis.
Today we went to survey a beautiful sandstone cottage in Tarporley, Cheshire and noticed a very old Electro Osmosis damp proof system in place. It got us to thinking. When would we recommend an Electro-osmosis system to be installed?
Although we strongly recommend the use of Dryzone thixotropic chemical DPC for the vast majority of our damp proofing remedial works, occasionally there comes a time when cream installation is not appropriate. For example, on an English Heritage site. Often it is a condition of any remedial works that the building must be able to be returned to their original condition. Once the thixotropic cream has cured to form a water resistant barrier along the mortar course, it can not be removed. This is where Electro Osmosis Damp proofing system may be utilised.
What is Electro Osmosis?
Electro-osmosis involves the introduction of a low static electrical charge into the masonry, via a series of titanium wire anodes. A series of holes are drilled into the mortar course. The anodes are inserted into these holes at the base of the walls (at the same height as a chemical DPC). The anodes are then linked by a thin wire, creating the circuit. It is then connected to a mains electrical circuit via a small transformer. The volts are very low and perfectly safe. The theory is that the positive charge through the wire repels the rising moisture molecules, thus preventing damp from rising.
What are the benefits of this system?
- Installation is neat and quick.
- The complete circuit is virtually invisible and the disruption is minimal.
- It is chemical free and environmentally friendly. Again, this can sometimes be a key consideration for some customers. Listed building or not.
- The system operates well in all types of masonry (brick, stone composite walls and concrete).
- Energy consumption remains negligibly low.
Which Electro Osmosis system do we use?
- Our anodes are pure titanium coated with a platinum group element. This ensures outstanding reliability and resistance to physical and chemical attack.
- We use titanium wire.
- All modern Electro Osmosis circuits are earthed for your safety.
Why doesn’t Atlantis Damp proofing & Timber Specialists routinely recommend this damp proofing system?
There are two main reasons that we choose not to routinely recommend the Electro Osmosis system. Firstly, it does not have BBA approval. Only products and systems that have passed a series of comprehensive assessments – including laboratory tests, on-site evaluations, quality management checks and inspections of production are awarded an Agrément Certificate. This is BBA Approval. Dryzone has BBA approval. This, coupled with the excellent product performance we have seen ourselves over the past decade, means it’s remains our first choice.
Secondly, Electro Osmosis systems provide no solution to salt contaminated walls. See our blog on hygroscopic salts to understand why we believe this is the second half of any good solution to tackle rising damp.
So in spite of the fact that we believe that Electro Osmosis may have a place in today’s Damp Proofing industry, we will not be recommending it to solve the damp issues in the sandstone cottage we saw today. Despite the non-standard construction of the property in Tarporley, Cheshire, we believe Dryzone thixotropic cream will be the most effective solution.
Are you unsure of the best option to treat your property’s rising damp issue? Contact us today to talk it through or arrange a site visit so we can explain t he best option to you.