Frequently asked questions


Dear prospective customer,


In the following we will answer frequently asked questions and provide you with important information regarding the different systems. Please do not hesitate to contact us with any questions you may have.



When did the electro-physical dehumidification of walls first become known?


The basic principles were discovered in 1806 by Professor Reuss. Similar principles are employed in medicine (dialysis), automotive technology (electroplating) and other areas of everyday life. Swiss physicist Paul Ernst registered a patent in 1935.


Has the technology seen further development?


It has indeed. Earlier methods involved the installation of wires in the brickwork. This required structural measures and needed renewing from time to time. Today's EDS systems from Extracom work contact-free, maintenance-free and without structural measures.


Where are EDS (Electronic Dry System) systems from Extracom used?


Basically in any type of building with rising damp. Mainly in older buildings with or without cellars, in single family homes and apartment buildings, holiday homes, hospitals and office buildings, farmhouses, garages, factories and civil protection buildings, as well as in historic buildings, listed buildings, churches, castles and museums. We can determine whether the problem is related to rising damp on the basis of a free and no-obligation, on-site analysis.


What does the EDS system do?


Our technology replaces defective or non-existing humidity barriers and removes rising and laterally penetrating humidity from stone, concrete, tile and wood walls. It neutralises the capillary effect within the wall and forms a kind of protective barrier around the building shell. This means that humidity is no longer able to penetrate and rise in the walls. The humidity in the wall seeps back into the ground. The dry walls regain their original insulating values.


Are there any conditions under which the system does not work?


There are various types of damp in buildings. An exact analysis is strongly recommendable; we provide an analysis free of charge to provide both you and ourselves with the necessary certainty. You can obtain more detailed information in a meeting face to face, from our brochure or from the website under Areas of Application


What can be achieved with the EDS system?


Our systems remove the cause of crumbling paint and plaster, wall erosion, fustiness, mould formation, salt efflorescence and black stains on walls. Elevated ambient humidity is lowered, thus reducing associated health risks such as allergies, colds, rheumatism, etc. Accompanying measures are often recommendable. We frequently receive calls from customers after just a few weeks telling us that the unpleasant musty smell of mould has disappeared.


How long does the drying process take?


The drying process depends on the prevailing conditions in your building (wall thickness, age, degree of moisture penetration, etc.) and environmental conditions such as location and subsurface. Around 80% of all buildings dry enough for any desired renovation work to be carried out after approximately 6 months.


What can accelerate the drying process?


Very good room ventilation or an air dehumidifier, a drainage system or the removal of old paint and plaster layers can help speed up the drying process significantly. These accompanying measures should always be implemented.


When is it not possible to use the system?


Whenever the problem is not due to capillary humidity.


Are you uncertain whether our system will work in your building?


No problem - just contact us and we will clarify it for you. Uncomplicated, professionally and free of charge.


Does the device require maintenance?


Our systems are maintenance-free.


Where are EDS systems installed?


As close to the centre of the building area as possible. Intermediate walls, doors and floors do not impede the effect. Different systems are used depending on the size of the building. A number of systems may be installed in very large buildings.


What are the advantages of the Extracom EDS system in comparison to other methods of drying walls?


Our system does not require any structural measures. In other words: no noise, no dirt, no dust. We do without chemicals and do not generate any electro-smog or noise.


How long is the system's lifetime?


Our systems are manufactured according to very strict specifications and are subject to certified production control. The first generation of devices is still in use after eighteen years. The anticipated lifetime is 20 to 30 years.


How long does a consultation and subsequent installation take?


A consultation will usually last for around one hour. We will provide you with professional information on all aspects of the moisture affecting your building and perform various measurements during the analysis. The installation takes around two hours and includes the compilation of a joint report and humidity measurements at various measurement locations.


What are the anticipated costs and what do they include?


The cost framework for an average single family dwelling is between 5,000 and 6,000 CHF. The price includes the system, installation, measuring point determination and 3 measurements including written reports at 6-monthly intervals - a 100% guarantee for success. There are no additional costs.


What should I look out for when comparing suppliers?


There are always some black sheep in any line of business. Here are some recommendations you should consider in addition to the price.



  • Ask the supplier to open the system. You can only assess differences in quality if you can see inside the devices.
  • What does the quote for your services include? Is it prepared in writing? We will give you a 100% success or money-back guarantee once we are convinced our system will complete the job successfully! If the system proves unsuccessful you will receive a complete refund with no deductions whatsoever, as you would from the majority of our competitors. That is our understanding of a guarantee for success!
  • Demand concrete results with regard to wall moisture and differentiate between excess moisture (capillary) and equilibrium moisture content (EMC) of the material.
  • Demand and check the certificates for the systems. Statements such as CE compliant are not certifications!
  • Enquire how measurements are made (measurement devices with recommended measurement sleeves) and at what intervals.
  • Passive systems (without electricity) are not successful at every location. Additionally, they can extend the drying process by a significant time factor.
  • Is the salesman pushing to close the sale? An investment needs careful consideration - do not allow yourself to be rushed.
  • Can the provider present an extensive and well-maintained list of references? Enquire about the services provided by the company.