During the past years we have been monitoring several hundreds of buildings long-term via professional moisture measurements taken at regular intervals. This lead to some very interesting observations about:
- How our dehydration system dries out the building
- How moisture moves inside the building fabric
- What are the main variables that affect the dehydration
- Main limitations, what the system can and can't do etc.
The research is still ongoing, however here is a summary of some of our findings in this regard:
1. Dehydration of Non-Breathable Walls
While traditional buildings have been built moisture permeable (breathable) rather than impermeable as most newer buildings, a lot of repairs on older buildings have been done with modern materials. Here are some of the works which we frequently encounter which negatively affect the drying-out of old buildings:
- cement pointing (instead of lime)
- cement rendering
- modern plaster (cement + gypsum finish)
- wallpaper on top of modern plaster, often painted
- concrete floors
- concrete walkways around the building
- lack of drainage
- etc. etc.
All these factors, a way or other, contribute to the retention of moisture inside the building fabric and the remedy often involves invasive and costly measures (e.g. re-pointing, removing the cement render etc.)
We strongly advocate the use of traditional, building-friendly materials wherever possible, however in certain cases traditional methods can not be implemented, or are too costly or too invasive. We have found that the magnetic DPC system most of the time dries out or significantly improves the condition of such buildings without any of the invasive measures.
Here is an example: a building with cement render, modern plaster, concrete floors and a concrete walkway around it. In other words, from conservation viewpoint, a lot of no-nos. Installing the magnetic DPC system produced a significant change within 6 months without a major building works being done during most of this time.
2. Protection to Floor Joists
Floor joists often start rotting because the masonry is damp. By dehydrating the building down to the solum level, floors joists will often benefit from it and their decay stops.
3. Less Crumbling
Ongoing crumbling of the historic building fabric is of major concern as it leads to a gradual irreversible deterioration of the building fabric. Although crumbling can have several reasons, one of the leading causes are ground salts. Ground salts are being transported into the building fabric by rising damp. When the water evaporates, leaves the salts behind which crystallize on or under the surface. During the crystallization process the salts expand in volume several times (typically 5-10X) resulting in the breakdown of the building fabric at capillary level.
Crystallization pressure can generate significant forces. Most of us are aware of the power of water freeing into ice, expanding in volume, which can fracture copper or steel pipes.
The Magnetic DPC system, by stopping the upward transport of water and salts inside the wall capillaries, it will stabilize the building, resulting in less crumbling.
4. Warmer Buildings
Does your building feels cold all or most of the time? Does it take a long time to heat it up or keep it warm? As the building fabric dries out it will gradually regain its thermal insulation. Many customers reported a significant improvement in the internal ambiance of the building, an often important side-benefit of our building dehydration system.
5. Less Condensation & Mould
Condensation is typically not a dampness problem but an insulation problem. Walls cool down and the warm humid air will condense on the cold surfaces, usually on the bottom of the walls or corners. The humidity provides the necessary water for mould to survive and as a result black mould often grows in these areas.
When the building is affected by rising damp, the constant evaporation at the base of the walls cools the walls down even further, resulting in condensation and the appearance of mould. By drying the wall fabric out often will help with the condensation problem as the walls get warmer and thus less subject to condensation.
However the DPC system is not your primary defense mechanism against condensation. There are other more efficient ways to deal with the problem, nevertheless it can help to tackle certain condensation problems.
6. Less Musty Smell
By drying out the building fabric musty smell often reduces considerably or vanishes altogether. This often happens within a few months after the installation of the dehydration system.
Retired architect, cottage owner
7. Better, Healthier Living Environment
Some of our customers report back to us a better, healthier living environment as a result of the walls drying out. We understand that this is a highly subjective observation, however the decrease of moisture and humidity leads to less mould and potentially less pathogens in the building. We do not have the means to assess or verify that, however we are happy to pass on some of the subjective observations of our customers who have been using our dehydration systems for a while.
Country House owner