Although aesthetic, old field stone houses can experience problems with their foundation.
The foundations of Quebec buildings made of field stone
In Quebec, there are many dry stone houses on wooden piles built from the beginning of the 18th century until the end of the 19th century. Using field stone, these buildings continue to dress the landscape today. Montreal and Ottawa foundations are known for this.
This limestone stone is permeable to water but crumbled by frost, especially when the walls are exposed to the northeast wind. This is why the plaster has been used a lot to protect and optimize the physical rendering of these stone walls. The plaster improves the texture of the wall in case some stones are not well cut and forms a barrier against the weather.
The role of foundations
While some buildings are built on wooden piles or dry stones, field stone houses are usually built on foundations, mostly concrete. The stability of the foundations is very important. They may tend to weaken due to water infiltration or soil quality. This is why it is essential to inspect the foundations regularly in order to preserve them in the best way possible.
However, if you see real problems on your walls, it is essential to use building professionals. Indeed, the quality of the foundations is imperative and a degradation could lead to moisture problems with a health risk to the inhabitants or worse the irreversible degradation of the building.
How to check the good condition of the foundations on stone wall of fields?
In order to keep the foundations of his stone house in optimal condition, it is important to check their condition. Here are some of the problems that may arise, and how to address them:
Check for water infiltration
This type of wet upwelling in the walls can occur in case of heavy rain or snowmelt. There is then a drainage problem at the foundation level. In this case, they must be excavated and a new drainage should be put in place corresponding to the type of soil. Highly recommended, it will even be necessary to install a waterproofing membrane with the new French drain. It is also important to ensure that runoff (particularly gutter water) is away from the foundation.
Problem in the concrete of the foundations
Cracks in the exterior or interior of the building walls can reveal several types of problems. These malfunctions can be found in the masonry or concrete of the foundations: break, sagging or swelling.
There are several possible causes:
- Underground work in the vicinity that can cause soil to shift
- Vibrations due to heavy-duty traffic
- Freezing and thawing
- Strong temperature variations
All these elements make the ground “move. In this case, the foundations should be excavated in order to stabilize and repair them.
Traces of moisture on the walls
Traces of moisture cause fungi and moulds that are dangerous to the health of the inhabitants. Moisture can also cause the mortar to degrade the masonry or cause the floor joists to rot.
The solution is to properly ventilate the crawl space, cellar or basement, especially during the summer. For this to be effective, sighs are required in good condition and good ventilation. Alternatively, it is also possible to set up an air exchanger or dehumidifier.
If you notice a crumbling mortar or damage to the joints that bind the stones and mortar, you should act quickly to prevent any damage to the foundations. The old cladding must then be removed and the joints re-made with a new mortar to repair the cracks.
Maintaining its walls of field stone foundations
From a technical point of view, the maintenance of stone walls is generally not very restrictive if it is carried out on a regular basis. The condition of the mortar joints is to be checked every five years. If the masonry is covered with plaster, small cracks on the surface must be regularly checked and repaired.
From an aesthetic point of view, it is possible to give your stone walls a color similar to the old mortars by adding, on the surface, a coating of lime. Indeed, the colour of mortars and plaster depends on the colour of the sand used and the proportion of lime added. It is therefore possible to change the colour by putting more lime in it.
For a reliable diagnosis of your field stone home, contact our foundation expert who will make a free and personalized submission.