Mistakes are a part of our lives that we are constantly learning from. There are stages during the construction of a house, such as the insulation of the foundation, where mistakes must be avoided.
Foundations are the foundation of our house. Without foundations the walls could not be built, without foundations we could not create a basement under our first floor, foundations are the most important part of our building. We can distinguish their main two types: traditional foundations – based on footings and foundation walls, and foundation slabs – a flat concrete slab under the entire surface of our building. It is worth reading about the differences between the two types in the material in which we try to solve the puzzle of which is the better choice.
However, a very important issue, already having chosen our foundations, is how we will insulate them. Insulating the foundations is an important part of our groundwork, which will later determine whether problems arise. What if you insulate the foundations badly?
Mistakes when insulating foundations
We can divide mistakes when insulating foundations into two most significant and common ones: in the choice of materials and in the execution.
Errors in the selection of materials
Using ordinary films for insulation
Ordinary plastic insulation films are too thin to shield our foundations from water. They are prone to deterioration and degradation, which will result in dampness in our walls. Polyvinyl chloride flat films and PE films are used for insulation. However, the most commonly used are bucket films, which insulate the foundations vertically. The thicker the film, the more expensive, but more durable.
A complete lack of vertical insulation will result in damp masonry on the footings. A rigid film for the foundation is a guarantee that the waterproofing of the foundation will be done properly.
Inadequate selection of materials
We cannot combine polystyrene with solvent compound. Over time, when these components are combined, the thermal insulation layer will disappear. It is worth using masses that do not contain solvent in their composition, or stick polystyrene on adhesive mortar. Choosing the right type of material is of great importance.
Inadequate selection of materials can result in capillary rise. This is a phenomenon when water is pulled upward against gravity, and through the lack of proper damp proofing. Narrow spaces or porous material makes capillary rise occur. In the worst case scenario, there can be dampness in the walls of the first floor and even the first floor.
Using mineral wool to insulate foundations
Mineral wool has low mechanical strength, although good thermal insulation values. However, wool will deteriorate over time, and our insulation will become hollow like a sieve.
This mistake is rarely encountered, but there are situations when an inexperienced owner sets about working on the foundation on his own. The use of mineral wool in direct contact with the ground misses the point. Even when protecting it with an insulation film, the moisture is high enough that the wool will degrade over time.
Errors in execution
Improper surface preparation
Before laying tar paper, for example, our foundations should be thoroughly cleaned of dust, dirt or other debris. Failure to prepare the surface will result in poorer adhesion of insulation materials.
Before applying insulation layers, the surface must be completely cleaned. Fine particles can reduce the adhesion especially of waterproofing compounds, membranes or bituminous mortars, organic and mineral contaminants can cause uneven distribution of the foundation insulation layer. If we are renovating our house let’s also remove remnants of old paint, plaster or concrete.
Cracks and scratches, cavities in the concrete or protruding pieces of reinforcement. These are elements that should be removed to improve the effectiveness of the insulation.
Lack of vertical insulation along the entire perimeter of the house
There are situations in which we do not have a basement for the entire area of our house. Then comes the idea to save on insulation and protect only the part where the basement is located. This is a big mistake. It is very important to insulate the entire contour of the house. Water will always find an outlet, it will bypass our bubble wrap and get into our foundation, or worse, into the basement.
Moisture insulation too low
We cannot allow our foundation insulation to be brought out too low. Water can go under our insulation layer, which will cause the foundation walls to become damp and water to enter the eventual basement. It is necessary to “extend” the insulation high enough, it is estimated that the minimum is 30 cm above ground level.
Slots
Poor connection of vertical foundation insulation leads to moisture penetration. Just like the lack of insulation along the entire perimeter of the house, so here, we must pay attention to prevent gaps between insulation joints. KMB compounds can help with this.
For proper waterproofing of foundations, our foundation walls must be compacted and whole, so that water does not have the opportunity to find its “entrance to the house.” Leaks also cause capillary rise, which we have already mentioned. In such a case, even properly executed horizontal insulation may not help us.
What if the foundation insulation is poorly done?
Poorly insulated foundations will result in up to a number of serious problems with the building.
moisture inside the building
Moisture that can seep through our foundations into the building will lead to mold, fungus and promote bacterial growth. Foundation walls that are soggy can lead to serious health risks for residents, causing allergies, respiratory problems or skin irritation.
Poor foundation insulation results in increased moisture in the air, thus reducing our thermal comfort, which will lead to higher heating costs.
damage to the building structure
Water entering the foundations as a result of our mistakes will promote corrosion of metal structural elements and degradation of the foundations This will weaken our structure, lead to cracks, deformation and even, in the most extreme cases, threaten the stability of the building.
Concrete that has soaked up water will be prone to micro-cracks in winter. As the water freezes, it expands, which, without foundation insulation, can turn into more damage.
Foundation walls that have cracks will absorb water faster, further accelerating the degradation process. Corrosion of metal components, such as reinforcement in foundation walls, weakens the entire building structure, increasing the risk of deformation, cracks in walls and other load-bearing elements.
appearing water in the basement
Poorly insulated foundations will result in water entering basements or other rooms below the ground. The example below shows an extreme case where the foundations were poorly insulated and water during rainfall entered and created a “spring” that filled the basement with rainwater.
The constant presence of water leads to unpleasant odors, corrosion of installations that are located in the basement. Water supply or heating pipes exposed to constant external contact with water will deteriorate over time.
How to avoid poorly insulated foundations?
It is best to avoid the mistakes mentioned above. But the easiest way is to take advantage of the expertise of the team of Energetic Design, which builds houses from a to z. This way we can be sure that our foundations will be insulated with properly selected materials, and the protection itself will be done according to the art.
When we undertake the construction of a house it is worth betting on a general contractor. Referring to the foundations – for several reasons. One company will coordinate all stages, from excavation, reinforcement and concrete pouring to foundation insulation. In construction, any mistake can have consequences in the future that will be hard to fix.
