The best way to protect the foundation of a building is to insulate the foundation of the house from the outside

For your home to last a long time and maintain its structural integrity, you must protect its foundation. Insulating the foundation from the outside is one of the best strategies. In addition to helping to maintain consistent indoor temperatures, this method guards against moisture intrusion, which can result in major problems like mold growth and the degradation of building materials.

Heat loss through the foundation walls is decreased by insulating the foundation from the outside. This can lead to reduced heating costs and increased thermal comfort within the home, particularly in colder climates where these expenses can mount up. It also keeps drafts and cold spots away from the base of your walls, making your home more comfortable all year round.

The ability of external foundation insulation to prevent water damage is a noteworthy additional advantage. Over time, moisture can seep into foundation walls, weakening them and possibly creating structural issues. External insulation serves as a waterproof barrier, diverting water away from the foundation and lowering the possibility of leaks and fractures.

Additionally, adding external insulation to the foundation can increase the overall longevity of your house. It protects the masonry or concrete from freeze-thaw cycles and temperature swings that can cause frost heave. By maintaining the foundation’s structural integrity, this protection helps to increase the building’s overall lifespan.

Why insulate the foundation base from the outside?

Because load-bearing walls and ceilings place the most stress on the base and foundation of a building, these components are thought to be the most vulnerable. Because this portion of the house is underground, it is subject to freezing temperatures and moisture all the time.

Excellent guidance! In order to maximize a structure’s strength and durability—a factor that ultimately determines the building’s service life—the foundation and blind area must be insulated.

The basement is an extension of the foundation that rises above the ground and enters the building’s exterior walls. Stated differently, this portion of the structure serves as a link between the foundation and the load-bearing walls beginning at the first floor level. In addition to providing protection from extreme heat and humidity, the plinth also gives the house a more appealing appearance.

Initially, it is important to remember that insulation materials need to offer complete thermal insulation for the building’s blind area as well as the basement wall. It would be incorrect to discuss the efficacy of such measures in any other situation. It is theoretically possible to insulate the foundation from the outside as well as the inside, but the results will vary depending on which approach works best.

In this situation, condensation will build up in the space between the wall and the insulation, which will negatively impact the walls. Internal waterproofing and insulation of the foundation will help to insulate the room from the penetration of cold. Furthermore, the base won’t be shielded from frost when insulating the foundation from the interior of the home. Consequently, fissures might emerge and gradually widen, leading to a reduction in the building’s strength attributes.

You can prevent freezing in the basement and the material used to make the base by insulating the foundation from the outside. Additionally, the dew point moves toward the insulating material, which is thought to be more resilient to low temperatures and humidity than the base itself. A warmer basement and an extended period of the load-bearing structure’s operation are the outcomes of the work. This kind of work is best done during the building phase. Doing this after construction is finished will make the task much more challenging to finish.

Before insulating a house’s foundation, you should educate yourself on the circumstances in which work may not be required. You can skip this construction stage, for instance, if this is a small country house that will only be used in the summer. Other circumstances in which you can put off doing outside work and stick to floor insulation alone include:

• with a low base – up to 0.5 m;
• It is not always necessary to insulate a shallow foundation;
• if the building is located in favorable climatic conditions with no harsh winters.

Insulating the foundation of a house from the outside: main advantages

In the winter, a large reinforced concrete foundation lacking external thermal insulation will act as a powerful cooling accumulator, causing the surrounding building structures to become colder. Naturally, ground floor rooms have their own insulation in the walls and ceiling and are typically located above the basement. But being so close together always results in excessive heat loss and, with it, higher energy bills for heating. Experience has shown that, under ideal circumstances, the best material to insulate the foundation base can save up to 20–25% of the heat.

Preventing heat leakage from the building is the primary justification for insulating a home’s foundation. Good quality insulation lowers the effects of winter soil swelling almost completely (to 0 ° C) in the blind areas around the house and on the basement walls. The explanation is straightforward: the earth beneath the house and close to the basement does not freeze.

Based on climatic factors, each region has its unique markers of soil freezing depth. Because geothermal heat always rises from below, the temperature remains relatively constant below this threshold. A private home’s base walls won’t be able to prevent the spread of soil freezing if the foundation isn’t insulated. This causes a strip of earth to freeze inside the foundation as well as the upper portion of the foundation itself.

Crucial! The ground and foundation walls are shielded from early destruction from the freezing zone once the house’s foundation is insulated.

Every premium reinforced concrete foundation has a certain level of frost resistance. An appropriately prepared M300 cement mortar, for instance, typically has a frost resistance of F200, meaning it can endure up to 200 cycles of freezing and thawing without losing its essential properties. But one shouldn’t assume that a cycle is equivalent to a year. Given the erratic nature of the autumn or spring weather, several dozen such cycles may transpire in a single season. Consequently, it is advisable to insulate the house’s foundation in order to prevent the effects of temperature fluctuations on the base.

How do they finish the foundation of a private house

When thermal insulation is installed, the freezing zone stays outside the house and stays outside the foundation walls. And there are numerous benefits right away. From the sole to the uppermost section of the basement, the strip foundation will be roughly at the same temperature throughout. This indicates that there won’t be any strong internal stresses in the reinforced concrete structure, which are frequently brought on by substantial thermal disorders. One of the factors contributing to the building’s rapid deterioration is the strip foundation’s lack of insulation.

How can the foundation be insulated? Though technology has advanced over the last few decades, the basement has more recently been heated with a clay mixture mixed with straw. Numerous new thermal insulation materials were created, and they are all distinguished by their practical shapes and simplicity of installation. The following standards must be fulfilled by all contemporary materials:

1. Low thermal conductivity. The lower the thermal conductivity coefficient, the better the thermal insulation properties of the building material.
2. Low water absorption. Insulation that is susceptible to moisture absorption does not fulfill the requirements assigned to it and loses its consumer qualities. This is especially dangerous if the material absorbs moisture in winter, when freezing water disrupts the structure of the sheets.
3. High compressive strength. The soil exerts a lot of pressure on the base, which the insulation must withstand without changing its properties.
4. Resistance to harmful microorganisms. Material susceptible to fungal growth and mold will quickly become unusable. Also, insulation sheets should not be exposed to rodents.

The cost of foundation insulation will vary depending on the conditions under which the work is done and whether it is being done during the construction phase or not. The type of material used has an impact on the cost as well; the primary ones are:

• sprayed insulation – polyurethane foam;
• thermal insulation sheets – polystyrene foam, penoplex, mineral wool, extruded polystyrene foam;
• expanded clay – an inexpensive, bulk type of thermal insulation;
• thermal panels – consist of three layers, including the finishing layer, where plaster or facing tiles are used;
• warm plaster;
• priming.

Insulating your home’s foundation from the outside is the best way to preserve it, which is essential for long-term stability. By using this technique, the foundation is shielded from moisture and temperature changes, which over time can lead to cracks and structural damage. You can improve energy efficiency, lower your heating and cooling expenses, and guarantee the structural longevity of your home by making an investment in exterior foundation insulation.

Insulating the foundation of a house from the outside with polystyrene foam

Polystyrene foam insulation of the foundation is one of the most widely used techniques among builders to keep the base from freezing. Polystyrene foam slabs—which have a higher density and should have a minimum thickness of 5 cm—cover the base and foundation. The following are some of the key benefits of using polystyrene foam for foundation insulation:

• high thermal insulation qualities and optimal thermal conductivity coefficient;
• inability to absorb moisture or degrade when exposed to water due to its closed cell structure;
• long period of operation – over 50 years;
• good sound and noise insulation properties;
• resistance to ignition due to the applied fire retardant;
• no possibility of mold or fungal growth;
• simple and quick installation of sheets, easy processing and the possibility of self-fixing without the use of special tools;
• low cost of material and installation.

It is important to keep in mind that polystyrene foam has a major drawback: it becomes unstable in the presence of rodents, which can harm the sheets. One more drawback is the abundance of joints between sheets. Penoplex, or extruded polystyrene foam, is characterized by a higher density and a smaller thickness, offering a few less drawbacks.

Polystyrene foam is a more effective external insulation for a house’s foundation and blind area than traditional polystyrene foam because of its interlocking joints, which guarantee a more dense arrangement of sheets in relation to one another. Furthermore, the material exhibits reduced fragility, resists crumbling when sliced, and can support heavier loads.

Excellent guidance! Penoplex insulation allows for a thinner layer of insulation to be added to a house’s foundation without sacrificing its ability to retain heat. This enables less depth to be added to the window openings, increasing the amount of natural light that enters the space.

Because of their distinct geometric shapes, extruded polystyrene boards are lightweight, highly resistant to heat transfer, easy to process and install, long-lasting, and environmentally friendly, among many other benefits.

It is relatively simple to determine how much polystyrene foam will be needed when insulating a house’s foundation by hand. This is especially true if you have a building plan that includes the specifications needed for both vertical and horizontal basic insulation. The formula typically uses the standard Penoplex board dimensions (1200 x 600 mm) and the range of insulation thicknesses (in milliliters) of Penoplex F panels designed especially for foundations:

What is foamed polyurethane foam, how is it used to insulate the foundation

DIY Foamed polyurethane foam, which has outstanding consumer qualities, has recently gained popularity for insulating the foundation of already-built homes. The sole drawback is the requirement for a unique setup during application, wherein the polyol and isocyanate are combined under pressure, subsequently initiating the polymer synthesis. Carbon dioxide is produced during the reaction, resulting in separate bubbles. On a base that has been cleaned and ready, spraying is done in a thin layer.

It is advised that you become acquainted with the material’s advantages and disadvantages prior to insulating the foundation:

1. Excellent thermal insulation properties, which are improved due to the presence of carbon dioxide bubbles, because the thermal conductivity coefficient of polyurethane foam is slightly lower than that of air.
2. Resistance to mold and fungal growth.
3. Continuity of the applied layer without gaps, joints, cracks or seams.
4. Light weight, which allows the solution to be used on houses with any type of foundation. At the same time, high strength, rigidity and elasticity.
5. Easy repair. If a certain area is damaged, it can be easily cleaned and filled with a new portion of polymer.
6. Quick application. Spray insulation takes no longer than one day to complete.

The disadvantages include the expensive nature of the material and the incapacity to complete the task on one’s own, in addition to the requirement for specialized tools for application.

How mineral wool and warm plaster are used to insulate the foundation

Although the term "mineral wool" covers a wide variety of building materials, basalt wool is most frequently used as foundation or base insulation. The raw materials are rocks, from which thin threads that serve as the foundation for the insulation are extracted during the heating and melting process. The material is made either in slabs or rolls. In addition, using rolled mineral wool reduces the amount of seams required, but the slabs have more strength. The primary benefits of utilizing the content are:

• optimal thermal conductivity coefficient ensured due to the presence of a fibrous structure;
• good sound insulation;
• low susceptibility to combustion, because the basis is mineral substances;
• high vapor permeability rates;
• increased strength and resistance to mechanical damage;
• resistance to mold, fungi and rodents.

You can quickly and simply insulate a house’s foundation from the outside using mineral wool by hand. It’s not totally accurate, even though a lot of manufacturers mention how the material can pass water and doesn’t absorb moisture. Most of the time, sheets can retain moisture and have much less thermal insulation capacity. Some manufacturers treat their materials with certain water-repellent substances to prevent this kind of situation, but even in these cases, reliable waterproofing is necessary, and that will mean paying extra for installation.

Dry adhesive mixtures that differ from the facing material are used in warm plaster. The most common ingredients in insulation are polystyrene foam, vermiculite, and sawdust. The heat insulator’s monolithic design and easy installation are the primary benefits of the application. As soon as the first layer of primer has dried, warm plaster can be applied. Installation can be completed without the use of reinforcing mesh if two layers are not required, which drastically lowers labor costs. Some of the drawbacks are:

• high level of water absorption, which requires waterproofing;
• a small layer of application, which cannot always provide the proper level of thermal insulation;
• large weight after use;
• the need to cover the finish layer.

Using the foundation of expanded clay and thermal panels for insulation

Expanded clay has a lot of big granules and is regarded as a light material. A light-melting clay that is expanding and solidifying in the drum environment serves as the foundation for the insulation. Keramzit is the least expensive material that is both safe and eco-friendly. ideal for insulating a wooden house’s foundation—one that isn’t meant to house people all year round. The primary benefits of the purchase are:

• good noise and thermal insulation provided due to the porous structure;
• little weight;
• good frost resistance and refractory.

The primary drawback of using it is that it can absorb moisture, which is inappropriate for a foundation or basement. Good waterproofing techniques are used to address this issue, and drainage needs to be set up by excavating a ditch that is deeper than the foundation and placing geotextiles at its bottom. It is covered with a medium-sized crushed stone layer, and a pipe with holes drilled through it allows moisture to drain away.

After that, there are more layers of geotextiles and crushed stone, and finally, sand covers everything. Following completion of the preparatory work, roofing material is laid so as to cover the walls of the building and the ditch, and the seams are taped. Wooden formwork is then installed to the depth of the foundation. A 45° angle-installed lid is placed over the formwork once it has been filled with expanded clay of a heterogeneous fraction. The purpose of doing this is to shield the base from precipitation, especially dew.

Rigid polyurethane foam, the foundation of thermal panels, has many of the same advantages as penoplex. The primary benefit of use is the ornamental top shell, which can mimic any kind of material. The most common materials used for the foundation and ground floor are imitation stone, brick, or tile. You can install the panels yourself because they are fully functional and will only cost you 2,000 rubles per square meter when used to insulate the foundation. Additional advantageous traits:

• moisture resistance and good thermal insulation;
• attractive appearance;
• no risk of mold growth.

The drawbacks include the high cost as well as the requirement for pricey, high-quality adhesive and extra caution when gluing. The base must be perfectly flat in order to glue the panels; otherwise, lathing will need to be installed in addition, but the outcome will be a base that is effectively protected.

Very useful information! Occasionally, regular sand or earth is utilized as a temporary substitute for insulation, filling the base all the way up to the first floor’s floor. It will be necessary to relocate the ventilation holes above ground level, and window installation will not be feasible.

Features of insulation of pile foundations, strip and slab foundations

The technology used for foundation slab insulation is comparable to that used for ground-level concrete floor thermal insulation. This is accomplished by first compacting the soil, and then placing a geomembrane on top of it to shield the foundation from groundwater’s capillary rise. The following layers come next:

• crushed stone-sand cushion, which increases the load-bearing capacity of the soil and correctly distributes the load;
• roll waterproofing;
• insulation, most often used polystyrene foam or penoplex.

There are numerous technologies available to insulate strip foundations. In addition to using penoplex to insulate the outside of the foundation, other methods include finishing with expanded clay, sprayed insulation, and permanent formwork. Because mineral wool absorbs moisture, it is rarely used in this situation.

Since the thermal insulation materials used to insulate the foundation are an integral part of the structure, planning is required if you decide to use the permanent formwork method.

This is fascinating! Two problems are solved at once when permanent formwork is installed: the foundation’s interior and exterior insulation.

Formwork comes in a variety of materials, but expanded polystyrene or penoplex are typically used to insulate the foundation base from the outside. Prior to beginning work, the blind area must be created by excavating a recess from the compacted soil. This recess is then filled in sequentially with the following materials:

• crushed stone;
• sand;
• waterproofing;
• insulation;
• formwork;
• reinforcing layer;
• concrete.

The base’s insulation from pillars or piles is equally crucial. Of course, freezing forces and the destructive effects of soil moisture no longer pose a threat to a properly designed foundation of this kind. Nonetheless, there exist several other equally significant problems that can solely be resolved through the development of thermal insulation.

Thermal insulation for columnar piles or lattices made of reinforced concrete must be at least as thick as the strip’s base. It is crucial to realize that piles are frequently attached to a monolithic grid of reinforced concrete, which turns into a potent refrigeration element in the absence of adequate insulation. A gap between the first floor’s ceiling, where utilities are typically installed, and the ground is a defining characteristic of a foundation on piles.

The most common practice for insulating a wooden house’s pile-screw foundation is to also decorate this area of the facade. Regardless, the area between the house and the ground will be sealed off on all sides to prevent the buildup of dirt or debris. Insulating a pile-screw foundation is also essential to ensuring a comfortable living environment, extending the building’s service life, and enhancing the structure’s aesthetics.

The best approach to protect your home from outside elements and preserve structural integrity is to insulate the foundation from the outside. Direct application of insulation to the external surfaces forms a barrier that protects the foundation from changes in temperature, moisture, and other possible damage sources.

The ability of external foundation insulation to stop moisture infiltration is one of its main advantages. Over time, moisture can penetrate masonry and concrete, resulting in cracks and jeopardizing the stability of the foundation. External insulation lowers the possibility of water intrusion, which is essential for avoiding expensive repairs and preserving a dry, healthy atmosphere within your house.

Additionally, external insulation improves thermal efficiency. It assists in controlling the foundation’s temperature by minimizing heat gain during warmer months and minimizing heat loss during colder ones. This increases indoor comfort and lowers energy consumption by using less energy on your heating and cooling systems.

The defense it provides against physical harm is yet another benefit. Insulation serves as a barrier against abrasion and mechanical impacts, which can come from natural elements or landscaping. This extra line of defense can help your foundation last longer, guaranteeing long-term durability and saving maintenance expenses.

In summary, adding external foundation insulation is a cost-effective upgrade that improves your home’s energy efficiency and structural robustness. The foundation of your building will last longer and be more sustainable if external insulation is used to mitigate moisture problems, enhance thermal performance, and fortify against physical wear and tear.

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