Rauta experts with many years of experience in the selection, design, supply and installation of sandwich panels have briefly answered the main questions how to choose and use sandwich panels in the construction of energy-efficient buildings.
What are the types of sandwich panels?
By purpose, sandwich panels are divided into wall and roof. Wall panels are used for the construction of external walls, internal partitions, as well as suspended ceilings.
In shape, wall panels can be flat, radius and angular.
By type of fastening, wall sandwich panels are distinguished with visible and hidden fastening, roof panels are mainly used with visible fastening, but there are roof panels with hidden fastening using clips.
By the specific application, sandwich panels are standard, energy-efficient, for cold stores, for fire-resistant partition walls, acoustic and translucent.
How to choose the type of sandwich panel core?
Sandwich panels re available with five main types of insulation: mineral wool (MW), glass wool (GW), polyisocyanurate foam (PIR), polyurethane (PUR) and expanded polystyrene (EPS). The sandwich panel core is selected depending on the characteristics of operation and requirements for building structures:
What are the types of sandwich panel facing?
Sandwich panel facings are made of galvanized steel with coating, stainless steel and weather-resistant Cor-Ten steel.
What are the types of profiling of sandwich panel facing?
The most common profiling:
What are the facade claddings of sandwich panels?
To increase the architectural attractiveness of buildings made of sandwich panels, ventilated facades with steel cladding can be used, the substructure of which is attached directly to the panel facing. In such cases, it is recommended to use panels with increased load-bearing capacity and thicker facing. To minimize the impact of the cladding on the panel facing, it is important to use sandwich panels and ventilated facades made of high-quality steel and a polymer coating that meet the conditions of the increased category of corrosive aggressiveness of the environment.
How to choose a polymer coating for sandwich panel facing?
The coating for sandwich panel skin is selected depending on the operating conditions and the category of corrosive aggressiveness of the environment.
For the correct selection of the coating, it is important to know what physical and chemical influences the internal and external facing of the panels will be exposed to.
The most common coatings for sandwich panel facing:
To protect the outer surface of the panels from graffiti, there is a special anti-vandal coating that allows you to easily wash off graffiti made with markers or spray guns with paint.
Polymer coatings for steel facades and roofs
What thickness of sandwich panels should be chosen?
Standard thicknesses of sandwich panels with PIR, PUR and EPS core are usually vary from 40 to 200 mm, and with mineral wool – from 80 to 230 mm.
The key criteria for choosing the thickness are:
For cold rooms, there are additional criteria for selecting the thickness of sandwich panels.
What is the width of sandwich panels?
The most common widths of wall sandwich panels are 1,000 and 1,100 mm. Optionally, it can be 600, 900 and 1,200 mm. The standard width of roof sandwich panels is 1,000 mm, some manufacturers have up to 1,100 mm.
Advantages of sandwich panels of greater width:
Advantages of sandwich panels of smaller width:
What is the length of sandwich panels?
The length of sandwich panels is usually limited by the dimensions of vehicles and is up to 13.2 m. If necessary, it is possible to manufacture sandwich panels with an oversized length of up to 18.5 m, but their transportation and installation will be complicated.
For horizontal installation, sandwich panels with a length of 6 m are usually used, which corresponds to the typical step of columns in commercial buildings.
How to choose sandwich panels for cold stores?
The thickness of sandwich panels for refrigerators is selected considering the required temperature inside the premises and the level of the temperature difference, the average annual ambient temperature or the temperature of the adjacent room.
For chambers with a regulated gas environment, it is critically important to have minimal air permeability of structures, the absence of cold bridges and freezing of some areas, therefore, in addition to special cold-stores sandwich panels, in the construction of refrigerated and freezer chambers, technology is used that ensures the tightness of the locks and joints of sandwich panels.
For safe storage of food should be used sandwich panels with an inner facing with a special Food Safe (PVC) coating or made of stainless steel.
What are the energy efficiency indicators of sandwich panels?
The main thermal properties that determine the energy efficiency of sandwich panels: heat transfer coefficient U, the resulting heat transfer resistance R and the effective thermal conductivity of the core λ.
The most important parameter of the energy efficiency of sandwich panels is the heat transfer resistance R, which takes into account heat losses in the joint part of the structure. Minimum thermal resistance indicators for high quality sandwich panels:
Panel thickness, mm | Thermal resistance R0, m2*K/W | |
| Mineral wool | PUR/PIR | |
| 40 | – | 2,0 |
| 60 | – | 2,9 |
| 80 | 2,1 | 3,8 |
| 100 | 2,6 | 4,7 |
| 110 | 2,8 | 5,2 |
| 120 | 3,1 | 5,7 |
| 140 | 3,6 | 6,6 |
| 150 | 3,8 | 7,0 |
| 160 | 4,1 | 7,5 |
| 170 | 4,3 | 7,9 |
| 180 | 4,6 | 8,4 |
| 200 | 5,1 | 9,3 |
| 210 | 5,3 | – |
| 230 | 5,8 | – |
How to make a sandwich panel structure as more energy-efficient as possible?
Key factors that affect the energy efficiency of a sandwich panel structure:
What is the fire resistance of sandwich panels?
High-quality sandwich panels with PIR core provide fire resistance up to EI60.
The maximum fire resistance of sandwich panels with mineral wool is up to EI240.
The fire barrier system of Ruukki sandwich panels provides fire resistance under mechanical impact up to EI-M120.
How to make fireproof partition walls from sandwich panels?
The basis of fireproof partitions are special mineral wool sandwich panels with high fire resistance. Additional fire protection is provided by sealing all joints with mineral wool, using gaskets with fire-resistant sealants, as well as a system of reinforced fastening of structural elements to each other.
What are the acoustic properties of sandwich panels?
Sandwich panels have two main acoustic characteristics: sound insulation (reducing the noise level after passing through the wall) and sound absorption (creating acoustic comfort inside the room).
Sound insulation of sandwich panels Rw is up to 24 dB for high-quality PIR panels and up to 32 dB for mineral wool panels.
Standard sandwich panels have a sound absorption coefficient αw=0.1; This means that 90% of the sound is reflected and 10% is absorbed. Ruukki offers special acoustic sandwich panels for rooms with high noise levels (sports halls, production facilities, etc.) The inner surface of such panels is perforated to allow sound to pass into the structure, where it is effectively absorbed by the mineral wool core. The sound absorption coefficient of such sandwich panels is αw=0.85 (class B), which is sufficient to ensure acoustic comfort.
What is better: sandwich panels or sandwich panels/internal wall cassettes (IWC)?
To create an architecturally attractive and energy-efficient building, it is better to use sandwich panels. The advantage of IWC is its lower price, but significant disadvantages, such as high heat loss, difficult installation and low durability clearly indicate the feasibility of using sandwich panels.
Comparison of IWC and sandwich panels
Can sandwich panels be used in corrosive aggressive environments?
Sandwich panels can be used in environments with increased corrosive aggressiveness provided that the material and thickness of the steel facings are correctly selected, as well as the type of protective coating that will meet the operating conditions and ensure the durability of the structure.
How to choose envelope structures for aggressive environments
Can sandwich panels be used in areas with increased seismic activity?
Sandwich panels can be used in seismically hazardous areas during earthquakes magnitude intensity up to 7 points, provided that the correct selection and calculation of the load-bearing capacity are made. When using sandwich panels in construction in areas of increased seismic activity, the supplier must additionally provide a conclusion on seismic resistance.
What is the environmental friendliness of sandwich panels?
Sandwich panels are ecological products that do not harm the environment. The technology of sandwich panel production differs among different companies, so for the construction of buildings that will be certified according to environmental standards LEED or BREEAM, etc., you should check:
Are sandwich panels suitable for reconstruction?
Yes, sandwich panels are one of the best solutions for the reconstruction of buildings, as they are easy to install, have a relatively low weight with a large area, which allows you to quickly install walls, and also increase the energy efficiency of the building.
Is it possible to build a cottage made of sandwich panels?
Yes, frame cottages from sandwich panels are quite widespread in Europe and the USA due to their quick construction and highest energy efficiency. Rauta has developed frameless cottages made of sandwich panels, which have a number of advantages over classic construction technologies.
Can sandwich panels be used for the walls of multi-storey buildings?
Yes, wall structures of multi-storey buildings made of sandwich panels are a new technology that allows you to increase the usable area of the premises by up to 5% compared to masonry from piece materials.
More details on the use of sandwich panels for multi-storey buildings
Can sandwich panels be used for the construction of clean rooms?
Yes, the best solution for walls and ceilings of clean rooms is sandwich panels with PIR core and steel facing covered with FoodSafe film laminate, which has high wear resistance when exposed to substances of organic origin, is easy to clean and does not absorb water.
More about clean room construction
Can sandwich panels be used as a blast wall?
Yes, blast wall structures made of sandwich panels are an effective solution for walls of explosive buildings in which the design does not provide for the presence of windows. Such blast walls are cheaper than translucent structures, and also ensure the architectural integrity of the facade and high energy efficiency of the building.
More about blast walls made of sandwich panels
What are the colors of sandwich panels?
Sandwich panels are manufactured in a wide range of colors according to the RAL and NCS catalogs. Most manufacturers have a standard color palette, which includes up to 10 colors, and an extended one, which adds up to 20 more colors. Some manufacturers have proprietary color palettes (for example, RR at Ruukki), and also offer panels with designer textures, for example, wood.
What are examples of beautiful buildings made of sandwich panels?
Commercial buildings made of sandwich panels, combined with impressive architecture and the additional use of ventilated facades, can have a very harmonious and attractive appearance, which is confirmed by examples of hundreds of buildings implemented around the world.
The most beautiful buildings made of sandwich panels
What producers of sandwich panels are operating in Ukraine?
There are several sandwich panel production plants in Ukraine: USP, Pantec, INTECO, TPK, Termo-BUD, Arsenal, NTK, BF Zavod, as well as more than twenty sandwich panel importers, among which the most famous are Ruukki, Kingspan, Balex, Paneltech and Gor-Stal.
How to choose a sandwich panel producer?
Sandwich panels are selected according to the following main criteria:
In addition to the characteristics of sandwich panels, it is also important to pay attention to the supplier’s ability to provide proper technical support for the project, which should include: providing detailed drawings and BIM models, developing panel layouts and specifications for additional elements, and technical supervision during the installation process.
What is the price per m2 of sandwich panels?
The price of sandwich panels depends on the following criteria:
The price of Ukrainian-made PIR panels starts from 15.5 €/m2 (with a thickness of 40 mm), for mineral wool – from 17.5 €/m2 (80 mm). Imported sandwich panels price starts from 20 €/m2 with polyisocyanurate filler and from 31.5 €/m2 with mineral wool.
More details about the price of sandwich panels
How to calculate sandwich panels by loads?
The selection of sandwich panels is carried out according to load-bearing capacity tables or calculation programs such as TrayPan, so before buying sandwich panels, you should make sure that the supplier has it.
What structural scheme for fastening sandwich panels is the most suitable?
It is better to use a single-span scheme for fastening sandwich panels to the load-bearing frame. With such a fastening scheme, minimal internal stresses from temperature and other loads arise inside the sandwich panels, which minimizes the risks of bending or destruction of the panels.
How to select fasteners for sandwich panels?
Self-drilling screws, nails, anchor bolts, etc. can be used to fasten sandwich panels.
The material and type of fasteners are selected depending on the following factors:
Usually, the designer, in cooperation with the panel supplier, is responsible for calculating and selecting fasteners.
What load-baring frame is suitable for sandwich panels?
All types of frames are suitable for the arrangement of envelope structures made of sandwich panels: steel, reinforced concrete, wooden or mixed.
The frame must have sufficient rigidity and load-bearing capacity to withstand all design loads, including from the panels, as well as precise geometry for high-quality installation.
How does color affect the performance characteristics of sandwich panels?
When choosing the color of sandwich panels, it is worth considering the ability of steel of different colors to heat up to different temperatures and extend with different coefficients of thermal expansion, which can affect product damage, aesthetic and thermal parameters of the building.
Dark-colored exterior cladding is subject to greater thermal deformations from heating under the influence of solar radiation, which leads to:
Recommendations for the use of dark-colored sandwich panels
Where to download 3d models of sandwich panels?
Leading sandwich panel producers, such as Ruukki, offer publicly available BIM models of their products for major computer-aided design programs such as: AutoCAD, Revit, Archicad and Tekla Structures.
You can download sandwich panel libraries on the relevant product pages.
Where to get detailed drawings of sandwich panel assemblies?
Sandwich panel assemblies (joint, external corner, parapet, eave, base, window/door/gate adjacency, etc.) are provided by the manufacturer in the album of technical solutions in PDF and DWG formats.
Suppliers can also develop individual design solutions if they are not included in the standard list of assemblies.
Sandwich panel assemblies can be downloaded on the relevant product pages.
What standards regulate the use of sandwich panels?
DSTU EN 14509 “Self-supporting thermal insulation panels with double-sided metal cladding. Factory-made products” is the main standard that regulates the quality of sandwich panels in Ukraine and EU countries.
| Document | Regulations |
| DSTU EN 10143 | Sheet thickness |
| DSTU EN 10346 | Steel grade of external facing |
| DSTU EN 10169 | Coating of external facing |
| DBN В.2.6-31 | Thermal insulation capacity |
| DSTU EN 12865 | Water permeability class |
| DSTU EN 12114 | Air permeability |
| DSTU EN 13501-1 | Reaction to fire class |
| DSTU EN 13501-2 | Fire resistance |
| DSTU EN ISO 717-1 | Airborne noise insulation |
| DSTU EN ISO 11654 | Sound absorption |
| DBN В.2.6-31 | Effective service life of the core |
| DSTU Б В.2.7-169, DSTU Б В.2.6-38 | Structural integrity warranty period |
What certificates are required for sandwich panels?
Certification of sandwich panels in Ukraine is not mandatory, however, the Law of Ukraine “On the Placing of Construction Products on the Market” (EU Regulation 305) obliges suppliers and manufacturers of products to draw up and register with the Unified State Slectronic System in Construction declarations of conformity of sandwich panel characteristics.
Sandwich panel producers can voluntarily undergo certification according to the FM standard, receive a conclusion on seismic resistance and a sanitary and epidemiological conclusion (required for pharmaceutical and food industry facilities, etc.), as well as draw up environmental product declarations EPD.
Ruukki sandwich panels have been certified according to the Scandinavian burglary resistance standard SSF 1047-2, which provides for the classification of wall structures according to protection against mechanical burglary. Depending on the thickness of the product, Ruukki panels have certificates for security classes 2 and 3.
Which direction of installation of sandwich panels is better: vertical or horizontal?
The direction of installation depends on architectural preferences. The advantages of horizontal installation include lower material consumption of the frame, since this scheme does not require the arrangement of additional purlins, and better tightness of the wall. The advantage of vertical installation is the visual integrity of the facade due to the absence of joints.
How to install sandwich panels?
Installation of sandwich panels is one of the most important components of obtaining an architecturally attractive, energy-efficient and durable structure. Therefore, the installation of panels should be done by professional contractors who are well versed in technology, know the features of the arrangement of joints and follow all the manufacturer’s recommendations for the installation of sandwich panels and accessories.
Detailed instructions for installing sandwich panels
What is the price for sandwich panels installation?
The price of installing sandwich panels depends on the following factors:
On average in Ukraine, the cost of installing sandwich panels, taking into account the cost of machines and mechanisms, is from 15.5 €/m2 to 21.5 €/m2 with VAT.
Is it possible to install sandwich panels in winter?
Installation of sandwich panels in winter is allowed under certain conditions:
What is the service life of sandwich panels?
The service life of buildings, including envelope structures, is determined by DBN V.1.2-14 and ranges from 15 to 100 years depending on the type of building.
The durability of sandwich panels of different manufacturers and types can vary significantly and depends on the quality of the products, as well as the correctly chosen type of facing and core. Depending on the producer, the effective service life of sandwich panels varies from 10 to 100 years. The maximum effective service life of Ruukki sandwich panels, confirmed by test reports, is up to 100 years.
What is the warranty period on sandwich panels?
There are several types of warranties for different characteristics of sandwich panels:
More details about the warranty on sandwich panels
