1. What is a SIP Panel?
SIP (structural insulated panel) is the term which has been known in Poland for years; it was developed in the USA already in 1935, At that time, Forest Product Laboratory acting upon the aegis of the American Department of Agriculture constructed the house in SIP technology in the state of Wisconsin. It was assumed that the planking from plywood and wooden boards would receive a part of the loads. The structure of this house was a frame one and it was enclosed by the panel connections. Such a solution was later used by Frank Lloyd Wright, the renowned American architect under the realization of his idea of creation of new American lifestyle, the so-called “Usonian style”. On the other hand, his student, Alden B. Dow, the son of the founder of the Dow Chemical Company, introduced a foam core into the panels; such SIP structure is used until today. On the other hand, the development of computer technology and electronics enabled easy production of already cut panels and the production of panels for a specific house design. This caused a significant progress in the application of panels in construction industry, which later led to the creation of appropriate standards for this type of structures, prepared, among others, by the NAHB Research Centre (the research centre of the American association of home building industry). Also SIPA was founded – the association of panel producers, promoting this technology in the USA and all over the world. Due to its strength characteristics, these houses became popular in seismic areas in the USA and in Japan.
SIP is a composite sandwich board consisting of a core (Styrofoam, polyurethane) and facing made from OSB, cement, magnesium or aluminium board, and even carton and gypsum board. In the EU countries, such board is subject to standards that are described in the guidelines to European Technical Approvals ETAG no. 016. Composite sandwich boards are included in European standards as self-bearing boards, i.e. that do not receive any vertical loads. In classical solutions, SIPs are combined using the so-called spline. On the other hand, in the case of connections in the areas with the planned structural elements, such as pillars and bolts, wooden beams of appropriate thickness are placed, from which a continuous framework structure of the building can easily be constructed. There are also solutions in which reinforced concrete cast in the channel area between the panels is used instead of timber.
2. What is MgO Green?
The system is based on the standard SIP composite panels technology, which has been improved by means of replacement of OSB facing with a cement and magnesium board reinforced with glass fibre mesh under the commercial name MgO Green. Thus the structural and insulation composite panel (CSIP) is formed.
3. How is SIP MgO Green Panel built?
MgO Green panel consists of three parts – two external layers- the facing and the Styrofoam layer. The insulation and structural core is made from EPS-100 Styrofoam. The core is connected with the facing using pressure in the press by means of a single component adhesive based on polyurethane. The facing can be performed in one of the three configurations specified below:
- as two MgO Green-LS-TECH magnesium boards
- as two OSBs
- as a combination of MgOreen-LS-TECH board and OSB
4. Why should we use magnesium boards?
Magnesium oxide properties were appreciated by the Chinese already during the construction of the Great Wall of China, and the world, especially the Far and Middle East started to use magnesium boards after the attacks from September 2001, primarily in multi-storey buildings with steel structure for the protection of structural elements against fire. Magnesium boards were also used for cladding walls in all Olympic facilities in Beijing.
MgO magnesium boards are mainly produced in China in a few hundred factories for local needs; there are over a dozen producers at the global level that deliver the product with high fire and water resistant properties, as well as good strength properties, similar to fibre and cement boards. China is not interested in exporting magnesium oxide and therefore it became the basic producer of magnesium boards. There are also other methods of obtaining magnesium oxide than from periclase occurring in China; at present we are conducting research aimed at the implementation of these methods.
5. What is the MgO magnesium board made from?
A classical magnesium board is a sandwich board consisting of the core from powdered perlite, surrounded on both sides with a mesh from glass fibre and magnesium layer MgO or magnesium-cement layer, which is often reinforced (in a dispersed manner) with cellulose fibre with the addition of other derivatives of magnesium compounds, such as magnesium chloride – MgCl2.
The basic composition of magnesium boards is as follows: MgO – 50%, MgCl2 – 25%, perlite 8.5%, fibrous cement 15%, glass fibre 0.5% as well as other components (e.g. cellulose) 1%.
Perlite (volcanic glass) is little known material in Poland, used in construction, which occurs naturally as a volcanic rock. It is characterised by a very low weight and bubble-like structure, thanks to which it can be used as an insulation material. The concept of dispersed reinforcement and glass fibre reinforcement is also little known in Poland, and therefore it can be concluded that magnesium board in the technological perspective is quite a sophisticated product, which is nevertheless accessible in financial terms and which significantly improves the standard of structural facilities.