Expert Analysis: Application of Foam Glass on Building Walls

Editor:Zhejiang Zhenshen Insulation Technology Corp. Ltd. │ Release Time:2019-03-04 

The comprehensive performance of foam glass is very excellent. It has inorganic weathering material with strong weather resistance and durability. Its service life is synchronous with that of building. The coefficient of linear expansion is basically the same as that of concrete and other materials. The surface porosity is well bonded to cement mortar. The utility model has the advantages of convenient construction, high strength, low thermal conductivity, no water absorption and the like, strong resistance to ultraviolet rays, strong wind and rain, permanent heat insulation effect, and avoiding damage to the building structure caused by high and low temperature difference.

    First, the scope of use of the system

    Foam glass insulation system is suitable for exterior insulation of exterior walls of buildings, indoor partition walls, constant temperature and humidity workshops and internal and external insulation of machine rooms.

    Second, the physical indicators of the system core materials

    1. Physical properties of foam glass (see Table 1)

    2. Bonding mortar

    It is made of jj glue, ordinary cement, sand and expanded perlite to form bonded mortar. Its compressive strength and flexural strength are ≥4Mpa, and the bond strength is ≥0.9Mpa.

    3.Overlay mortar

    It is made of jj glue, ordinary cement, sand, anti-cracking fiber and expanded perlite. The compressive strength and flexural strength are ≥10Mpa, the flexural strength is ≥4Mpa, and the bond strength is ≥1.2Mpa.

    Third, the characteristics of foam glass exterior insulation system

    1. Safe and reliable

    The foam glass exterior insulation system is simple in construction and light in weight. The cement and cement mortar are used for bonding and covering. The weather resistance is good and the wall surface is firmly bonded, and the overall performance is good, which can effectively avoid the risk of the insulation layer falling and falling.

    2. Energy saving effect is permanent

    Foam glass is an inorganic material, which is closed, light and aging, and the heat preservation performance is not reduced by any external factors.

    3. Strong impermeability

    The foam glass itself has closed cells and does not absorb water, and the surface layer of the polymer cement mortar also has strong waterproof performance, so the system not only heats the insulation, but also solves the waterproof leakage of the wall surface.

    4. Good impact resistance

   The external wall thermal insulation foam glass has high strength (≥0.5MPa), and the overlying polymer cement mortar has greater impact strength.

    5. Simple construction without pollution

    The polymer cement mortar formulation is simple (or corresponding dry mortar). Traditionally hand-pressed and pasted foam glass. The materials used in the system are non-toxic and harmless, no white pollution, and are purely green products.

    Fourth, the construction points of foam glass exterior insulation system

    1. The order of operation of the wall

   When the exterior wall is covered with foam glass, the surface layer of the wall should be immersed with no water, and the surface of the foamed glass should be cleaned with compressed air or a brush to remove the surface ash, and scraped with a toothed trowel on the back and sides. About 2mm thick bonding mortar, while scraping 2mm thick bonding mortar on the wall surface, immediately stick the foam glass on the wall surface, squeeze it tightly with the surrounding paste, and then gently tap it with a rubber hammer. Make it bond firmly, and stick the block to the block. When the excess mortar is squeezed out, it should be scraped off immediately.

    2. Paving installation method

    When paving, it is generally laid from top to bottom and horizontally in the horizontal direction. (It can also be from bottom to top. When the last part is under construction, in order to avoid falling movement, support should be added to make it stick and not slippery). The seams should be horizontally aligned between each layer, and the vertical direction should be staggered. When it is not possible to paste the whole piece, it is necessary to measure the size in advance, and cut it in the desired size on the spot, and do not cut it at will.

    3. Provisions for installing staples on the outer wall

   For high-rise buildings with a height of more than 4m and a floor height of more than 20m, fixed nails should be added. The spacing between the nails should be about 1.2m. The fixing point should be at the corner of the foam glass block and the anchoring depth of the wall must be 30mm.

    4. Time requirements for overcoat construction

    When the outer wall foam glass cover layer is applied, it should be applied after the foam glass is pasted for 2 days before the cover layer can be applied. The foamed glass insulation layer should be inspected before the construction. The flatness should be more than 2mm, and the gap between the plates should not be smooth. It should be done when it is full. When facing the surface coating or pasting the tile, after the surface layer mortar is hardened, the decorative layer can be applied in 1-2 days.

    5. Grid cloth paving method

    Remove the surface of the foamed glass insulation layer and remove it with a small amount of water, then wipe the surface mortar 3mm. After smearing, the mesh cloth is laid, and the mesh cloth is pressed into the mortar with a trowel. The mesh cloths are overlapped by about 3 mm, and the mesh cloth should be smooth, not wrinkled, delaminated, and after the mortar is initially set. Then wipe the cover layer 2mm and smooth, compact and calender. If the wall design is not laid with mesh cloth, additional reinforced mesh cloth shall be added at the corner of the wall and the corner of the wall at the corner of the wall, about 100mm on each side.