How to effectively heat the roof of cold storage

How to effectively heat the roof of cold storage

In order to reduce the influence of outdoor air temperature on the interior, the cold storage roof must be insulated. Currently, there are usually the following two approaches.

　　1. Insulation material ceiling is set on the bottom of the panel

　　 This kind of roof insulation method does not install attic floor but makes the insulation layer and roof together. Usually, the thermal insulation layer composed of cork board, polystyrene foam plastic board and other block thermal insulation materials is made under the roof structure layer. Under the thermal insulation layer, a pour-out 18mm thick tongue and groove board is used as a protective layer and then brushed Two layers of tung oil, this kind of roof insulation layer has the advantages that it is not affected by the weather during construction and will not form a cold bridge at the junction of the roof and the wall, but the construction is more troublesome. It is labor intensive and can not use loose insulation materials. This approach is generally applicable to small cold storage and reconstruction of cold storage.

　　 Compared with the roof insulation method of no attic floor, the advantage of installing an insulating material roof under the roof panel is that one time investment is saved. The disadvantage is that the roof leakage is not easy to find and the pool is difficult to repair, and the solar radiation heat has a greater impact on the cold storage warehouse. Therefore, it is less used in the South.

　　 2. Attic floor on top of library

　　 There is a mezzanine floor on the roof of the cold storage, and the roof insulation layer is laid on the mezzanine floor. This approach, although the addition of a structural layer, a corresponding increase in civil engineering investment, but it has more prominent advantages, so cold storage in various places widely use this form. Its main advantages are:

　　 (1) There is a large space in the shelf, which is convenient for operation to lay, replace or refurbish cheap loose insulation materials. Meehan generally uses rice husks

　　 (2) It is harder to check the leakage of the roof and various structural defects.

　　 (3) Harder than checking, filling or renovating the insulation material layer of the external wall part.

　　 (4) The horizontal cracks in the external wall caused by the roof expansion and contraction are moved up to the attic floor to avoid adverse effects in the cold storage.

　　 (5) During the construction process, it is not affected by the weather and can cut off the water earlier than the roof form with the actual insulation layer. "It is beneficial to the construction of the insulation and vapor barrier of the entire warehouse.

　　 There are two commonly used structural forms of cold storage mezzanine floors, which are hanging the ceiling on the lower string of the long-span roof truss. This form is often used in single-story sloping roof cold storage. This form must deal with the problem of "cold bridge" of the hanging ribs. Hardwood insulating blocks are usually placed under the hanging ribs. The other form is reinforced concrete beam-slab structure or beamless structure, which has the advantages of good rigidity and integrity, and good construction and operation conditions of the tidy insulation layer in the attic. However, there is also the problem of column "cold bridge" and the cost is also high. Higher. This form is often used in multi-layer cold storage or single-layer flat roof cold storage.

　　 According to the ventilation of the attic floor, the form of the attic can be roughly divided into three types: ventilated, enclosed and mixed. These three types of lofts have different vapor barriers, such as "no vapor barrier", "double-sided vapor barrier", "cold side vapor barrier" and "hot side vapor barrier". Theoretical research and practice have proved the use of heat The method of surface steam insulation meets the requirements of building thermal engineering and has a better effect. The cold side vapor barrier is unreasonable and is generally not used now.