Treatment of metal roof leakage with aluminum foil self-adhesive waterproofing membrane

One: the current status of metal roof waterproofing

The most common materials for metal roofing in China are pressed sandwich composite insulation boards. Most of the large-span workshops, workshops and supermarkets are such roofs. However, from the waterproof design and waterproof measures, the profiled steel sheets are almost blank. According to the survey, the shape of the profiled steel roof after three years of construction is not more than 5%. The phenomenon of water seepage is very serious and the maintenance is very difficult. Roof panels such as aluminum-magnesium-manganese sheets, aluminum sheets, copper sheets or copper-plated sheets are relatively expensive and have relatively low engineering quantities. Most of its waterproof measures stay at the beginning, that is, they are connected with rubber parts or weather-resistant glue at the joint of the joints. There are very few people who have not been seeping water for five years, and the status quo is not optimistic.

The leakage of metal roofing is a difficult problem that is difficult to solve in the construction industry today. Has received attention and attention from people from all walks of life.

Two: the most fundamental cause of water seepage in metal roofing

There are many reasons for water seepage on metal roofs, such as insufficient gutter flow, unreasonable structural design, poor quality of plates, unreasonable installation, etc., which can cause metal roofing to seep. The water seepage caused by these human factors will gradually be gradually recognized and overcome by people. However, the most fundamental reason for water seepage is caused by the characteristics of the metal material. The use of metal materials is intended to use the advantages of metal materials, but it cannot avoid or overcome its shortcomings. This point begins with the physical properties of the metal material. First, the metal material has superior thermal conductivity, which is why people often say that the heat absorption is fast and the heat transfer is fast. This will cause the metal roof to heat up rapidly under the sun's illumination, and in the event of sudden extreme weather or night, the temperature will fall back quickly, causing a great temperature difference in the roof temperature. Second: the metal material has good ductility. This extension can be extended not only by the external force, but also automatically under the influence of temperature, and shrinks when it encounters low temperature. The combination of the two special properties of the metal material forms a thermal expansion and contraction of the metal.

Every day, the metal roof rises and falls with the sun, and it has to go through two sections of high temperature and low temperature. That is to say, the metal roof must have at least one extension and one contraction a day, and it will start again. Its power is huge. The roof of 30M span can produce 3cm-10cm shrinkage joints. Together with the effect of strong winds, the erosion and erosion of rainwater can easily cause deformation of roof panels, loose fasteners, widened seams, etc. phenomenon. Pressed steel roofing, under normal circumstances, local water seepage will occur after one winter and one summer. Even if the aluminum plate or the steel plate roof is treated with weather-resistant rubber or rubber parts for the joint of the plate, under such a large external force and frequent stretching, the waterproof effect is quickly lost, and water leakage and water leakage follow.

Treatment of metal roof leakage with aluminum foil self-adhesive waterproofing membrane

Three: How to solve the problem of water seepage in metal roofing?

The metal roof is at noon in summer, the metal surface temperature is as high as 70 °C and the night is only about 15 °C, the temperature difference is great. Ordinary polymer waterproofing materials or asphalt-based waterproofing materials, under such high temperature, coupled with the stretching of the roof panel caused by the temperature difference, quickly lose the waterproof effect, and the use will not exceed one summer. In the process of roof repair, many steel structure construction companies do not understand the truth. They use glass glue or ordinary waterproof materials for sealing treatment. As a result, it can be imagined that the waterproof function will not exceed one winter or one summer. Years of rain, annual maintenance.

Metal roofing not only has the great destructive power of thermal expansion and contraction, but also the high temperature in summer, the low temperature in winter, the vibration caused by strong wind, and so on. This puts higher and more demanding requirements on the selection of waterproof materials for metal roofing. Its waterproof material must meet the following characteristics before it can be used on metal roofing.

1) has a strong pulling force

2) has a strong elongation

3) High temperature resistance and low temperature resistance

4) has strong adhesion

5) Ability to reduce roof temperature

Four: metal aluminum foil self-adhesive waterproofing membrane

Metal aluminum foil self-adhesive waterproofing membrane is a high-end waterproof product developed for the special situation of high temperature and low temperature in winter in metal roof. This product can reduce the roof temperature to 5-15 °C, anti-aging, high temperature resistance and elongation. Excellent, high tensile strength, strong adhesive force, can be attached to irregular metal roof, can make metal surface layer completely isolated from air, waterproof, anti-corrosion, heat insulation, heat dissipation and so on. Cold construction, no damage to the metal finish and insulation. Convenient construction, remove the isolation film below, and paste the positive position.

1) Product structure and characteristics of metal aluminum foil self-adhesive waterproofing membrane:

a: Surface layer: Made of pure metal aluminum foil for surface layer, metal aluminum foil has the characteristics of reflection, heat dissipation, moisture resistance, heat insulation, anti-sun ultraviolet light, abrasion resistance and so on. The color temperature of the color plate roof can be reduced from about 70 °C to about 50 °C. Reducing the roof temperature reduces the ductility of the metal roof and conseques the destructive power caused by thermal expansion and contraction. Problems such as structural deformation, displacement, loose fasteners, aging of the topcoat, etc. are solved.

b: Self-adhesive layer: Adding aging-resistant butyl rubber, butyl rubber has a aging resistance of up to 40 years, strong adhesion, high elongation, and can be firmly and densely bonded to metal. The surface paint is no longer drummed, foamed, and peeled off, and the metal surface is no longer rusted. In the middle of the self-adhesive layer, a soft polyester cloth with ultra-thin and super-stretching force is added, which enhances the tensile strength of the coil material, and overcomes the problem that the coil material is not firmly adhered and warped when the irregular base surface is constructed.

c: Isolation film: isolation and protection of the self-adhesive layer.

Metal aluminum foil self-adhesive waterproofing membrane, ultra-thin structure, super tensile strength, super strong adhesion to the metal surface, wearing a protective outer coat for the metal roof. The superior anti-corrosion and waterproof effect prolongs the service life of metal roofing for 8-20 years. Cold construction, no need for primer. No need for gasoline, no longer worry about the fire caused by coil hot melt construction, environmental protection and energy saving.

2) Construction process of metal aluminum foil self-adhesive waterproofing membrane

1. Construction process

Base treatment ------- detail processing ------ paving coil ------ quality inspection and finished product protection

2. Grassroots treatment

If the roof panel is loose, it should be reinforced, and the edging should be leveled, and the rust should be rusted. The roof panel has a part that is in contact with the cement wall, the cement wall surface is painted with a base layer treatment agent, and the gutter is painted with a base layer treatment agent. Remove all debris from the surface of the old house, clean and free of dirt, oil, sand and other dirt on the surface.

Treatment of metal roof leakage with aluminum foil self-adhesive waterproofing membrane

3. Detail processing

The key water seepage parts such as rain inlets, air conditioning ducts, gutters, wall parts, and fan roots are covered with an additional layer with a width of 300mm. Or attach additional layers to the key water-permeable parts according to actual needs. The mouth of the mouth should be covered.

The main areas of major water seepage are:

1: At the nail hole, the nail hole is easy to rust, and the nail hole is treated first with a sealing paste.

2: The interface between the panel and the wall. The main treatment method is: cutting a 5cm×10cm square groove on the wall, pressing the bottom of the groove, and sticking the waterproof layer to the top, and filling it with crack-resistant mortar. Or directly fix the waterproof layer on the wall with a metal bead, and then seal the crimped part of the coil with a sealing material (as shown on the right).

3: The intersection of the roof column and the roof panel. It is one of the parts where steel structure roof is easy to seep. The main solution is to add a metal water barrier or metal waterproofing plate above the waterproof layer to relieve the momentum from the water above the steel column. The upper coil part should be constructed by the winding construction method, so that the coil material is not easy to fall off. The upper part of the water baffle is sealed with a sealing material.

(as shown on the right)

4. Spreading the coil

4.1. Eject the baseline on the base layer and position the coil. This saves the material and is neat and beautiful. The long direction of the web is perpendicular to the direction of the water flow, and the lap joint of the coil and the coil is laid in the direction of the flowing water.

4.2 Firstly, the parts with relatively concentrated drainage (such as drainage, gully, gutter, etc.) shall be laid in the order of low to high elevation. First lay the eaves and then spread them up. It’s simple and complicated,

First low and then high, first and then near scientific construction.

4.3 In the web where the paving plane is connected to the façade, the flat surface shall be laid first, the additional layer shall be pressed, and then the flat layer shall be pressed from the top to the bottom to press the flat coil. The top of the wall coil should be treated with a bead, and the upper part of the coil should be sealed. The material should be covered with sunscreen paint or sealant.

4.4 Large-surface paving coil: Open the coil, align the positive coil in the part to be constructed, roll the coil from both ends of the coil, cut the separator from the middle, and remove the separator. Spread the coil, then squeeze the coil hard, flatten it, and slowly move forward. Try to make the coil compact and flat. The nail should not be too hard. In case the nail is damaged against the material. After the first felt is applied, the 10 cm wide overlapping film reserved above is removed. The laying of the second felt web is started, and the second felt web is pasted on the overlap of the first felt. And so on.

4.5 Edge sealing treatment: After the construction is completed, all the side seams shall be edge-sealed, especially the water-side seams, and the edge-sealing materials must be painted.

4.6 After the completion of the construction, the entire waterproof layer should be strictly inspected, all the roof debris should be removed, and the problem should be solved immediately.

5. Construction precautions:

a: The overlapping width of the coil is not less than 50mm on the long side and not less than 100mm on the short side.

b: The pair of lap joints of the first coil and the pair of the second coil are not overlapped, and at least one meter is staggered. The overlap between the coil and the coil, between the coil and the reinforcing layer must be firm and there must be no warping.

c: Just after the construction of the waterproof layer, do not just uncover and paste elsewhere. If you open more than two times, it will not bond well, you must apply the base treatment agent to bond.

d: Windy, rainy, dusty, and foggy weather cannot be constructed.

e: It is best to leave the temperature below 15 degrees. In the winter construction, the base treatment agent should be applied.

f: If the original rainwater outlets and downpipes on the roof of the roof are damaged, they should be repaired in time.

g: Construction in the morning and evening, when the color steel tile surface has dew, stop construction.

h: Do not squeeze the coil too hard at the nail cap. There should be some space for the nail cap.

i: When the gap of the color steel tile exceeds 0.3MM, it should be reinforced, and the construction can be carried out after the treatment. The yin and yang angles, the pile façade and the plane yin angle, the façade inner corner and the outer corner must be added.

j: Storage of coil: The material should be stored in a cool and dry place, and should never be placed under the sun. During construction, how much is used, it will be transported to the roof a large amount, once used up.

k: Construction workers should wear soft rubber sole shoes, and it is strictly forbidden to wear hard bottom shoes with nails. During the construction process, non-process personnel are strictly prohibited from entering the site.

Five: the prospect of metal roofing waterproof materials

With the rapid development of light steel structure construction, the metal roof with the profiled steel plate as the mainstream has been popular in the north and south, and is increasing at an annual rate of 30%. The maintenance period is about five years, which means that the metal roof needs to be repaired, and the area is accumulated year by year. The waterproof area will account for about 30% of the waterproof market. The importance of waterproofing of new metal roofing has gradually been recognized and valued, and new metal roofing has also begun to consider waterproof design and waterproof construction. Metal roofing waterproof material demand, the market potential is huge!

Metal house facing waterproof materials mainly include: heat insulation, heat dissipation, high adhesion, anti-aging, beautiful appearance, can play the role of cooling, waterproof, anti-corrosion!