An anti-permeation and anti-cracking structure for a joint position of an external wall of a sandwich insulation board and a method thereof
By using measures such as beveled tongue and groove joints combined with ventilation and drainage facilities and water-swellable waterstop strips at the joints of the exterior walls of prefabricated residential buildings, the problems of leakage and cracking of the exterior walls were solved, achieving efficient waterproofing and structural stability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHINA MCC17 GRP CO LTD
- Filing Date
- 2026-05-09
- Publication Date
- 2026-07-10
AI Technical Summary
Prefabricated residential buildings are prone to leakage and cracking at the joints of their exterior walls. Existing technologies are unable to adapt to building deformation and complex environmental stresses, leading to structural safety hazards and increased maintenance costs.
The structure employs a combination of sloping tongue and groove joints with a lower outer edge and a higher inner edge, along with ventilation and drainage facilities. It also uses water-swellable waterstop strips and alkali-resistant mesh fabric, combined with silicone weather-resistant sealant, to form a multi-layered waterproofing mechanism to accommodate structural deformation.
It effectively prevents rainwater from seeping in and drains it in a timely manner, reduces cracking and leakage at the joints, lowers rework and repair costs, and improves the long-term stability and safety of the exterior wall.
Smart Images
Figure CN122358784A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of exterior wall joint construction technology, and more specifically, to a waterproof and crack-resistant structure and method for the joint position of sandwich insulation board exterior walls. Background Technology
[0002] Prefabricated housing has gained widespread application in the construction industry in recent years due to its significant advantages in high efficiency, energy saving, and environmental sustainability. However, leakage and cracking at the joints of exterior walls have become a key bottleneck restricting its further development. In traditional construction methods, joint treatment often relies on a single sealing material, such as ordinary weather-resistant sealant or simple filling insulation material. This approach is difficult to adapt to the effects of building deformation and complex environmental stresses. For example, temperature changes cause materials to expand and contract, making the joints prone to micro-cracks. Moisture can then penetrate through capillary action, leading to leakage. At the same time, structural settlement or wind loads can cause joint deformation, leading to the peeling and failure of the sealing layer, further exacerbating the risk of cracking. In existing technologies, although some methods alleviate the problem by adding drainage cavities or using elastic sealing strips, drainage cavities are prone to blockage, and elastic sealing strips will age and lose elasticity after long-term use, resulting in a significant decrease in waterproofing effect. In addition, according to fire protection codes, joints must be filled with Class A materials, but conventional insulation materials cannot simultaneously provide both fire resistance and waterproofing performance, leading to condensation accumulation and potential leakage hazards. Leakage not only affects the durability of buildings but also increases later maintenance costs and can even lead to structural safety hazards such as concrete corrosion and insulation layer failure. Therefore, there is an urgent need for an innovative construction method that significantly improves the seepage resistance and crack prevention capabilities of joints by constructing multiple waterproofing mechanisms and dynamically adapting to structural deformation. This patent aims to address these pain points, providing an efficient and reliable solution to ensure the long-term stability and safety of prefabricated residential exterior walls. Summary of the Invention
[0003] 1. The technical problem that the invention aims to solve
[0004] To address the shortcomings and deficiencies of existing technologies, this invention provides a seepage-proof and crack-resistant structure and method for the joints of sandwich insulation panels in exterior walls. It employs a sloping tongue-and-groove joint with a lower outer edge and a higher inner edge, combined with ventilation and drainage facilities to effectively prevent rainwater from seeping into the interior and to promptly drain water from the cavities. The sealing layer uses water-swellable waterstop strips to further enhance the waterproofing effect. Alkali-resistant mesh fabric is pasted into the grooved areas to reduce cracking at the joints, effectively reducing the economic losses caused by leakage and cracking at the joints of prefabricated residential exterior walls, which would otherwise require rework and repair.
[0005] 2. Technical Solution
[0006] To achieve the above objectives, the technical solution provided by the present invention is as follows:
[0007] The present invention provides a seepage-proof and crack-proof structure for the joint of a sandwich insulation board exterior wall, comprising a composite slab and a prefabricated exterior wall. The prefabricated exterior wall is provided on the outer side of the composite slab. The prefabricated exterior wall includes an outer leaf slab, a insulation layer, and an inner leaf slab, which are distributed sequentially from the outside to the inside.
[0008] The surface of the prefabricated exterior wall slab has a beveled tongue and groove, and the outer surface of the prefabricated exterior wall slab has a groove, and the surface of the groove is covered with alkali-resistant mesh cloth.
[0009] Water-swellable waterstop strips are embedded on the outer side and both ends of the prefabricated exterior wall inner leaf slab;
[0010] Metal ventilation and drainage devices and PE rods are placed at the joints of the two sets of prefabricated exterior walls; the metal ventilation and drainage devices include metal conduits and gravel and sand wrapping bags.
[0011] The joint between the metal conduit and the prefabricated exterior wall is sealed with silicone weather-resistant sealant.
[0012] Furthermore, the metal ventilation and drainage device and PE rod are constructed after the main structure has settled and stabilized.
[0013] Furthermore, the groove has a depth of 8-10mm, and the outer surface of the groove is covered with alkali-resistant mesh cloth and coated with waterproof and crack-resistant mortar.
[0014] Furthermore, the application of the aforementioned silicone weather-resistant sealant is carried out after the application of the alkali-resistant mesh and the waterproof and crack-resistant mortar.
[0015] Furthermore, after the alkali-resistant mesh fabric is installed, a caulking seam is cut out for caulking, ensuring that the caulking area is exposed outdoors, and the silicone weather-resistant sealant is applied to the visible seam.
[0016] Furthermore, the oblique tongue and groove joint adopts an inner high and outer low design.
[0017] Furthermore, the water-swellable sealing strip expands and deforms 2-3 times upon contact with water, filling all irregular surfaces, cavities, and gaps in the joint, while generating enormous contact pressure to completely prevent leakage.
[0018] A construction method for a waterproof and crack-resistant structure at the joints of a sandwich insulation board exterior wall, comprising the following steps:
[0019] Step 1: During the detailed design and production stage, prefabricated exterior wall joints and grooves are installed at the junctions of the prefabricated exterior walls;
[0020] Step 2: Before hoisting the prefabricated exterior wall components, seal the outer side and both ends of the exterior wall with water-swellable sealing strips;
[0021] Step 3: After the prefabricated exterior wall components are hoisted and the main structure has settled and stabilized, clean up the rubble and debris in the joint cavities;
[0022] Step 4: Place a metal ventilation and drainage device and a PE rod at the seam.
[0023] Step 5: Adhere alkali-resistant mesh fabric to the groove and apply waterproof and crack-resistant mortar, with the same thickness as the groove;
[0024] Step 6: Locate and mark the seam positions, use a cutting device to cut the seam to the designed width, clean the area again, attach sponge strips along both ends of the seam and apply adhesive.
[0025] 3. Beneficial effects
[0026] Compared with the prior art, the technical solution provided by this invention has the following advantages:
[0027] This invention effectively prevents rainwater from seeping into the interior by using a combination of a sloping tongue and groove joint with a lower outer surface and a higher inner surface, along with ventilation and drainage facilities. It also ensures timely drainage of water from the cavity. The sealing of the cavity uses a water-swellable water-stop strip to further enhance the waterproof effect. The grooved area is pasted with alkali-resistant mesh cloth to reduce cracking at the joints. This invention effectively reduces the economic losses caused by leakage and cracking at the joints of the exterior walls of prefabricated houses, which would otherwise require rework and repair. Attached Figure Description
[0028] Figure 1 This is an overall diagram of the present invention;
[0029] Figure 2 This is a partial enlarged view of the present invention;
[0030] Figure 3 This is a structural diagram of the metal ventilation and drainage device of the present invention.
[0031] In the diagram: 1. Composite slab; 2. Precast exterior wall slab; 3. Precast exterior wall insulation layer; 4. Precast interior exterior wall slab; 5. PE rod; 6. Silicone weather-resistant sealant; 7. Water-swellable waterstop strip; 8. Beveled tongue and groove joint; 9. Metal ventilation and drainage device; 901. Metal conduit; 902. Crushed gravel and sand wrapping bag; 10. Alkali-resistant mesh fabric; 11. Groove. Detailed Implementation
[0032] The present invention will be further described below with reference to the accompanying drawings and embodiments:
[0033] Example 1
[0034] from Figure 1-3As can be seen, the anti-seepage and anti-cracking structure at the joint of the sandwich insulation board exterior wall in this embodiment includes a composite slab 1 and a prefabricated exterior wall. The prefabricated exterior wall is provided on the outside of the composite slab 1. The prefabricated exterior wall includes a prefabricated exterior wall outer leaf slab 2, a prefabricated exterior wall insulation layer 3 and a prefabricated exterior wall inner leaf slab 4. The prefabricated exterior wall outer leaf slab 2, the prefabricated exterior wall insulation layer 3 and the prefabricated exterior wall inner leaf slab 4 are distributed from the outside to the inside.
[0035] The surface of the prefabricated exterior wall slab 2 is reserved with a beveled tongue and groove 8, which adopts a design that is higher on the inside and lower on the outside.
[0036] Rainwater has difficulty penetrating into the interior due to gravity, and the steel mesh in the two parts of the precast exterior wall slab is denser to reduce the occurrence of cracking;
[0037] The outer surface of the precast exterior wall slab 2 has a groove 11, and the surface of the groove 11 is covered with an alkali-resistant mesh cloth 10.
[0038] Water-swellable waterstop strips 7 are embedded on the outer side and both ends of the precast exterior wall inner leaf slab 4; the water-swellable waterstop strips 7 are embedded before the vertical components are hoisted.
[0039] Metal ventilation and drainage devices 9 and PE rods 5 are placed at the joints of the two sets of prefabricated exterior walls; the metal ventilation and drainage device 9 includes a metal conduit 901 and a gravel and sand wrapping bag 902; one end of the metal conduit 901 is covered with a gravel and sand wrapping bag 902; to prevent mud and sand from clogging the metal conduit 901 and to ensure smooth drainage.
[0040] PE rod 5 prevents excessive penetration of silicone weather-resistant sealant 6 behind the joint, ensuring that silicone weather-resistant sealant 6 forms a reasonable bonding cross-section and avoiding stress concentration cracking caused by three-sided bonding.
[0041] PE rod 5 has a certain degree of compressibility, which can provide elastic support, adapt to minor deformations of the joints, and improve the durability of the waterproof layer.
[0042] The joint between the metal conduit 901 and the precast exterior wall is sealed with silicone weather-resistant sealant 6.
[0043] The metal ventilation and drainage device 9 and PE rod 5 were installed after the main structure had settled and stabilized.
[0044] The groove 11 has a depth of 8-10mm. The outer surface of the groove 11 is covered with alkali-resistant mesh cloth 10 and coated with waterproof and crack-resistant mortar to reduce the occurrence of cracking at the joint.
[0045] The application of silicone weather-resistant sealant 6 is carried out after the application of alkali-resistant mesh fabric 10 and waterproof and crack-resistant mortar.
[0046] After the alkali-resistant mesh fabric 10 is installed, cut out the caulking seams and apply caulking sealant, ensuring that the caulking area is exposed outdoors. The silicone weather-resistant sealant 6 is for visible seams, which is convenient for future maintenance.
[0047] Water-swellable sealing strip 7 expands and deforms 2-3 times its original size when exposed to water, filling all irregular surfaces, cavities and gaps in the joint, while generating huge contact pressure to completely prevent leakage; its water-stopping and waterproofing effects are more reliable than ordinary rubber, further reducing the risk of leakage.
[0048] Example 2
[0049] from Figure 1-3 As can be seen, the construction method of the anti-seepage and anti-cracking structure at the joint of the sandwich insulation board exterior wall in this embodiment is characterized by the following steps:
[0050] Step 1: During the detailed design and production stage, prefabricated exterior wall joints with tongue and groove 8 and groove 11 are set at the junction of the prefabricated exterior walls;
[0051] Step 2: Before hoisting the prefabricated components of the exterior wall, seal the outer side and both ends of the exterior wall with water-swellable sealing strips 7;
[0052] Step 3: After the prefabricated exterior wall components are hoisted and the main structure has settled and stabilized, clean up the rubble and debris in the joint cavities;
[0053] Step 4: Place a metal ventilation and drainage device (9 pieces) and a PE rod (5 pieces) at the seam.
[0054] Step 5: Adhere alkali-resistant mesh cloth 10 to the groove 11 and apply waterproof and crack-resistant mortar, with the same thickness as the groove 11;
[0055] Step 6: Locate and mark the seam positions, use a cutting device to cut the seam to the designed width, clean the area again, attach sponge strips along both ends of the seam and apply adhesive.
[0056] This invention patent relates to a construction method for preventing seepage and cracking at the joints of prefabricated sandwich insulation panels in exterior walls, belonging to the field of building assembly technology. During the installation of vertical components in prefabricated housing, leakage and cracking at the joints of exterior walls have become a key challenge restricting its development. Traditional construction methods often rely on single sealing materials, such as ordinary weather-resistant adhesive or simple filling with insulation materials, which are difficult to adapt to building deformation and complex environmental stresses. This leads to easy cracking and water seepage at the joints later on. This invention provides a simple, safe, and reliable construction method. The combination of a sloping tongue-and-groove joint (lower on the outside, higher on the inside) and ventilation and drainage facilities effectively prevents rainwater from seeping into the interior and promptly drains water from the cavities. The sealing layer uses water-swellable waterstop strips to further enhance the waterproofing effect, and alkali-resistant mesh fabric is pasted on the grooved areas to reduce cracking at the joints. This effectively reduces the economic losses caused by rework and repairs due to leakage and cracking at the joints of prefabricated housing exterior walls.
[0057] The present invention and its embodiments have been described above illustratively. This description is not restrictive, and the figures shown are only one embodiment of the present invention; the actual structure is not limited thereto. Therefore, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the spirit of the present invention, such designs should fall within the protection scope of the present invention.
Claims
1. A waterproof and crack-resistant structure for the joints of a sandwich-insulated exterior wall, comprising a composite slab (1) and a prefabricated exterior wall, characterized in that: The composite slab (1) is provided with a prefabricated exterior wall on its outer side. The prefabricated exterior wall includes a prefabricated exterior wall outer leaf slab (2), a prefabricated exterior wall insulation layer (3), and a prefabricated exterior wall inner leaf slab (4). The prefabricated exterior wall outer leaf slab (2), the prefabricated exterior wall insulation layer (3), and the prefabricated exterior wall inner leaf slab (4) are distributed from the outside to the inside. The surface of the prefabricated outer wall leaf plate (2) is reserved with a beveled tongue and groove (8), and the outer surface of the prefabricated outer wall leaf plate (2) is reserved with a groove (11). The surface of the groove (11) is covered with alkali-resistant mesh cloth (10). Water-swellable waterstop strips (7) are embedded on the outer side and both ends of the prefabricated outer wall inner leaf slab (4); Metal ventilation and drainage devices (9) and PE rods (5) are placed at the joints of the two sets of prefabricated exterior walls; the metal ventilation and drainage devices (9) include metal conduits (901) and gravel and sand wrapping bags (902). The joint between the metal conduit (901) and the prefabricated exterior wall is sealed with silicone weather-resistant sealant (6).
2. The anti-seepage and anti-cracking structure at the joint of the sandwich insulation board exterior wall according to claim 1, characterized in that: The metal ventilation and drainage device (9) and PE rod (5) are constructed after the main structure has settled and stabilized.
3. The anti-seepage and anti-cracking structure at the joint of the sandwich insulation board exterior wall according to claim 1, characterized in that: The groove (11) has a depth of 8-10mm, and the outer surface of the groove (11) is covered with alkali-resistant mesh cloth (10) and coated with waterproof and crack-resistant mortar.
4. The anti-seepage and anti-cracking structure at the joint of the sandwich insulation board exterior wall according to claim 3, characterized in that: The application of the aforementioned silicone weather-resistant sealant (6) is carried out after the application of the alkali-resistant mesh fabric (10) and the waterproof and crack-resistant mortar.
5. The anti-seepage and anti-cracking structure at the joint of the sandwich insulation board exterior wall according to claim 4, characterized in that: After the alkali-resistant mesh fabric (10) is constructed, a caulking seam is cut out and caulking is performed to ensure that the caulking area is exposed outdoors, and the silicone weather-resistant sealant (6) is an exposed seam.
6. The anti-seepage and anti-cracking structure at the joint of the sandwich insulation board exterior wall according to claim 1, characterized in that: The oblique tongue and groove (8) is designed with an inner high and an outer low.
7. The anti-seepage and anti-cracking structure at the joint of the sandwich insulation board exterior wall according to claim 1, characterized in that: The water-swellable sealing strip (7) expands and deforms 2-3 times when it comes into contact with water, filling all irregular surfaces, cavities and gaps in the joint, and generating huge contact pressure to completely prevent leakage.
8. The construction method of the anti-seepage and anti-cracking structure at the joint of the sandwich insulation board exterior wall according to claim 1, characterized in that: The steps are as follows: Step 1: In the detailed design and production stage, prefabricated exterior wall bevel joints (8) and grooves (11) are set at the junction of the prefabricated exterior walls. Step 2: Before hoisting the prefabricated components of the exterior wall, the outer side and both ends of the exterior wall are sealed with water-swellable sealing strips (7); Step 3: After the prefabricated exterior wall components are hoisted and the main structure has settled and stabilized, clean up the rubble and debris in the joint cavities; Step 4: Place a metal ventilation and drainage device (9) and a PE rod (5) at the seam. Step 5: Adhere alkali-resistant mesh cloth (10) to the groove (11) and apply waterproof and crack-resistant mortar, with the same thickness as the groove (11); Step 6: Locate and mark the seam positions, use a cutting device to cut the seam to the designed width, clean the area again, attach sponge strips along both ends of the seam and apply adhesive.