How to solve the problem of rainwater leakage in doors and windows
Doors and windows are essential "equipment" for home decoration, but it is common for doors and windows to have rainwater leakage, and it has become one of the most common defects in door and window projects.
Analysis of the causes of leakage of exterior aluminum alloy doors and windows
1. Design reasons:
(1) The drip strip is not designed according to the specifications, and the spacing between drainage holes is too large;
(2) The design of aluminum alloy door and window rods is unreasonable, the rod stiffness or strength is insufficient, and it is easy to deform under wind load after installation, resulting in insufficient air tightness or water tightness and leakage.
2. Construction reasons:
(1) There is no gap between the aluminum alloy window frame and the wall, and the gap is not sealed with waterproof sealant, resulting in leakage at the cracks between the outer window frame and the wall;
(2) The screw holes for installing the aluminum alloy window and the assembly parts of the vertical and horizontal window frame components are not sealed with waterproof sealant;
(3) The aluminum window is not equipped with drainage holes or the drainage holes are too small, and the drainage holes are blocked;
(4) Defects in the production of aluminum alloy doors and windows:
a. When the aluminum alloy window is manufactured and installed, the splicing gap itself becomes a channel for water seepage;
b. The gap between the window frame and the wall of the opening is not filled tightly, and the outer side of the gap is not sealed with sealant. Under the action of wind pressure, rainwater seeps into the room along the gap;
c. The water retaining plate on the inner side of the sliding channel under the sliding window is too low, and the wind blows rainwater back;
e. The overlap of the casement window is not good, and the rainwater backflows under the action of wind pressure;
f. The window lintel and window sill are improperly made, without leaving a hawk mouth, drip groove, and slope, so backflow occurs.
3. Material reasons:
(1) The selection of aluminum alloy materials does not meet the design requirements and the rigidity is insufficient;
(2) The sealing material is of poor quality and is prone to aging and deformation.
Measures to prevent leakage of external wall aluminum alloy doors and windows
1. The lower frame of the aluminum alloy window must have a drainage structure:
(1) Sliding window: The guide rail is milled with an 8mm hole near the two frame positions for drainage;
(2) Casement window: Each fan hole is milled with an 8mm wide hole for drainage near the middle stile of the frame.
2. During structural construction, the size of each side of the door and window opening should be 20mm smaller than that of each side of the window frame, and polyurethane PU foam glue should be used to fill it tightly; it is advisable to paste high polymer self-adhesive joint tape at the junction for sealing;
3. A 5mm wide and 8mm deep groove is left between the aluminum alloy window frame and the surrounding wall decoration layer. After cleaning, it is sealed with waterproof sealant;
4. The height difference between the inner and outer window sills of the aluminum alloy window is >20mm, the outer window sill should be lower than the inner window sill, and the outer window sill should have a 20% outward drainage slope to make an eagle beak and a drip groove on the window lintel;
5. Use polymer fiber waterproof mortar (dry hard) to fill the gap between the aluminum alloy window frame and the opening wall, and then seal it with high-quality waterproof sealing materials. It is advisable to apply polymer self-adhesive joint tape at the junction for sealing;
6. The mortise and tenon joints, rivets, sliding supports, square grooves, screws, and other parts of the aluminum alloy window frame, as well as the gaps on both sides of the combined window frame rods, should be sealed tightly with waterproof glass silicone;
7. Replace the lower slide of the low-side water retaining board in the aluminum alloy sliding window frame with the lower slide of the high-side water retaining board.