"Preventing Rainwater Leaks"
Technology for Maintaining Consistent Waterproofing,
Regardless of the Skill Level of Exterior Installation Technicians

Many different exterior products make daily life more convenient and coordinate your home’s elements, whether its appearance or the building structure, including its balcony, terrace, carport, and fencing. These products are generally assembled on site by installation technicians, and the inevitable discrepancy in technicians’ skill levels has posed an issue. In particular, the installation technician’s experience, the work environment, and the materials used can all affect the waterproofing quality of the sealant needed to maintain watertight performance. A defective sealant can cause various issues, such as rainwater leaking through a terrace or carport, or water leaking into the balcony handrail frame, leading to structural deterioration. For this reason, YKK AP has developed technology for “sealant-less on-site installation.” Our easy-installation products promote consistent, long-lasting quality, with simple on-site installation that doesn’t depend on the skill level of installation technicians.
We have developed “sealant-less caps” for the joints between components on carports and other structures. This unique waterproofing material maintains its adhesive strength over time and demonstrates effective waterproofing, with simple installation on site. Another problem requiring resolution: When a carport shakes in extremely high winds or an earthquake, the joints between components shift. This can lead to water leakage if the adhesion fails, creating gaps. Our waterproofing products therefore use materials that adapt to movement, allowing for long-lasting effective waterproofing.

For balcony handrails, we have developed a waterproofing material that replaces sealant but still prevents water from leaking into the handrail frame. For balconies at typical wooden houses, waterproof sheeting is wrapped around the frame. When screws are used to affix the holder and other handrail components, they make holes in the waterproof sheeting that protects the frame. Conventionally, sealant is required to seal those holes. But the waterproof material we developed is made of rubber and is tightly sandwiched between the holder and the waterproof sheeting. Tightening the cylindrical screws prevents water from entering the frame. We also took into account modifications that may be required on site, such as changing the position of components installed by a technician. We made a point of using rubber materials to ensure that the waterproofing does not deteriorate even if the screws are re-tightened multiple times.