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Products
Perimeter Vent System
The Joto-Vent System is a new system for the US market, however, it has been used successfully in Japan for the past 50 years and it is their standard for crawl space ventilation.
As of May 2019, we have received our ICC certification under ICC-ESR-4161 and is accessible on the ICC website. And it can be accessed here: ICC-ES report.
As of May 2019, we have received our ICC certification under ICC-ESR-4161 and is accessible on the ICC website. And it can be accessed here: ICC-ES report.
The Joto-Vent system is a unique method for crawl space ventilation that is new to the US, but a traditional Japanese construction method. This system was invented to protect against the Japanese climate in addition to earthquakes. Joto Techno has worked on inventing and expanding this system since 1974.
As of 2023, the Joto-Vent System was used on more than 4.7 million buildings in Japan. Today, 80% of new residential houses in Japan use a perimeter vent system, and regarding perimeter venting systems, Joto Techno holds a 60% market share in the Japanese market.
Features
Enables Ventilation
By installing the Joto-Vent System around the perimeter of the concrete foundation, you get a positive/negative airflow that allows moist, damp, and stale air in the crawl space to be exchanged with fresh air from outside. This leads to a healthier more suitable environment.
Preserves Structural Integrity
By using the Joto-Vent System, you no longer need to cut holes in your rim joist or form vent boxes in your concrete foundation. So, you can maintain the structural integrity of the foundation and rim joist.
Eco-friendly
The Joto-Vent sits on top of the concrete foundation and under the sill plate, thus the sill plate is NOT in direct contact with the concrete thus per IBC code, the sill plate does NOT have to be treated lumber. Hardware, therefore, does not have to be treated/galvanized as well. This is a great cost-saving and allows you the builders to apply for more BUILT GREEN points.The Joto-Vent System also gets BUILT GREEN checklist points for moisture control and airflow efficiency. This, when used in conjunction with other environmental and healthy house building practices assures the builder of BUILT GREEN points on every project.
Overview
We have spent a lot of time and effort to make sure the Joto-Vent System meets and exceeds all the IBC and IRC requirements for crawl space ventilation and moisture control. The Joto Vent System can be installed using two main methods: Vent & Architecural Covering (integrated ventilation and insect prevention flashing allowing for a clean architectural channel appearance along the bottom of the home) or Vent & Z flashing with Insect prevention flashing (JIP/KIP.)
Joto-Vent
It is installed on top of the concrete foundation and under the sill plate.
Custom Z Flashing
It is the Z flashing to cover the vent and insect prevention flashing, allowing for extended siding profiles and other building methods.
JIP/KIP (Ventilation and Insect Prevention) Flashing
Meets all code requirements for insect prevention and exceeds the performance of traditional vent boxes, which easily corrode and allow for lager animals to enter the crawl space. JIP Flashing is for the 2×6 Joto-Vent System while the KIP Flashing is for the 1×6 Joto-Vent system.
Installation Option
Option 1
Z-Covering (Optional)
The Z-Covering is a galvanized steel plate conforming to ASTM A792 called “galvalume”. With a 1-inch protrusion, it can maximize the ventilation performance of the 2x6 Joto-Vent.
Insect Prevention Strip
The Joto-Vent Insect Prevention Strip is a galvanized steel plate conforming to ASTM A792 called “galvalume”. It has a minimum opening of 1/8 inch, which provides efficient underfloor ventilation while also providing an insect prevention. By combining with Z-Covering with smaller protruding dimensions (sold separately), it can minimize the impact on the aesthetic appearance while preventing deterioration of the bottom edge of the siding. This Insect Prevention Strip is ICC-ES approved.
2 x 6 Joto-Vent
The primary component of the Joto-Vent is a molded calcium carbonate and polyolefin resin composite. The Joto-Vent is placed between the concrete foundation wall and the wooden sill plate to provide natural airflow around and through the entire perimeter of the crawl space. The Net-Free Ventilation Area (NFVA) is 11.03 in²/ft. When installing, leave at least 1 inch of clearance between the foundation and the siding or the back of covering to avoid blocking underfloor ventilation. By cutting this product and placing it sideways, it can prevent the cross-bending issues of the sill plate that may occur in the dropped floor application. By placing it into the space for the anchor bolts, it will also function as the Reinforcement-block against vertical load. (Contact us for details or our supporting letter for engineers.)
Option 2
Architectural-covering
One of the components required for the Joto-Vent System®. The Joto-Vent Architectural Covering is a galvanized steel plate conforming to ASTM A792 called “galvalume”. It acts as the cover for the Joto-Vent and the seat for the exterior wall sheathing. By installing it to the bottom edge of the wall, it acts as a drip edge to prevent deterioration of the siding. The slat opening on the back side plays a role as an insect prevention, the minimum opening is 1/8 inch, and it is approved by ICC-ES.
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Option 1
Z-Covering (Optional)
The Z-Covering is a galvanized steel plate conforming to ASTM A792 called “galvalume”. With a 1-inch protrusion, it can minimize the impact on the aesthetic appearance.
Insect Prevention Strip
The Joto-Vent Insect Prevention Strip is a galvanized steel plate conforming to ASTM A792 called “galvalume”. It has a minimum opening of 1/8 inch, which provides efficient underfloor ventilation while also providing an insect prevention. By combining with Z-Covering with smaller protruding dimensions (sold separately), it can minimize the impact on the aesthetic appearance while preventing deterioration of the bottom edge of the siding. This Insect Prevention Strip is ICC-ES approved.
1 x 6 Joto-Vent
The primary component of the Joto-Vent is a molded calcium carbonate and polyolefin resin composite. The Joto-Vent is placed between the concrete foundation wall and the wooden sill plate to provide natural airflow around and through the entire perimeter of the crawl space. The Net-Free Ventilation Area (NFVA) is 4.81 in²/ft. When installing, leave at least 1/2 inch of clearance between the foundation and the siding or the back of covering to avoid blocking underfloor ventilation.
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Reinforcement-block(Optional)
The primary use is to provide more reinforcement against the compression point at the foundation where a heavy vertical load from a post is applied. Consult with a structural engineer for advice on how best to use the block.
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Airtight Joto-Vent
The KPK-N140U Airtight Joto-Vent is our improved design of the Joto-Vent Air-blocking. It is used to create an air barrier between the garage and crawlspace and also can be used for slab on grade and entry areas. Use of the Airtight Joto-Vent allows for continuous use of the Joto-Vent and consistent height around the entire perimeter of the foundation when used with the Joto-Vent. EPDM Foam strips and connectors on each end have been added to create an even tighter seal.
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Architectural-covering
One of the components required for the Joto-Vent System®. The Joto-Vent Architectural Covering is a galvanized steel plate conforming to ASTM A792 called “galvalume”. It acts as the cover for the Joto-Vent and the seat for the exterior wall sheathing. By installing it to the bottom edge of the wall, it acts as a drip edge to prevent deterioration of the siding. The slat opening on the back side plays a role as an insect prevention, the minimum opening is 1/8 inch, and it is approved by ICC-ES.
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