FAQs

Frequently Asked Questions



Since the vent is installed between the concrete foundation and the sill plate, the whole house sits on the vent, will it crush?

No, it will not crush, the vent is made of a composite material that consists of calcium carbonate, polyolefin resin and recycled plastics. It has a compression strength of 1531 psi where wooden sill plates will begin to crush at 625 psi. So, the vent material is 2.5 times stronger then the wooden sill plate.


I see the holes in the vent are fairly large can bugs get in it?

The holes in the vent are 6.2mm or ¼” in the smallest dimension, which is what the actual IBC code states as acceptable. The vent is just the first part of the Joto Vent System we also have a custom piece of covering / flashing that is installed over the vent when the exterior siding is installed. This covering has 1/8” holes in it and that is because some building jurisdictions like to see 1/8holes to keep the bugs out.


Is this a brand-new product on the market, has it been tested?

The Joto Vent Systems has been certified for use in the USA since January 2015, but it has over a 45-year track-record of successful use in Japan. The Perimeter Vent System is the most common way crawl space / foundations are vented in Japan, and The Joto Vent System has over 60% of the market share. This is about 4.5 million homes that the Joto Vent Systems has been successfully installed on. 


Is this a green product?

YES, it is a green product, it has a recycled plastics content and when used properly you can collect Built Green points for construction projects. Since the vent is installed between the concrete foundation and the wooden sill plate, by code since the sill plate is not in direct contact with the concrete, it does not have to be treated lumber. Therefore, when you use the Joto Vent System you can eliminate all the treated sill plates off the job site giving you more build green points for your project. 


How many sizes does it come in?

The Vent come in 2 sizes, 4” wide for 2 x 4 framing and 6” wide for 2 x 6 and 2 x 8 framing. The covering / flashing comes in 1-3/4” (45mm) depth (protrusions) from the wall in white only. This comes in our Architectural Series 28 gage galvanized steel and in our Premium Series 17 gage Alum.


How does it perform during earthquakes?

This perimeter venting system was invented in Japan, where they used the same type of vents installed in the concrete as is used in the USA, because the weak point in the foundation is where the concrete vent box is located during an earthquake. This is why the Joto Vent system sits on top of the foundation wall and not set into the concrete, to keep the strength of the concrete foundation wall. We have also done shear wall tests to prove that the wall is just as strong with Joto Vent as it is without the vent.


Can I use this ventilation system on my current house?

NO, this vent is for new construction or new additions only. It must be installed under the sill plate so it cannot be retrofit into an existing house.


Can this system be only used for crawl spaces ventilation?

NO, it can be used are the inside of the garage as well with our special AIR BLOCKING plugs installed in it to prevent air flowing from the garage to the crawl space. It is added here or in other locations on the foundation wall to keep the same sill plate and stud height the same all around the foundation. Also, can be used to separate the sill plate from the concrete so you can eliminate the treated sill plate and use just a standard sill plate.


How difficult is it to install?

This installation has a very quick learning curve. Since there are 2 parts to the system, you will have to install them at 2 different times. The framers install the Vent, comes in 3-foot sections, before they install the sill plate. Then a few weeks later when the siders are ready to install the exterior siding the second part of the system is installed, the vent covering / flashing, comes in 10-foot sections.


What are some of the differences and benefits of this Joto Vent System vs the current concrete or rim joist vent boxes?

For the builder one of the biggest benefits is that the complete perimeter of the crawl space is being vented instead of just the corners and every 8-10 feet of the foundation walls. This gives you a much better cross ventilation which leads to better moisture management in the crawl space, thus prolonging the life of the wood under the house. For the engineer one of the biggest benefits is they no longer have to calculate the loss of strength in the foundation due to the vent box holes in the structural concrete or rim joist. As for the architect, the biggest benefit is the overall finished clean look of the exterior of the house with NO visible vent boxes. And for the home owner, all of the above, plus the confidence that their crawl space will be vented with the best ventilation system every designed.

Back to Top