The Original Ultra CSV Crawl Space Vent • Back by popular demand • Made in the USA • The Original Ultra CSV Crawl Space Vent • Back by popular demand • Made in the USA • The Original Ultra CSV Crawl Space Vent •

Frequently Asked QuestionS

Can I paint the Ultra CSV Crawl Space Vent before installation?

Yes. A plastic-compatible spray paint/primer is recommended. Prior to painting, mask off the stainless steel screen to maintain maximum airflow through vent afterward. Of course, it is not necessary to paint the back of the Ultra CSV outer frame, which will be hidden from view.

Please note that any painted Ultra CSV Crawl Space Vent cannot be returned for a refund. Contact Griff Invent, LLC at sales@ultracsv.com for replacement parts if necessary, and we will do our best to serve you.

Can I add insulation behind the solid seal plate?

Yes. For extra energy savings in the winter season, and year-round if the intention is crawl space encapsulation, insulation of your choice can be added between the cross bar and the solid seal plate during the cold season changeover. Store insulation pieces in resealable gallon-sized plastic bags during the warm season to keep them clean and dry.

What if the threaded rods included with the Ultra CSV Kit are too short?

First, make sure you have not extended the threaded rods too far through the front surface of the Ultra CSV outer frame. The threaded rods should only extend 1/2" to 5/8" beyond the front surface of the outer frame. Loosen the hex nuts and adjust, if necessary.

Reach inside the foundation vent opening and check for any mortar or portion of soft interior insulation that prevents the cross bar from resting firmly against the hard inside surface of the foundation wall. Remove it with a hammer and chisel or putty knife, then try again.

If the foundation wall thickness exceeds 8", you will need to purchase and cut two longer pieces of 1/4–20 threaded rod, at least 1-3/4" longer than the foundation wall thickness. 1⁄4–20 sized threaded rod is available at most hardware and home improvement stores.

Can I use wing nuts instead of hex nuts behind the cross bar?

Yes. Hex nuts are provided with the kit because they are generally easier to start onto a threaded rod from a reverse angle, but wing nuts may be used in their place to avoid the need for a 7/16" wrench to tighten the hex nuts behind the cross bar. Be sure to tighten the wing nuts until the cross bar is slightly bowed to ensure proper clamping and sealing of the Ultra CSV outer frame.

What if the Ultra CSV outer frame must slide up under sheathing and siding to fit properly?

On some homes with siding, where foundation vent openings are adjacent to the siding, the exterior sheathing and siding may need to be pried away from the sill plate about 1/8" to 1/4" for the top edge of the Ultra CSV outer frame to slide up under the sheathing. To do this, use a flat bar/pry bar and or wedges/shims to pry the sheathing away from framing and foundation. Be careful when prying. On some homes, the sheathing is very weak and brittle with age. Resecure all house cladding you may have loosened when prying.

What if the sheathing and siding are pried away and the Ultra CSV outer frame will still not slide far enough up under the sheathing?

Slide a putty knife or thin metal ruler up under the sheathing to determine where any obstructions may exist. These obstructions may be nails, screws, and other fasteners in line with the foundation vent opening. Mark the exact point of these obstructions on the siding. These obstructions may be addressed in two ways:

a. The fasteners can be cut using a hacksaw blade or jab saw, slid up under the sheathing.

b. Make a mark along the top edge of the Ultra CSV outer frame where it hits the fasteners. Also mark how close the fasteners are to the top edge of the outer frame if the frame were installed level and centered within the foundation vent opening. Using a jig saw, carefully cut a slot or “notch” in the Ultra CSV outer frame, perpendicular to the top edge, at each point where the fasteners hit the outer frame. Make the notches deep enough so that the outer frame can slide up under the sheathing and “around” the fasteners to fit level and centered within the foundation opening.

Remember: measure twice, cut once! Please note that any modified or cut Ultra CSV Crawl Space Vent cannot be returned for a refund. Contact Griff Invent, LLC at sales@ultracsv.com for replacement parts if necessary, and we will do our best to serve you.

What if the foundation vent opening borders an obstruction that cannot be removed or pried away, such as an adjacent inside corner or a brick ledge?

The Ultra CSV is made of ABS plastic and can easily be trimmed in height and/or width using any tool designed to cut plastic. The backside of the outer frame has pre-scored lines at the top to assist in customizing the height of the outer frame neatly and squarely.

A flush fit is a must, with the edge of the outer frame overlapping the foundation vent opening by at least 1/4" on all four sides. If the obstruction prevents a proper overlap of the outer frame with the foundation opening, cut a PVC or exterior trim 1 x 4 to the width or height of the vent opening and attach it adjacent to the obstruction to form a new 3/4" wide surface for the outer frame to overlap. Trim the Ultra CSV outer frame height and/or width as needed to fit level and centered within the newly formed foundation vent opening.

Similarly, if an adjacent sill plate overhangs or is recessed from the foundation wall surface, cut a PVC or exterior trim 1 x 4 the width of the foundation opening and attach it to the sill plate so that it is flush with the foundation wall to form a new 3/4" wide surface for the top edge of the Ultra CSV outer frame to overlap. Trim the outer frame height as needed to fit level and centered within the newly formed foundation vent opening.

Please note that any modified or cut Ultra CSV Crawl Space Vent cannot be returned for a refund. Contact Griff Invent, LLC at sales@ultracsv.com for replacement parts if necessary, and we will do our best to serve you.

What if there is a cinderblock installed sideways inside the foundation vent opening?

Foundations are designed and built by many different types of contractors. A small percent of contractors installs a cinder block (CMU) sideways in the foundation vent opening behind the crawl space vent. This cinder block can typically be removed with careful use of a hammer and masonry chisel. Removal will allow for normal installation of the Ultra CSV Crawl Space Vent and increase the air flow through the vent as well. If any doubt exists as to the structural support provided by the cinder block, consider checking with a contractor or local building inspector before removing it; however, most foundation vent openings span 16" and do not have cinder block supports within their span.

Remember: measure twice, cut once! Check to make sure that the foundation vent opening will accommodate the Ultra CSV before performing any irreversible demolition. Always wear safety glasses and appropriate face mask or respirator when performing demolition and debris removal.

Is caulk required when installing the Ultra CSV Crawl Space Vent?

No. When properly installed, the Ultra CSV will not come loose or fall out; caulk or adhesive is not required for a secure installation in most cases. Be sure to tighten the two hex nuts behind the cross bar until the cross bar is slightly bowed. A slight bend (tension) in the cross bar ensures proper clamping and sealing of the outer frame.

For a completely airtight perimeter seal, such as might be preferred in extremely cold climates and total crawl space encapsulation projects, a bead of silicone caulk can be applied to the back surface of the Ultra CSV outer frame within the border area that will contact the foundation wall. Do not use petroleum-based products, which can damage the ABS plastic outer frame.

Self-adhesive foam weatherstripping (available at most hardware and home improvement stores) can also applied around the back edge of the Ultra CSV outer frame prior to installation when a more airtight perimeter seal is desired.

What if the foundation vent opening is bigger or smaller than the size limits listed for the Ultra CSV Crawl Space Vent?

Ideally, the foundation vent opening should be within these size limits:

Minimum Width = 14-5/8"

Minimum Height = 7-1/8"
Maximum Width = 17"

Maximum Height = 9-1/2"

The cross bar is 18" long and must “bridge” or overlap the inside of the foundation vent opening on both ends to clamp the Ultra CSV outer frame in place. A minimum overlap of 1/2" on both ends of the cross bar is recommended, therefore 17" is the maximum foundation vent opening width recommended for a typical installation.

If the foundation vent opening is too large or too small, it may be necessary to frame the foundation opening to create a new Ultra CSV mounting surface. Two ways to address this are:

a. If the foundation vent opening is too small for the Ultra CSV outer frame indention to fit inside, one option is to frame around the foundation opening with 1 x 2 or 1 x 4 PVC or exterior trim fastened to the front of the foundation wall. The inside of the new frame should be large enough to accommodate the Ultra CSV outer frame indention (14-5/8" x 7-1/8" minimum). The outer edges of the new frame surface should extend past the edges of the Ultra CSV outer frame (19-1/2" x 10" or larger).

b. If the foundation opening is too large, one option is to fasten lengths of 1 x 4 PVC or exterior trim to the inside of the foundation opening to reduce the width and/or height of the foundation vent opening as needed to create a narrower and/or shorter mounting surface for the Ultra CSV outer frame. A longer cross bar can be fabricated from 1 x 2 PVC plastic trim, if necessary. The distance between the two holes in the Ultra CSV cross bar is exactly 13-5/8".

What if my foundation vent opening has a floor joist, duct work, or other obstruction behind it that will not allow for a normal installation using the cross bar?

If interior floor joists or support beams, duct work, or other obstructions are behind a vent opening and will not allow for a normal Ultra CSV installation using the cross bar, these obstructions may be addressed in several ways:

a. First, always clear out as much of the foundation vent opening as possible to provide the maximum amount of air flow. If one cannot use the threaded rods and cross bar due to limited space, try replacing the threaded rods with 1/4–20 bolts and 2 x 2 wood cleats (or L-brackets) fastened to interior floor joists or support beams. The distance between the threaded holes in the Ultra CSV outer frame is exactly 13-5/8". Maintain this distance between any improvised bolts to insure proper clamping and alignment with the Ultra CSV outer frame. Do not neglect to install two hex nuts against the back of the Ultra CSV outer frame to prevent loosening of the improvised 1/4–20 fasteners when removing the ventilation door caps and rivet nuts for summer/winter changeover.

b. Depending on the mounting surface, use wood screws, concrete fasteners (such as Tapcons®), or Molly bolts and lay out a series of four points at which to drill holes through the Ultra CSV outer frame and fasten the outer frame directly to the foundation wall from the front. Secure the outer frame to the foundation wall, then proceed with the vent installation as usual using shorter 1/4–20 bolts or rods threaded into the outer frame from behind, in place of the threaded rods. Follow the fastener manufacturer’s instructions carefully when drilling into the foundation wall. Stainless steel or rust-resistant fasteners are recommended when performing this type of installation.

Non-petroleum, silicone caulk can always be added to the back side of the outer frame before installation for a more secure, airtight installation.

Is a building permit required to install the Ultra CSV Crawl Space Vent?

Based on most residential building codes and conversations with several inspection departments, it is our opinion that a building permit/builder’s license is NOT required to install Ultra CSV Crawl Space Vents. This activity falls within the definition of an "ordinary repair". While it should not be necessary, if installing the Ultra CSV Crawl Space Vent requires “cutting away of any wall, partition, or portion thereof, the removal or cutting of any structural beam or bearing support, or the removal or change of any required egress,” a building permit and/or license would likely be required. A copy of an attorney’s legal opinion on this matter (from Traverse City, MI) is available upon request.

Do you still have white solid seal plates as were included with the Ultra CSV Crawl Space Vent in years past?

No. We feel a black solid seal plate is more aesthetically pleasing and disappears when installed. If you prefer to have white solid seal plates to match any older Ultra CSV units, white seal plates can be easily fabricated from 1/8" thick PVC or HDPE plastic sheet available from most craft stores and from multiple sources online. The rectangular solid seal plates are 13-5/16" x 6-5/8".

Alternately, you can purchase black solid seal plates separately from Griff Invent, LLC to replace your old, white solid seal plates. Contact us at sales@ultracsv.com for replacement seal plates, and we will do our best to serve you.

Are Ultra CSV Crawl Space Vents guaranteed?

Yes! Ultra CSV is guaranteed—period. If you believe an Ultra CSV Crawl Space Vent did not perform to your expectations, contact Griff Invent, LLC at sales@ultracsv.com, and we will do our best to serve you. Please note that any painted, modified, or cut Ultra CSV Crawl Space Vent, or any Ultra CSV Crawl Space Vent damaged by excessive impact, vandalism, or force majeure, cannot be returned for a refund.

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