What We Do
What Does Ventana Do?
Ventana designs, supplies, and installs high performing curtainwall facade systems.
The facade is one of the major risk factors on any building, and the team at Ventana has a proven track record of taking the risk and delivering superior facade systems that guarantee long-term performance.
Ventana’s management team strives to get “hands on” with projects as early as possible. We welcome the opportunity to work through the design phase with developers, owners, architects and general contractors to help provide the best possible solution to fit your specific needs. Similarly, we understand the overall schedule is critical to a project’s success, and we pride ourselves on our ability to complete quality projects in time frames that our competitors find daunting. Our network of system designers and engineers is second to none. We offer visually stunning façades while maintaining a great system performance, without compromising budget or schedule.
Design Assist Services
Ventana specializes in and offers design assist services to our customers. The design assist process has proven to be very effective in mitigating the risk posed by complex design requirements, and the use of emergent materials and specialized technology. Design assist is essentially a method to involve the necessary specialty expertise as early as possible in the design process. A compelling reason to embrace a design assist strategy is that it greatly facilitates fast track delivery and schedule acceleration, while removing waste and redundancy from the procurement process. The design assist contracting method is a key component in a broad, integrative process evolution that is bringing fundamental change to the building industry, and Ventana has deep experience with this methodology.
Traditional Bid Services
Ventana offers budgeting services in addition to hard bidding. Ventana can also assist with scheduling, phasing and logistics plans, as well as installation procedures.
Quality Fabrication and Installation
The Ventana team is devoted to quality fabrication and installation of glass products and framing systems in virtually every architectural application, including new construction, building rehabilitation, tenant interiors, and custom specialty work. Through quality workmanship, on-time project completion and trusted relationships throughout the country, our team of professionals has a strong reputation as one of the top glazing contractors in the nation.
Ultimately, structural glass facades are as much about the expression of elegant and minimalist structural systems as they are about facade transparency. The facades completed to date are easily categorized by the structural system types used to support them. However, a review of the completed projects representative of each system type will reveal a remarkable diversity of application. Ventana has the capability to develop any variation of these system types in response to specific project requirements.
Ventana Design-Build Systems has developed a complete line of custom high performance exterior cladding systems and products for use in the commercial contract glazing industry.
The base systems are designed around using common core elements to provide consistency and continuity between systems. All of the products are designed to be pressure equalized and rainscreened to the extent possible in order to maximize the system performance.
The main framing members and internal components are designed using standard metric dimensions to facilitate precision of fabrication in our off shore fabrication/assembly facilities, in addition to our domestic capability.
The primary airseal barrier in the system is located 40mm behind the exterior face of the mullion. This provides for a rainscreen cavity in the front portion of the vertical mullion; which is pressure equalized to the exterior. The increased separation between the rainscreen gasket and the airseal gasket provides enhanced performance against water intrusion.
Rainscreen cavity can also be used to mechanically support fins, brackets, and other components without penetrating the primary airseal.
Primary airseal gasket is also used at the stack joint, reducing number of different parts.
A Geon spacer is used eliminate metal to metal contact between male and female mullions; which will provide for silent movement under expansion and contraction.
Interior track system inboard of the airseal will be used to accommodate the structural mullion splices and a variety of anchor assembly options.
Vertical glazing trim is designed to be cut to length only (no notching required). The glazing side of the trim is in a flush plane, allowing the head, sill, and horizontal trim to also be cut to length only (no notching required).
The vertical glazing trim is also used at the stack joint, reducing number of different parts. A different trim part will be used if/when exterior caps are used.
Rainscreen gasket is designed to compress and remain symmetrical in appearance under the full +/- 3mm range of tolerance for the mullion assembly.
Typical horizontal is symmetrical. This will eliminate handed parts at corners.
Horizontal glazing trim is designed to snap into place without requiring any fasteners using the Z-Clips. This is designed to be installed from the exterior; and can be easily removed and reinstalled for re-glazing.
CW Stack Joint
Primary airseal line is set back 40mm from face of mullion to provide rainscreen cavity.
The Geon spacer is also used at the mullion, reducing number of different parts.
Head member is thermally broken using Z-Clips and PVC spacer. The top section with the Chicken Head is designed to extend over the top of the mullion without need for any machining.
Condensation or any other moisture which could develop within the stack joint assembly is collected within the lower condensation gutter and drained back to the exterior through the mullion in front of the airseal within the vertical rainscreen cavity.
Shadow Box Vs. Spandrel Panel
- Shadow Box should not be confused with a glazed spandrel panel.
- Key feature of shadow box is the air cavity behind external glazing.
- Commonly in spandrel panel application the insulation is butted up against the spandrel glass.
- A further difference is type of glazing used; shadow boxes generally use transparent glass, whereas glazed spandrels use opaque glass (painted, fritted, etc).
Why Use a Shadow Box?
- Shadow boxes are used for the particular appearance they give. The cavity behind the glazing adds depths to the appearance, creating greater visual interest than can be achieved with a more typical glazed spandrel.
- Allows the use of the same glass as used in vision areas, giving visual continuity between different zones of the façade.
To Vent or Not to Vent?
Un-vented Shadow Box Pros/Cons:
- Pros- Increase minimum cavity temp, no structural ban pans required, minimizes condensation, prevents dirt from entering cavity, can be used with face sealed systems.
- Cons- Increases max cavity temp, cannot be used with laminated spandrel glass, cavity pressures exist, cavity must be dry when assembled, humidity slow to dissipate, cannot be used with porous stone.
Vented Shadow Box Pros/Cons:
- Pros- Reduce max cavity temps, clears condensation, relieves internal pressures quickly, vents excessive humidity, can be used with laminated glass and stone.
- Cons- Reduces min cavity temps, may require structural back pans, introduces dirt into cavity, cleaning impractical, allows exterior humidity and fumes into cavity, condensation likely within cavity, cannot be used with face sealed systems, water/dirt marks possible.
Cost and Value Engineer Ideas?
$10-12 / SF approx. net added cost to furnish shadow boxes in lieu of typical spandrel glass
Value Engineer Options / ideas:
- Replacing the shadow box on upper floors and/or less visible areas with spandrel glass.
- Changing to a darker tint or reflective glass to reduce the variation between vision and spandrel.
- Accenting the spandrel area with reflective glass or metal panels
- These should be looked at on a case by case basis.
The rainscreen principle is a design concept that works to prevent the penetration of running or wind driven rain water through that part of a window or wall system exposed to the exterior. Pressure equalization is a method of making the pressure on both sides of the rain screen, the same so that rain water will not be sucked or drawn through the screen by pressure differences. A rain screen must be used to achieve pressure equalization and conversely pressure equalization will depend upon an effective rain screen.
In 1953, the Alcoa Building (now the Regional Enterprise Tower), become the first commercial building using the rainscreen principle. This is a 30 story tower in Pittsburgh using 1/8” aluminum panels with open, labyrinth joints.
In the early 1960’s, research was conducted in Norway on rain penetration of windows and walls. Mr. O. Birkeland published the first article referring to a “rain barrier”.
In Birkeland’s article he “suggested that venting the cavity behind the screen would equalize the pressure on either side of the screen and essentially eliminate air pressure differences as a rainwater penetration force.”
In 1971, the Architectural Aluminum Manufacturers Association (AAMA) published the first guide for pressure equalizing design.
The objective of a rain screen wall is to prevent rain penetration.
For wind driven rain to penetrate a wall assembly, three conditions must exist:
- There must be water on the outer surface of the wall,
- There must be an opening through which the water and air can pass, and
- There must be a force (like the wind), to push the water through these small openings.
If any one of these three conditions is eliminated, rain penetration will be significantly reduced or eliminated.
Rain water can penetrate the wall of a building in the following ways:
Capillary is the ability of a liquid to flow in narrow spaces without the assistance of, and in opposition to external forces like gravity. The forces involved are a combination of the surface tension of the water and the adhesive forces between the water and the adjacent materials.
Kinetic energy is generally referred to as wind-driven rain. Wind loads on buildings are subject to many variables including wind direction, gusts, building geometry, and surrounding conditions. This force is also the most associated with air pressure differences.
Surface tension is a contractive tendency of the surface of a liquid that allows it to resist an external force.
Gravity is the force that pulls water down the face of the wall and into openings.
Air currents are very much like the kinetic energy however without the wind-driven rain.
When one side of the cladding system has a positive pressure and the other side a negative, water will be pulled to the negative side.