Schweiss offers THREE different styles of doors and can speak truthfully about all of them, no sales pitch needed!

Hydraulic Door Myths And The Engineering Reality

Myth #1: “All Hinge Forces Are Even Across The Door.”

Easy Cop-Out: Reporting All Hinge Forces Are Even - Not True...

• To simply generalize the loads (spread evenly across all hinges) is practically useless, misleading and even dangerous.
• Some approaches generalize loads by assuming they are evenly distributed across all hinges. This is structurally inaccurate and can be misleading.
• Historically, engineers relied on simplified assumptions because detailed hinge load analysis was not practical. Today that is no longer necessary, because new analytical techniques are available.
• If the loads aren't accurate, the design isn't either.

A sophomore engineer can understand this is not the truth. It's like reading a fairy tale in the trees!

Engineers “Why Engineers Love Schweiss Doors' Specs.”

Feedback from building engineers supports the validity of Schweiss Doors' updated specification format for the following key reasons:

• Appropriate Level of Detail: Rather than relying on generalized assumptions (such as evenly distributed hinge loads), Schweiss provides individual hinge reactions, allowing for accurate evaluation of connection forces.
• Clear Graphical Representation: The use of isometric diagrams improves clarity and usability, enabling building engineers to readily understand and integrate door reaction forces into the overall building design.
• Comprehensive Load Case Coverage: All critical loading conditions are addressed, including:
  • Door Closed (Dead Load)
  • Door Open (Dead Load)
  • Windward Loading
  • Leeward Loading

This level of detail ensures that engineers have the information necessary to properly evaluate load paths and design supporting structural elements.

Why Schweiss Specification Sheets Matter

Understanding Hydraulic Door Loads - The Schweiss Advantage

Schweiss Doors is the leader in the development of hydraulic doors, building on their experience
from Bifold Doors. Schweiss has spent extensive time analyzing and developing “New Specifications and Reactions” of hydraulic doors that provide the forces that are transferred to the building framing.
It is critical that the customer pass these “Specifications and Reactions” onto the Building Designer.

Schweiss provides more than a door - we provide engineering clarity:

• Project-specific load calculations
• Hinge-by-hinge reaction data
• Code-compliant design information
• Clear, easy-to-understand documentation

Schweiss Doors is an industry leader in hydraulic door design, building on decades of experience with bifold and hydraulic systems. Through advanced engineering analysis, Schweiss has developed enhanced specification sheets that clearly define how hydraulic door loads are transferred into the building structure.

Understanding these forces is critical.

Schweiss provides the reaction data and load paths needed so building designers can properly integrate the door into the structural system.

New Technology Advancements

Advanced Engineering & Technology

Technology advancements now allow for quick and accurate analysis based upon the customer's requirements. Knowing the customer's local building code, overall door width and height, Schweiss is able to calculate the door and building reactions. This is done using iterative equations until a balanced solution is obtained. The process is quick, accurate and avoids the need to do a finite element model.

Modern advancements allow Schweiss to perform fast, accurate, project-specific analysis based on:

• Local building codes
• Door width and height
• Site-specific loading conditions

Using iterative engineering calculations, Schweiss determines:

• Door forces
• Hinge reactions
• Building interface loads

The process delivers a balanced and accurate solution without relying on overly simplified assumptions or unnecessary complexity.

Load Distribution

Accurate Load Distribution Matters

In order to ensure credibility with engineers and inspectors, believable loads must be reported.
To simply generalize the loads (spread evenly across all hinges) is practically useless, misleading and even dangerous.

Schweiss Provides: Individual hinge reactions for each load case:

1. Door Closed - Dead Load
2. Door Open - Dead Load
3. Windward Load
4. Leeward Load

As an example, for a hydraulic door, in load case 2. Door open dead load, there is virtually no load
on the center hinges. All the load is taken up by the first few hinges.

For engineers and inspects, credible load data is essential.
Some approaches generalize loads by assuming they are evenly distributed across all hinges.
This is structurally inaccurate and can be misleading.

Engineering Reality:

Load distribution is not uniform.

For example:

• Under door open dead load, center hinges may carry minimal load.
• End hinges and adjacent connections carry significantly higher forces.
• Accurate hinge-by-hinge load data ensures safe and reliable connection design.

Codes Changed

Designed for Current Building Codes

Specifications change over time; especially in regions where tornadoes and high winds are prevalent. New building codes like 2024 IBC are in place and enforced. Many regions, like Florida, require local complicance to their own codes (FBC 2023). Schweiss door specifications have been updated to comply with all the current building codes ensuring an efficient permitting process. Schweiss Doors accurately report all the code current detail needed to understand the building - door relationship.

Building codes continue to evolve - especially in high-wind and tornado-prone regions.

Schweiss specification sheets are updated to comply with:

• 2024 IBC.
• Regional codes such as Florida Building Code (FBC 2023).

Schweiss provides the code-compliant design data needed for:

• Efficient permitting.
• Engineering review.
• Structural coordination.

Easy Cop Out: Reporting All Hinge Forces Are Even - Not True...

Moving Beyond Outdated Assumptions

Historically assumptions had to be made regarding hinge loads; it was not technologically possible to report each hinge load. Even today, as a stop gap, some manufacturers assume an even hinge load distribution. New advancements using iterative equations now allow Schweiss to calculate each hinge load for the four load cases mentioned above. The new Schweiss specification sheets present the results in an isometric format making it easy for the building engineers to understand.

Historically, engineers relied on simplified assumptions because detailed hinge load analysis was not practical. Today, that is no longer necessary.

The Problem with “Equal Hinge Loads”

Assuming all hinges carry equal load is:

• Inaccurate
• Potentially non-conservative
• Not reflective of real structural behavior

The Schweiss Solution

Using modern computational methods, Schweiss:

• Calculates individual hinge forces
• Evaluates all critical load cases
• Presents results in a clear, isometric format

This allows engineers to:

• Understand load paths quickly
• Design connections with confidence
• Avoid hidden over-stress conditions

Bottom Line

Hydraulic doors introduce real structural forces into a building.

If the loads aren't accurate, the design isn't either.

Schweiss specification sheets give engineers the information they need to design with confidence and ensure long-term performance.

Myth #2: “An open one-piece hydraulic door does not put more stress on the building than other doors.”

NOT TRUE: Hydraulic doors, when in the open position, are like a large airplane wing hanging way out
there when in the open position, vulnerable to the wind! In the open position, a bifold door has half the surface area of a hydraulic door, and therefore less than half the wind load.

Do Not Believe Everything You're Told

Quote... A customer asked... “When the door is hanging straight out there, you better have something strong holding those cylinders. Doesn't that put a lot of stress on the building?”

Wind beats on the door in the open position - Can make the door flutter / vibrate / bounce / screws work loose on the door frame. The door better have strong hinges and a strong building to withstand the winds!

Easy for the wind to catch the open door frame, causing excessive stresses on your door hinges and building structure... Take into consideration the hydraulic door and its subframe connects/attaches to the building structure, so your building must support those forces

Hydraulic Doors in the Snowy Areas of the Country

Door acts as a snowplow as the door is opening, scooping the snow away with the external door
truss and exerting enormous forces onto the door frame structure & hinges and building structure.

Hydraulic Door

Snow that slides off the roof catches on the truss...
Now it's a problem!

Bifold Door

Snow that slides off the roof slides off the door and on to the ground...

External Truss on a Hydraulic Door

It is a real eye sore - needs constant maintenance / painting / tripping hazard / snow plows can damage
the bottom truss. It's in a bad location! If you put the truss on the inside of the door frame, you lose 1 ft.
of headroom.

Myth #3: “Bifold doors put more stress on your buildings compared to single-panel hydraulic doors.”

NOT a True Statement: Bifold doors fold in half when in the open position. Huge advantage! There is less area for wind to catch when door is in the open position. Schweiss new designed Strap Latch helps support the bifold door from wind in all positions while the door is opening... Nice feature that keeps the door tight against the door columns!

Hydraulic Door Forces Are Considerably Different From Bifold Doors.

Bifold doors roll up the face of the door side column, hydraulic doors cantilever from a fixed location on the cylinder bracket, which is offset inside and behind the door side column. Bifold doors fold as they open. Hydraulic doors open as one piece so the hydraulic door is cantilevered much further than the bifold door. The operator of the bifold door distributes much of the dead load of opening the door to the hinges. The hydraulic doors are opened using powerful hydraulic cylinders which concentrate the door opening loads at the cylinder bracket location on the building door side columns.

Subframe Alone Is Not Enough

Hydraulic doors definitely put more forces on your building, that's why hydraulic doors need a subframe to help lighten the hydraulic forces back to the building structure... the standard subframe alone is not strong enough to support the hydraulic door in the open position... The Hydraulic door is dependent on the building structure to hold the door place.

Common Sense: Bifold doors stick out half the distance. That's a huge advantage over hydraulic doors.
It doesn't take a rocket scientist to figure out that bifolds put less stress on your buildings when open. The bifold door buildings columns are designed to withstand the doors forces. Schweiss provides detailed Spec Sheets that explain it all!

Bifold Door

Hydraulic Door

Bifold doors lift straight up, bifold doors roll smoothly up the building column when opening. Bifold doors lift straight up, transferring the weight to the building header as the door is opening unlike a hydraulic door that pushes the door frame to swing outward. When the door is wide open, it's torquing / twisting force tends to cause rotation on the building structure... Bifold Doors are easier to support than Hydraulic Doors. A good engineer can explain the differences!

Redundancey Built In For Safety

Bifold doors are lifted with multiple lift straps rated at 29,000 pounds each. Example: a 40 ft. wide bifold uses four lift straps that evenly lift the door and distriubutes the weights evenly across the 40 ft. width. Larger doors come with more lift straps and another motor for added safety unlike a hydraulic door that only uses two hydraulic cylinders exerting all the forces at the ends of the door. Larger hydraulic doors continue to only have 2 cylinders up to spans as big as 130' - most people see “less moving parts” but safety oriented people see less redundancy in the event of a failure.

Internal Truss on a Bifold Door

A Clean Look - Internal trusses
are located inside of the door.

• No eye sore.
• No maintenance.
• No hazards.

Slight Slope

Water Runs Off

External Truss on a Hydraulic Door

Real Eye Sore - Needs constant maintenance, painting, tripping hazard, snow plows can damage the bottom truss. If you put the truss on the inside of the door frame, you lose 1 ft. of headroom.

90° When Open-Flat

Water damage may occur to insulation and hydraulic door if water rests on top of fully opened door.

Why No Subframe Required on a Bifold Door

Bifolds lift straight up when opening - even lifting with numerous lift straps, less stress, no subframe needed... Hydraulic doors are forced open by 2 cylinders that continue to open the door as it operates. The forces on a hydraulic door are much different and greater than a bifold door. Hydraulic doors REQUIRE the subframe - without it, the building would be under immense stress. Whereas the bifold does NOT require it - yet it can be included and is a great option for retrofits.

Myth #4: “One-piece hydraulic doors don't need additional header support.”

That Is Not True... all hydraulic doors require additional subframe that reinforces the building's header and columns. The subframe is standard and a must-have on all hydraulic doors - See the reason why!

Quote... A Engineer Once Said...

“No structure is infinitely stiff. If the sub-frame moves as the door is opening, it is putting load on the building. The prudent design manages both the sub-frame loads and the building loads.”

“The Doors Will Find the Weak Points in the building design. Many metal building engineers have a tendency to get lax with the design of the door supports and framing surrounding your doors and forget that you not only have to support the weight and wind on the door, you also have to support its operation.” *NOTE: “It's better to overbuild your building than to make costly repairs later.”

One-piece hydraulic doors, when in the open position, are held open by only two cylinders, one on each end of the door frame. The very outside hinges on a hydraulic door need to be extra strong to take the cylinder forces and the weights (Some manufacturers are out there repairing their outside hinges when they pull away from the subframe, unlike Schweiss Hinges) (Think about this “all hydraulic doors are lifted by two cylinders”) All the loads and forces are transferred back into the door frame and subframe by the hydraulic cylinders. Cylinder rods must be heavy or they may buckle under the weight / loads. This does not apply to bifolds. Schweiss provides heavier cylinders with spherical bearings.

Forces on Subframe and Hinges as the Door is Opening

The door transfers loads into the building as the door is opening... The quality of material and components used to build the door are important because the stress placed on the door and subframe while the door is opening are extreme.

As the cylinders push the door open, at the same time, the door is exerting huge forces on the very end hinges of the door frame. Schweiss robust hinges are designed to withstand all the cylinder forces. When the hinges are under designed they can pull off or out of the subframe header tube, which calls for the repair man to the job site, that can be costly!

*Not a Schweiss door

*Not a Schweiss hinge

This Door Was
Left Open in
a Storm... Destroyed The Hinge!

Everything “Hinges” on the Hinges!

Remember, a hydraulic door is only as strong as its weakest link. Hence, the hinges can undermine the entire system. Instead, opt for a hinge that's built to weather the storm, like Schweiss. Schweiss hinges are a promise of durability and a beacon of trust for your hydraulic doors, ensuring they never let you down.

When you invest in quality hinges like Schweiss, you're not just buying a piece of metal. You're investing in a secure future for your hydraulic door system. You're endorsing a safer, more efficient operation. You're prioritizing quality and safety over cost. After all, the longevity of your hydraulic door hinges is a direct reflection of their quality. Therefore, when it comes to hydraulic door hinges, quality should never be compromised. It's a necessity for safety, reliability, and overall peace of mind.

Smart Design

The Schweiss robust hinges are designed to withstand the door weights and hydraulic forces of the cylinders as the door opens. Your door is only as good as its hinges! Take one look at the Schweiss hinges and you will clearly see the workmanship, strength, and functionality of each hinge.

The Schweiss Hinges Are Big... Strong... & Heavy-Duty!

Myth #5: “No need to do anything with your ‘building’. Doors come with their own subframe.”

Hydraulic Door & Subframe:

Relies on the Building Structure for Additional Strength

• The horizontal subframe header and the moving door frame
  mounts directly to the buildings structures header.
• The hydraulic door and sub-frame header relies on a properly
  designed building structure for support!
• The building must have properly sized side columns and properly sized building header
  support to make a safe door installation.
• The vertical subframe that the cylinders attach to mount directly into the buildings side columns.
  The building side columns must be designed to support the door loads in all positions.

Others Like To Paint The Picture That The Subframe Is All You Need, Deceptive Play on the Subframe's Role

Facts:

• Others like to paint the picture that the subrame is all you need... NO!
• Hydraulic doors and their subframe “Do Not Stand Alone.”
• SUBFRAME DECREASES the door loads that hydraulic doors exert on your building structure.
• Hydraulic doors and their subframe require a properly designed building structure to attach the doors to.
• YES, the subframe shares the loads with the building structure. Schweiss provides the Door Specs, reporting the loads onto the building with every door! The subframe is a necessary feature on ALL hydraulic doors to DECREASE the door loads that hydraulic doors exert on your building structure.

BIFOLD vs HYDRAULIC LOADS

• Hydraulic doors exert more exorbitant loads to the building, Period.
• Hydraulic doors with subframes will exert more loads on a building than a bifold door.
• A good engineer will explain the difference between the forces of a bifold door vs hydraulic door. Schweiss provides the Door Specs reporting the loads onto the building with every door!

You must KNOW THE FACTS and KNOW THE LOADS on the door that will be repeatedly impacting every member of the door, its subframe, and your valuable building structure. These things fatigue like anything else, and if improperly desgiend, their life span can be extremelys hort; that leads to DANGER, DAMAGE, and FAILURE.

Bifold Door

Hydraulic Door

Myth #6: Get “Single source accountability”
with satellite welding shops.

The picture that gets painted is that there is a long track record of satellites manufacturing doors across the USA. What they don't tell you, is that the satellite you are buying from may be producing their first door. The last thing you want to hear as you are going under the knife is the surgeon saying this is my first operation. The satellite welding shops you're buying from may have just started a year ago, and only have one or two doors or more under their belt.

Single source accountability comes from a large door manufacturer who has the expertise and know-how, paired with 46 years of experience in the door industry. From start to finish, Schweiss is there to answer any questions and provide support and boots on the ground.

The ability to sign a licensing contract doesn't mean that the satellite welding shop can competently manufacture a door, and more importantly stay in business for years to service your door if needed. Many welding shops that fall under a license do not have years of experience and maybe only build one or two or more doors a year. That's not the “single source accountability” I'd sign up for.

Schweiss stands behind all their products from start to finish. Would you really want to buy your door from the “Rookie of the Year”? Or would you rather buy it from a company with 46 years of expeience manufacturing doors in the same location? Buy from Schweiss!

100' Door

Doors Ready To Ship

Loading a Container

Building More Doors
Every Day!

Door Manufacturing

Myth #7: “Local small branch satellite job shops offer better support.”

SCENARIO: Satellite door manufacturer has stopped manufacturing doors... When that happens, who services your door? What about your warranty? We have seen start-up satellite door companies manufacturing doors for awhile and for some reason or another they quit or lost their brand license...

Maybe they lost interest in manufacturing, maybe they were not producing enough. I'm sure there's many different scenarios... The question is how long will your door manufacturer be around and who's going to support your door! If they stop making doors, now you must search for replacement support!

Schweiss has ONE Manufacturing facility doing World Wide Sales. Schweiss has been manufacturing doors for over 46 years. That's a track record we are very proud of!

Find Out Where The Door Is Being Manufactured...

• How many years of door experience does the door manufacturer have?
• How many doors has this shop manufactured?

Who's Responsible For the Warranty of the Door

• Who will be responsible, and for what, if your door pukes out on you and you need service?
• Who can the customer call when in need of service? Avoid any possible run-around!
• Who will fix your door?
• Where will you be able to get parts?
• Who will honor the warranty, if any?

Sad But True...Over the years, there have been manufacturers that have stopped building doors for many different reasons...

• Perhaps due to low margins, poor cash flow or cash flowing to the wrong places?
• Who stands to lose the most when a door manufacturer STOPS manufacturing and repairing doors?...

Answer: The Customer!

We Are Not a Small Fab Shop
Building a Few Doors Here and There...

Schweiss delivers doors across the United States, Canada and World Wide. All manufacturing is done at one location for over 46 years. Schweiss supports their doors 24/7. When you call for support, we are able and willing to answer any questsions from sales to service. Schweiss has successfully been manufacturing doors for over 46 years, you can find Schweiss doors spread throughout the USA and more.

Schweiss offers 3 styles of doors. We know that certain doors work better in certain situations. So, no matter what style of door fits you best, let us build it!

Look For Quality, Look For Price, You'll Buy Schweiss!