A Look at Passive House Doors

What Are Passive House Doors?

A Passive House door is an exterior door specifically designed to help homeowners meet the rigorous Passive House standard for energy efficiency and thermal performance. Passive House doors resemble a vault door. They are at least four inches thick and have multiple gaskets and latches to ensure maximum sealing. When you close a regular door, you can hear the door latch closing. With Passive House doors, however, a clear and distinct sealing sound is detectable upon closing.

Besides being much thicker than regular exterior doors, a Passive House door also has better insulation with a much improved R-value. This feature helps to lessen or even eliminate the thermal bridging that occurs through your home's exterior doors.

Specifically, doors that meet the international Passive House standard will have highly advanced energy efficiency features, including:

• Three or more locking points along the edge of the door frame
• Three seals between the door and the frame
• Two seals along the bottom
• Highly insulated body with at least R-10 insulation, twice as good as a standard door
• If the door contains glass, it will be triple glazed with argon or krypton gas-filled spaces between the glazing.

What Types of Passive House Doors Are Available?

It is essential to recognize that there are no specific certification criteria associated with passive house doors. If you find a manufacturer or a store selling a "Passive House-certified door," they are probably referring to the fact that the door meets the insulation and airtightness requirements necessary for a home to be certified as a Passive House. The specific requirements will depend on the climate where construction takes place.

However, most Passive House doors will be "graded" by their U-Factor, or insulating capability as a general rule of thumb. According to the US Department of Energy (DOE), the U-factor is the rate a window, door, or skylight conducts non-solar heat flow, generally measured in Btu/hr-ft2-°F.  

For doors, the lower the U-factor value, the more energy-efficient the door will be. Passive House certified doors (including those doors that have window inserts) typically have a U-factor of 0.14 Btu/hr-ft2-°F or less.

How Much Energy Do Passive House Doors Save?

Most people associate heat loss or unwanted heat transfer in the house with poorly insulated walls, attics, and ceilings. Insufficient insulation will undoubtedly drive up your energy costs. However, air leaks around windows and doors are another major contributor to wasted energy in the home. 

Heat loss through doors also occurs via heat transfer mechanisms such as conduction and convection. The heat will move through the solid door parts such as the jambs, panels, sill, and rails with conduction. With convection, heat is lost due to air movement in the small spaces between the door and the frame.

Passive House doors are specifically designed to improve energy efficiency and thermal performance by reducing air leakage and heat transfer. The actual energy savings will depend on the type of door that is being replaced. However, the combination of low U-values, high insulation R-values, triple glazing of glass, zero thermal bridges, and complete airtightness will almost certainly lead to energy savings.

How Long Does A Passive House Door Last?

Most people consider installing a passive house door to decrease air leakage or thermal bridging as part of a more comprehensive energy efficiency retrofit. However, another benefit of these doors is that they are significantly sturdier, longer-lasting, and more durable. The hardware used by the doors has a locking lever mechanism with multiple latches and locks. These features help compress the numerous gaskets and seals to ensure airtightness and offer added security for the home. The thickness of the doors (at least four inches) also guarantees more durability. In most cases, a Passive House door will last for a lifetime.

How Do You Install a Passive House Door?

Because Passive House doors come with several different latches and seals, installation generally requires a professional. Without correct installation, the magnetic and compression seals may not bond correctly, compromising the expected energy efficiency benefits. As a general rule of thumb, if you do not hear these components latch when the door closes, something is wrong with the installation.

Advanced engineering and design go into the construction of Passive House doors. One example is the flexibility of adjustment. They have four hinges and three locking points, and the installer can individually adjust each hinge and locking point. If your house shifts a little over time, as homes tend to do, the door can be adjusted so that it continues to seal appropriately. Thoughtful touches like this make these doors a cut above the rest and are an integral aspect of adaptable design or building a home that lasts for a lifetime.

What Are The Best Brands of Passive House Doors?

Searching for a suitable Passive House entry door can be tricky. In the United States, the energy efficiency criteria for doors are set by the ENERGY STAR Program. ENERGY STAR-certified doors, however, allow for higher U-factors than the level that Passive House doors require. One way to search for Passive House doors is to check the variety of suitable Passive House Certified products visible on the Passive House Institute Component Database. You can see a complete list of Passive House certified doors manufactured around the world at this link.

Though many of the best Passive House doors are manufactured in Europe, there are a few North American manufacturers of Passive House doors. Cal Doors make the doors that can be purchased through Vetta Building Technologies in Canada. Other companies offering Passive House doors certified by the database mentioned above include Cascadia Windows and Doors and Fenstur Windows out of British Columbia. Neuffer Windows is another world-recognized leader in passive house doors, based out of Germany.