Category: Design Break

Design Break is a monthly solution for thermal bridging. Each month will focus on different application and types of the Isokorb thermal break element.

12. March 2015

Around the Corner Balcony

from Alexander Krenczik


Condominiums and apartment buildings can be designed with corner, wrap around balconies to provide dramatic views. These corner balconies are most commonly cantilevered concrete balconies which are a slab extension from the building’s interior slab surface.

Corner balconies provide heightened aesthetics designs as well as ensure optimal sun exposure on the balcony. This is especially important when your balcony faces east, to allow a corner section on the south to provide additional sun exposure during the day. In dormitories, balconies are often used as loggia walkways around the building as an evacuation scenario for a fast and secure escape.

Building with Wrap around Corner Balconies.
Building with Wrap around Corner Balconies.

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04. November 2014

The Intersection of Glazing Systems with Structural Thermal Breaks

from Mike Lemen

Architects and Engineers often ask about the design considerations when the connection of the window wall glazing system closely intersects with the structural thermal break connection at the balcony.


Balcony window and thermal bridge connection

This Design Break will take a look at the considerations when preparing the details of the glazing system with a structural thermal break connection for concrete, such as you see in the J22 project in Edmonton. … read more

24. July 2014

Cantilever Slabs at Stairways and Shafts

from Matt Capone

Normally cantilevered slabs and edges are considered extensions of the floor or roof levels of a structure. Often times however, conditions require a connection along vertical walls or areas where interiors floors are omitted because of stairways or mechanical shafts. These areas have the same potential problems with thermal bridging since there is an interruption in the continuous insulation layer.

For this Design Break, we explore details of a project in which Isokorb® thermal breaks were used in just such conditions, 15 Leonard Street located in the Tribeca neighborhood of New York City.

15 Leonard
15 Leonard: Exterior rendering of the rear façade showing the balconies tucked to the inside corner


Architectural floor plan showing the slab openings for the stairs and mechanical shaft – both located adjacent to portions of the residential balcony.
Architectural floor plan showing the slab openings for the stairs and mechanical shaft – both located adjacent to portions of the residential balcony.

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04. March 2014

Exterior Steel Beams that Break Thermal Bridging

from Adam Kimble

Steel is the most popular framing material for non-residential buildings in the US. As the AISC’s slogan goes, “There is always a solution in steel.”  It is sustainable and readily available, strong in both compression and tension, and allows acceleration of project schedules making it a cost effective construction option.

Canopy steel structure

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24. October 2013

Earthquake Considerations for High Performance Cantilevered Balconies

from Dieter Hardock

Cantilevered balconies are common in residential structures, yet their traditional design is a slab of continuous concrete passing through the building envelope. This concrete slab balcony creates one of the most significant thermal bridges with excessive heat loss.

As buildings improve with higher performance walls and windows, the amount of heat loss at the balcony slab is increased. Therefore, designers are looking for solutions to thermally separate the interior slab from the exterior balcony slab.


From a structural point of view, balconies have to resist several loadings conditions like permanent loadings (dead load), variable loadings (live loads, wind loads, snow loads) and rare loadings resulting from earthquakes. Seismic considerations could have a relevant influence on the design of buildings depending on the geographic location of the building (seismic hazard), soil characteristic, stiffness and weight of the building, the assemblies and so on. … read more

21. August 2013

Parapet Walls with Thermal Control Layer

from Adam Kimble

If you are familiar with Schock Isokorb® you may associate it with products that limit thermal bridging in the wall portion of the building envelope in such areas as balconies or canopies. These solutions provide a continuous insulation layer in the vertical plane of the wall. As we look at the building envelope in a holistic approach, we can focus on other problematic areas that can be resolved with additional Isokorb® products.

Parapets Function

Parapet walls, much like balconies, are thermal bridges that allow conductive materials to transfer energy through the thermal barrier. The two differ, as balconies are typically added as an aesthetic, giving the appearance of an extended living space within a unit, yet parapet walls are designed as part of the structural integrity of the building.

Parapet walls are designed to resist variable wind pressure differences, protecting mechanical units and other roof assemblies mounted on top of buildings. As an integral part of the building structure, parapets can prove problematic in many forms, such as: lateral failure, membrane failure, water intrusion, and improper water drainage. Therefore, when considering all of these possible setbacks, continuity of thermal insulation may be a secondary thought. The current, traditional practice to remedy such problems is to wrap the parapet with insulation. However, this application could become complicated in areas where the parapet wall is adhered to insulation,  and the insulation is adhered to the roofing membrane.

As Yogi Berra once said, “In theory, there is no difference between theory and practice. In practice, there is.”

Parapet without thermal breaks

View pdf of traditional Parapet without thermal breaks for cast-in-place concrete

… read more

14. March 2013

Window Wall Detail at Balcony / Slab Connection

from Adam Kimble

Every balcony, penetrating the building envelope with scenic window walls, has three main issues to be addressed: thermal bridging, forces at the balcony/slab connection, and water intrusion. The Schöck Isokorb® Type CM is the effective solution for these obstacles, reducing the heat flow from the inside to the outside, while also conserving full structural integrity.

Isokorb CM crosssection

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