Rapid Performance Solutions with our Roof Systems App

Build Roof Systems In Seconds

Our Roof System app allows rapid design and specification of complete wall systems, including thermal, condensation, lifecycle assessments and other advanced design features, to generate roof system National Construction Code 2019 – Performance Solutions.

1. Templates

Select from lightweight, heavyweight or supplier templates or build your own!

2. Framing

Design with a range of real wall products, including ventilation and thermal bridging strategies.

3. Roof Products

Specify thousands of roof products from trusted suppliers.

What is a Total System R-Value Calculation?

A Total R-value calculation for wall systems involves both the thermal performance of wall material and thermal bridges such as timber or steel framing. The Speckel Wall App takes the complexity out of this calculation to provide you with a simple and flexible R-value app that generates results in a matter of seconds.

How can I achieve a better wall System R-value?

Both excessive cavity ventilation and highly conductive framing can reduce the Total  R-value of your wall, resulting in poor thermal performance for your building. The new National Construction Code 2019 requires that such impacts are considered.

Calculated in accordance with AS/NZS 4859.2 and NZ 4214, the latest Standards for wall performance assessment


Specify from thousands of wall products from trusted suppliers

Understand how your design stacks up against compliance in the National Construction Code


Performance Solution reporting to communicate with you design team and certifers

What is a thermal bridge?

External walls are often structurally supported by timber or steel partitions. Such partitions typically run through the thermal control layer and represent (the combination of frame plates and noggins) between 10 – 15% of the overall area of a standard full-height wall. These are known as construction thermal bridges.

As a result of this thermal bridging effect, they increase the overall thermal transmittance of the wall and need to be considered. Steel wall frames, with high thermal conductivity, are particularly poor performing and may need to consider non-combustible thermal breaks to ensure a continuity of the thermal control layer.

What are the impacts of thermal bridges?

The rate of heat transfer depends on the thermal conductivity of the material and the temperature difference on either side of the thermal bridge. When a temperature difference is present, heat flow will follow the path of least resistance through the material with the highest thermal conductivity and lowest thermal resistance, creating the thermal bridge.

As a result, where warm, moist internal air comes into contact with the potentially cold, surface, condensation can result in mould growth and durability issues. Despite insulation requirements specified by various national regulations, a building’s envelope remains a weak spot in the construction industry and is only regulated in a small number of cold climate construction markets. Thermal losses are likely greater in practice than that anticipated during the design stage and are potentially one of the main sources of unquantified heat losses in better performing building envelopes.

Speckel - footer logo