What to keep in mind
The challenges of activity roofs

Activity Roofs can help you make the most of the scarce, underutilised space in our crowded cities, now and in the future.
The possibilities are endless.
However, there are possible pitfalls involved during both the construction and operational phase. It’s best to keep the following in mind at all times.

You don’t want to use the wrong insulation materials. Here’s why

Activity Roofs are popping up everywhere, becoming more than a trend in modern society. Although the benefits of these roofs are indisputable, there are risks involved with the construction.

Using the wrong insulation materials can have a major impact on your project. By adding additional layers of activity roof to a basic flat roof build-up, certain factors can increase the risk of damage. High repair costs, downtime and stress are just some of the consequences.

Challenges of an Activity Roof:

  • Increased load from the use, construction and dead weight of roof layers, which may lead to deformation of the insulation material and damage to the roof surface
  • Change in interstitial condensation conditions in the roof build-up which can lead to moisture build-up through time
  • Interstitial condensation or leakages that result in reduced thermal performance due to moisture
  • Possible leakages difficult to locate and repair
  • Root penetration in case of vegetation on roofs may lead to leaks and reduced thermal performance
  • Frequent and intensive use with static and dynamic forces, results in a higher chance of waterproofing damage
  • A future change in the utilisation of a roof may cause problems if an inappropriate build-up is installed
  • Combustibility of materials may lead to a fire hazard

A roof build-up with the appropriate building materials and a perfect installation are key to mitigating these risks. That’s where FOAMGLAS® Compact Roof comes in.

FOAMGLAS® helps you mitigate the risks

FOAMGLAS® Compact Roof offers you a fully-bonded and closed joints build-up.  It's an easy to construct but technically sound roof system reducing all of the risks associated with activity roofs. 


Here is how:

Higher load on activity and green roofs

FOAMGLAS® thermal insulation in a compact roof build-up can withstand different high compressive load needs and bear all loads permanently, safely and without affecting its insulation properties.

The closed glass cell structure also means it is resistant to any kind of deformation. This ensures that the waterproofing and all layers of the build-up can stand the test of time. 

Change in interstitial condensation conditions

FOAMGLAS® thermal insulation consists of closed glass cells stacked on top of each other, creating a hermetically sealed volume that is watertight and vapour proof, remaining dry under all conditions if properly installed as described.

in this case the thermal resistance is guaranteed as well as no water or vapour issues can occur throughout the lifetime of the building.

Reduced thermal protection over time

FOAMGLAS® thermal insulation has proven its durability and long-term thermal protection over time.

After decades of service the insulation maintains its properties consistently throughout time. An impressive feature that gives you complete peace of mind.

Root ingrowth

FOAMGLAS® thermal insulation remains 100% dry in all conditions throughout the lifetime of the building if properly installed as described. The cellular glass structure prevents roots from penetrating the material in search of water.

FOAMGLAS® guarantees zero root ingrowth.

Waterproofing damage when applying additional layers

With its closed cell structure, FOAMGLAS® thermal insulation can bear high loads with zero risk of deformation.

Applied in a compact roof build-up, a rigid and stable roof volume is created, minimising any risk of damage when installing additional layers.

Inability to locate and repair waterproofing defects

The FOAMGLAS® Compact Roof system is vapour tight and non-absorbent. Any waterproofing failure remains local and is easy to detect and cheap to repair thanks to its small compartmented grid build up through the fully bonded and closed joints system.

Future changes in roof use

FOAMGLAS® Compact Roof insulation is vapour tight, non-absorbent and able to handle extreme loads. Practically any Activity Roof can be built upon the core compact roof build-up and the use of the roof can easily be changed in the future.

Keep in mind that when it’stime to repurpose a roof, any damage due to an improper build-up can be costly and difficult to resolve. Avoid the stress and downtime with the right build-up and proper insulation.

Curious about the different types of Activity Roofs? Here’s what you need to know.

Want to learn more about activity roofs?

Discover all insights of Activity roofs

In the document "Safe, long-term solutions for activity roofs", we address the many issues that designers face and that can lead to serious consequences if not anticipated.
Then we describe new solutions adapted to the uses of active roofs (photovoltaic, vegetated, accessible to pedestrians/vehicles).

Our document will provide you with the keys to designing and making a success of these living spaces, with total architectural freedom.