To better understand exactly what Airtightness is, think of a person running. Just as runners play it smart by wearing breathable clothes when running, you can play it smart with protecting your home with the ISOVER Vario System. Both marathon runners AND buildings need breathable, high-performance clothing that is specifically designed to regulate moisture when functioning. 

What is the ISOVER Vario System?

The ISOVER Vario System is an intelligent airtightness and moisture control system.

This airtightness and moisture control system comprises of a range of intelligent membranes, tapes and sealant. It adapts to the climate and protects your building against moisture and dampness, inside and out. Airtightness also protects the building fabric against damage, helping to maintain its appearance and extending the building’s life.

Why do we need Airtightness?

A building is subject to several weather constraints toughly predictable. The challenge is to provide an effective and sustainable structure adapted to the surrounding environment, ensuring comfort and perennial use for its occupants. One of the keys to success is the creation of a perfect building envelope, using synergy of a performing insulation solution and a complete airtightness.
Airtightness protects the building fabric against damage, helping to maintain its appearance and extending the building’s life. Only when the construction is airtight can warm air be retained within the building and cold air kept outside. Preventing unpleasant draughts means greater living comfort and increased energy efficiency, which in turn leads to lower heating costs.
ISOVER Airtightness

Another reason airtightness is important for your home is to protect against moisture and dampness. Within buildings, people, animals and plants continuously release moisture. During the colder months of the year, when the interior temperature of the building is higher than that outside, this moisture is carried outside with the warm air through joints and cracks. This moisture is then condensed within the building structure. This uncontrolled penetration of moisture is equally damaging for both solid and lightweight constructions. The only way to avoid this from occurring is a by making the building shell airtight.

The Benefits 

The ISOVER Vario System comprises of two intelligent airtightness membranes – accessory airtightness tapes and a sealant. These intelligent airtightness membranes help prevent your home from airtightness and moisture. Other benefits of using the ISOVER Vario System are:

  • Excellent levels of airtightness within the building
  • Protection against moisture by facilitating the drying of the building structure
  • Variable Sd value and can diffuse 25 more times more moisture in summer than the structure absorbs in winter
  • Improve your building energy rating (BER) and reduce environmental footprint of building
  • Help save money
  • Increase home comfort
  • One of the safest systems available
  • Meets and exceeds industry standards

Installing The Vario System 

ISOVER Vario System

To avoid unpleasant draughts and dampness in your home, we recommend installing the ISOVER Vario System.
The Vario System will provide you with high performing airtightness and moisture control. Ideal complement to ISOVER insulation materials, the Vario® system includes adhesive tapes, joints, sealants and primer, to make a perfect airtight installation.
Years of practical use has proven the value of the Vario® products, which are now used worldwide to protect countless buildings against air leakage and damp. With its complete products range, the system can adapt according to your applications, your substrates and your climate to perfectly match your requirements.
For more information on the products in the Vario range, please click on any of the product images below. For information on the Vario Xtra range and Vario XtraSafe membrane, which will help you achieve the highest levels of airtightness whilst saving you time, you can download the Vario Xtra Brochure here.


ISOVER is awarded the NSAI Certification of Standard. The certification is designed specifically for new building materials, products and processes that do not yet have a long history of use and for which published national standards do not yet exist. NSAI Agrément assesses, specifies testing, and where appropriate, issues Agrément certificates for such products. NSAI Agrément is responsible for Agrément assessment and certification. The process of Agrément certification applies to those products and processes that are not already regulated by existing building standards, either because they are innovative or because they deviate from established norms. For more details on this certification, please click here.