Window insulation with the joint tape

Fits easily into every joint and corner. At any temperature.

Fast installation in any temperature and weather: without foam or residue - for clean, safe and chemical-free window connections.

Comparison of window insulation
Picture: RS product

Typical challenges in window insulation

Different joint widths

Often are joints not exactly the same width: Instead of 5 mm, it is sometimes 3 mm or 7 mm.
Insulation values sheep's wool

Temperature dependence:
Additional work and risk due to heat, cold and humidity.
UV resistance

UV resistance and weather resistance must be guaranteed in the long term.
Sensitive corner formation

Sensitive corner formation:
Compribands quickly reach their limits here, foam overflows.

Your advantages with the natural ISOLENA joint tape

Installation:

  • Fast, clean installation - No swelling, no unwanted sticking, no subsequent cleaning.
  • Total time expenditure 1:1 - identical to tapes and foams, but without their disadvantages.
  • At any temperature and humidity - without airing, without curing, immediately loadable.
  • Harmless to health - No additives, no vapours, no protective clothing required.
  • Simple window replacement - No cutting out, no dirt, no double material costs.
Durability:
  • Permanently elastic - withstands vibration and movement of the window frame.
  • Permanently insulating - Dimensionally stable and UV-resistant even at extreme temperatures.
  • Physically safe - Perfect moisture equalisation: no condensation, no mould.
Economical and sustainable:
  • Clean building site - No waste, no disposal effort.
  • Tested performance - Sound insulation up to 62 dB according to EN ISO 10140.
  • Competitive advantage of sustainability - Ideal for ecological construction methods, LEED / BREEAM projects.
Show product details
Installation of window insulation Picture: RS product

Structure of window insulation with sheep's wool

Window insulation with a system

Airtight, windproof, driving rain-proof.

Simple structure:

  1. ISOLENA window filler (λ = 0.033 W/mK | RST, W = 58 dB)
  2. Joint sealing tape (BG 1), e.g. pro clima CONTEGA FIDEN EXO
  3. Airtight bondinge.g. pro clima CONTEGA SOLIDO IQ-X
    (also mullion to transom)
  4. with All-round adhesive tape e.g. pro clima TESCON VANA

Everything compactly to hand with the Flyer on window insulation.

Simple installation:

The joint tape is simply pressed into the joint. The Installation time is 1:1 to assembly foam and tapes, but cleaner, more controlled and harmless to health.

Watch installation on YouTube
Window installation video instructions

Correct installation

How much joint tape is needed?

Fill the joints completely for optimum sealing.
Our recommendations for installation:

  • To Standard requirements for window insulation, we recommend with a joint depth > 50 mm and joint height < 10 mm apply the joint tape in two layers so that all areas are securely filled.
  • To achieve a joint sound reduction index RSW (C;Ctr) of ≥ 62(-2;-5) dB, the following applies: For a joint 10 mm high, 100 mm deep and 1000 mm long, you need a length-related mass of approx. 130 g/m according to the IFT-Rosenheim test. This corresponds to approx. 4 metres of joint tape applied to the joint.
IFT Rosenheim test seal

Note on summarisation:
The ISOLENA joint tape can be easily compacted to approx. 100 kg/m³. Higher compaction leads to unnecessarily high material consumption. The above quantity has been tested and confirmed by IFT Rosenheim in accordance with EN ISO 10140 / 717-1

Moisture behaviour insulation study
Put an end to mould, structural damage and discomfort:

Sheep's wool regulates moisture better than conventional insulation materials

In practice, it has been shown that ISOLENA sheep's wool insulation remains stable even when exposed to moisture - without condensation or mould. Series of measurements clearly show that the moisture values are far below critical limit curves.

While polyurethane - whether as swelling tape or foam - hardly absorbs any moisture and can therefore promote waterlogging and mould growth, sheep's wool has a naturally active balancing effect.

  • With a μ-value of 1 is ISOLENA sheep's wool Completely open to diffusion - Moisture can escape unhindered. Swelling tapes are between μ = 3 - 10, PU foam at μ = 10 - 50 and multifunctional swelling tapes at μ > 20 - 200, which is completely tight.
  • The MBV value of 3 g/m²-%rF also demonstrates excellent moisture buffering: sheep's wool absorbs excess moisture from the air and releases it again when required. Here too, sheep's wool leaves swelling tapes and PU foam far behind with values of ≤ 0.1.

This keeps the structure dry, the building fabric protected and the indoor climate constant - even in changing conditions.

Figures on the left: The measured moisture behaviour over a period of one year in the "point cloud" shows that sheep's wool insulation is far below the recommended limit curves. (Source: CORNET final report "Building components with insulation material made from renewable raw materials: Focus on (Hygro-)Thermics" © Fraunhofer Institute for Building Physics/Wood Research Austria 2023)

Tried and tested on construction sites

Recommended by professionals from the field

» Working with ISOLENA joint tape is a pleasure for several reasons. Processing is child's play and completely harmless to health. The technical values, such as sound values, thermal conductivity or fire behaviour are top and there is no waste. «

Roland Dorn, Dorn Fenster und Türen GmbH

Roland Dorn from Dorn Fenster und Türen GmbH

Total cost calculation
Fairly calculated

The real costs on the construction site

If you only compare the price of materials, you overlook the true costs. What really matters is what is actually involved in installation – from labour time to disposal.

  • Material: The joint tape has the same insulating performance as foams or swelling tapes.
  • Working time: Same amount of time as with PU foam, as many work steps such as foam cutting and cleaning are no longer necessary and work can continue immediately.
  • Cleaning: No gun cleaners, gloves or covers required.
  • Reworking: Residue-free removal - no cutting out and no duplication of material.
  • Disposal: No hazardous waste, no empty containers.

The result is a solution that saves time, effort and costs - permanently tight and cleanly finished.

Sell with added value

Convince with natural alternatives

Those who rely on sustainable materials deliver more than just handcrafted quality - they demonstrate foresight. Position yourself as a strong partner for ecological construction methods with architects and building owners..

The ISOLENA waterstop is not only technically convincing, but also a strong sales argument:

  • Credible sustainability - 100 % sheep's wool, CO₂-binding, natureplus® tested, with EPD, ideal for ecological construction projects.
  • Perfect addition to timber construction - Natural insulation perfectly complements wood, clay and other ecological building materials.
  • Health for the residents - Clean, chemical-free solution without vapours or additives. Good for installation, good for living.
  • A head start in tenders - Be prepared for the increasing demand for sustainable construction methods and ready for maximum sustainability standards in accordance with the EU taxonomy.

In this way, you offer building owners and planners a solution that is technically convincing and creates value.

Aluminium/wood window with ISOLENA joint tape. Installation: Dorn GmbH, Image: Andreas Buchberger

Naturally tight

Sheep's wool ensures perfect window connections

STRABAG residential building 'Taborama'
STRABAG residential project Taborama, AT
STRABAG residential project Taborama, AT

The Taborama residential building has it all in the truest sense of the word: it's the first high-rise building in Austria to use natural sheep's wool as ecological interior insulation. 29,000 m² of ISOLENA insulation provides insulation, good air quality and a favourable CO2 balance.

Window insulation House Kittenberger
House Kittenberger, AT
House Kittenberger, AT

A green roof, trees for natural cooling and a garden that is a real gem: when building his timber house, Lower Austrian gardening professional Reinhard Kittenberger placed great value on nature. For the window connections, the Dorn company therefore consistently used chemical-free ISOLENA window filler.

Large household with 9 residential units
Apartment block, CH
Apartment block, CH

As part of the refurbishment of an old residential building into a large communal house with nine residential units, natural materials were specifically used for an ecological construction method. Around 350 m² ISOLENA sheep's wool were used in the roof and interior walls to promote a healthy indoor climate.

Green Cube Project
STRABAG Green Cube Project, AT
STRABAG Green Cube Project, AT

The Green Cube, a seven-storey building comprising around 319 serviced studios, is being built in Vienna's trendy Nordbahn district. The interior walls will contain 7,080 square metres of Optimal sheep's wool insulation integrated, which provides excellent thermal insulation and helps to minimise DGNB Gold pre-certification to obtain.

Window insulation Wildburger House
House Wildburger, AT
House Wildburger, AT

This ecologically sustainable passive house in solid timber construction is located in the Lower Austrian market town of Türnitz. At the Installation of modern wood-aluminium windows with triple glazing, the Dorn company relied on the ISOLENA window filler.

Reference Mobile Learning Workshop
Mobile learning workshop, DE
Mobile learning workshop, DE

The "Green Little Circle" project illustrates the circular economy in the construction industry through a mobile learning workshop developed by international students. ISOLENA sheep's wool insulation was integrated into the roof, floor, exterior walls and windows.

Acoustically optimised meeting room
Lehner Wool Centre, AT
Lehner Wool Centre, AT

How could it be otherwise: sheep's wool products are of course particularly popular in our own construction projects. From insulation to carpet and acoustic felt, our Lehner wool centre has it all.

View references for window insulation
naturally well advised:

Personal, honest, solution-orientated

Whether you are an architect, fabricator or retailer - we support you with expertise, tested solutions and honest advice. You will receive answers, inspiration and suitable products made from sheep's wool. Sustainable. Effective. From a single source.

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