insolation Xpander


Create extra insulation space with this adaptable expansion system for roofs, walls and floors

Insulation Xpander is an innovative product which provides greater flexibility in the thermal refurbishment of existing buildings. The system can also be utilised in new buildings. Insulation Xpander has been developed,patented and engineered in Germany, its creates additionalinsulation space for roofs, walls and floors in an effective, economical and safe manner. The system can be applied either internally or externally.

The principle of the system is to simply install an engineered beam onto the existing construction or to combine this beam with a specifically designed pocket, which in turn, increases the volume of insulation which can be installed. Any element of the building fabric can be insulated over a broad range of depths.

Insulation Xpander is lightweight and easy to handle on site, whether on walls or in confined attic spaces. A major limitation of retrofitting existing buildings can be the additional costs incurred to level up uneven walls or roofs prior to insulating.

Insulation Xpander allows installers to rapidly level off walls or roofs safely and cost effectively

Thermal refurbishment of attics and walls

A major limitation in the thermal refurbishment of existing buildings is the limited depth of existing rafters or joists. This often leads to the requirement to either replace existing timbers which may still be in good condition or the requirement for additional solid timber which adds significant weight to the roof. The Insulation Xpander system allows contractors to more efficiently align rafters or joists and at the same time significantly increase insulation thicknesses in a safe and cost effective manner. As the system is very lightweight it does not add significant weight to the roof structure.

The system also provides an efficient solution for the thermal refurbishment of attic spaces. In order to meet the latest requirements of the building regulations or to meet Passivhaus levels of energy performance more the 300mm of fibre insulation is often required. Homeowners often use attic spaces for storage which can lead to the compression of insulation which in turn, significantly reduces thermal performance. Applying high levels of insulation in attics also increases the difficulty of moving within the attic space.

Attic spaces can be safely and effectively insulated with the SE Expander fixed directly to the joist or with a combination of the SE Expander combined with the DP Fibre insulation strip as shown on Figure 6.

Figure 1: Insulation Xpander Universal Expander (UE) aligns and increases rafter depth to accommodate

more insulation from the outside of buildings

Figure 2:  Insulation Xpander Rafter Expander (SE) aligns and increases rafter depth to accommodate more insulation from the inside of existing buildings

Figure 3: A combination of the SMART SIX Universal Expander (UE) and the FT wall

pocket allows uneven external walls to be more effectively levelled and insulated

Figure 4: Increasing insulation depths on concrete ground floors are simplified with the thermally

broken DP fibre insulation strips in combination with the SE expander


  • Ideal for retrofit and new build
  • Slim, lightweight engineered solutions
  • Easy to handle
  • Increase rafters or joists in one easy step
  • Efficient alignment of uneven walls or


  • Time saving: One-man installation


  • The system also assists in significantly

reducing repeating thermal bridges. This

leads to a 15% improvement on U values

compared to conventional solid timber

studs or rafters

  • Ensures insulation performs to its


  • Provides a stable platform for safe access
  • and storage in the loft
  • The mechanical strength of the rafter

expander has been 3rd party tested and

approved in Germany

  • Patented technology, engineered and

developed in Germany

Insulation Xpander System Elements

FT: Facade pocket used to align

uneven walls (See Figures 3)

UE: Universal Expander can be used to align walls in combination with the FT

pocket. It can also be applied externally

to existing rafters (see figures 1,3)

SE: Rafter Expander SE can be applied

on the inside of rafters, in attics to

increase joist depths or on solid floors

in conjunction with the DP Insulation

strip (see figures 2,4 &5)

DP insulation strip: Used in attics or

on top of solid ground floors.

Thermally broken strip into which the

SE expander is inserted (see figures 4