External Wall Insulation (Solid Masonry)

SYSTEM OVERVIEW – External Solid Wall

Application Type:
External insulation to solid masonry walls

System Classification:
Breathable External Wall Insulation – Ventilated Rainscreen Build-Up

Primary Function:
Breathable insulation + Secondary rain barrier + Radiant barrier

Installation Orientation:
Horizontal installation across horizontal wall battens or suitable supporting substructure (e.g. metal framing systems or façade support brackets), depending on structural requirements

Primary Substructure Centres:
Maximum 600 mm centres, regardless of type (timber battens or metal support system)

Fixing Method:
Maximum 300 mm centres – for metal substructures, appropriate mechanical fixings must be used (e.g. screws with washers or fixing plates instead of staples)

Overlap System:
Integrated 100 mm built-in flap with double-sided tape

Cavity Configuration:
Unventilated cavity between masonry and insulation
Ventilated and drained cavity between insulation and external finish

Weather Exposure:
Secondary rain barrier – must be covered within 48 hours

External Finish:
Cladding, render board, or approved façade system

The SuperFOIL External Wall System is designed as a breathable insulation solution for solid masonry walls installed behind a ventilated external finish.

It improves thermal performance while allowing moisture to migrate outward through the wall build-up.

This system is typically specified for:

• Solid brick or blockwork walls
• Retrofit façades
• Ventilated rainscreen systems
• Timber-clad external elevations

The product acts as a secondary rain barrier and must always be installed behind a permanent external finish.

Pre-Installation Assessment

Before installation begins:

• Inspect walls for structural damage or dampness
• Confirm pointing and render are in good condition
• Check roof, guttering and drainage systems
• Verify windows are properly sealed
• Preserve all existing ventilation outlets
• Review local building regulation requirements

If services pass through the wall:

• Isolate or protect services where necessary
• Plan penetrations prior to installation

Recommended System Components

The system typically includes:

• SuperFOIL Breathable insulation
• SuperFOIL Breathable Tape, Double-Sided Adhesive Tape
• Treated timber battens or suitable metal substructure systems
• Mechanical fixings suitable for substrate
• Galvanised or stainless steel staples
• External finish (cladding, render board or façade system)

Storage & Handling

• Store products in a clean, dry environment
• Protect from direct sunlight
• Do not store while wet
• Protect exposed insulation from weather

How The External Wall System Works

Step 1 – Primary Support Substructure

The first layer of substructure (timber battens or metal support system) is fixed directly to the wall:

• Fixed at the top, bottom and edges of the wall
• Forms the structural support frame
• Creates an unventilated cavity between the wall and insulation

Horizontal substructure elements are then installed within the frame at maximum 600 mm centres.

Step 2 – Preparing the First Run

Measure the wall and cut insulation to length.

Prepare the integrated 100 mm built-in flap:

• Fold the flap over exposed insulation layers
• Peel backing from integrated double-sided tape
• Press firmly to create a sealed waterproof edge

This prepares the first run of insulation.

Step 3 – Installing SuperFOIL

SuperFOIL must be installed:

• Horizontally
• Breathable membrane facing outward
• Perforated foil facing the wall

Installation sequence:

• Begin at the bottom of the wall
• Each new run installed above the previous run
• Built-in 100 mm flap overlaps the preceding run

Fixing method:

• Staple along battens or metal substructure
• Remove slack before stapling
• Staples at maximum 300 mm centres

For metal substructures, appropriate mechanical fixings must be used (e.g. screws with washers or fixing plates instead of staples).

Seal each run before installing the next:

• Peel backing from integrated tape
• Apply light downward tension
• Press firmly to create sealed joint

Edge & Roll Joint Detailing

If insulation stops at a corner:

• Turn back breathable membrane
• Trim internal insulation layers
• Wrap membrane around the corner
• Staple to adjacent wall

If a roll ends mid-wall:

• Trim insulation layers to centre of last batten or metal substructure element
• Butt new roll to cut edge
• Fold membrane overlap
• Seal joint with SuperFOIL Breathable Tape, Double-Sided Adhesiva Tape

COUNTER BATTENS & VENTILATED CAVITY

Once insulation is secured:

• Install counter battens over insulation
• Create a vertical ventilated cavity
• Bottom of the frame left open to allow drainage and airflow
• Counter battens at maximum 600 mm centres

If vertical cladding is used:

• Additional horizontal battens may be required

The ventilated cavity:

• Allows water runoff
• Enables airflow
• Protects the façade structure

WINDOW & DOOR FRAME DETAIL

Roll insulation over the opening and mark the outer edge of the frame.

Cut insulation carefully to fit snugly around the frame.

Ensure:

• No gaps around frame
• All cuts sealed with Breathable Tape, Double-Sided Adhesive Tape
• Airtight perimeter maintained

PENETRATIONS

At service penetrations:

• Trim insulation carefully
• Avoid excessive openings
• Seal the contact area with Breathable Tape, Double-Sided Adhesive Tape

All penetrations must be properly sealed to maintain system performance.

CORNER DETAILS

For corners greater than 90°:

• Frame each wall individually

For corners 90° or less:

• Install battens or metal substructure elements, adjacent at equal distance from the corner

Insulation must be securely stapled to battens or substructure on both walls.

Counter battens applied after insulation installation.

INSECT MESH / CLOSURES

Perforated closure or insect mesh may be installed:

• At the top and bottom of the cavity
• To prevent pest entry
• While allowing unrestricted ventilation and drainage

AIRSPACE & PERFORMANCE

Correct batten sizing is essential to maintain cavity depth.

The ventilated cavity:

• Enables drainage
• Maintains airflow
• Protects insulation performance

Incorrect cavity configuration may:

• Reduce performance
• Restrict drainage
• Compromise façade durability

SEALING REQUIREMENTS

All cuts, overlaps and penetrations must be sealed using SuperFOIL Breathable Tape.

Double-Sided Adhesive Tape or mastic sealant may be used where necessary.

Proper sealing ensures:

• Weather resistance
• Wind tightness
• Long-term system performance

WEATHER PROTECTION

SuperFOIL Breathable products act as a secondary rain barrier only.

They must be covered with the permanent external finish within 48 hours of installation.

If immediate covering is not possible:

• Use tarpaulins or temporary weather protection

Prolonged exposure is not recommended.

CUTTING METHODS

Recommended cutting methods:

• Utility knife with straight edge
• Electric rotary cutter
• Heavy-duty shears

Compress insulation before cutting to ensure clean, accurate edges.

When trimming insulation layers:

• Peel back membrane
• Trim internal layers
• Avoid damaging membrane

INSTALLATION CHECKLIST

Before completion ensure:

• Wall inspected for suitability
• Product cut accurately
• All overlaps sealed
• Staples ≤ 300 mm centres (or appropriate fixings for metal substructure)
• Counter battens ≤ 600 mm centres
• Ventilated cavity maintained
• External finish installed
• Installation documented