ITI BC-RP-IM-V5 User manual

BC-RP-IM-V5
www.ititimspec.nz
Bevelback Cavity System
Radiata Pine
Installation Manual
V5 - 2021

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**IMPORTANT**
This Installation Manual (IM) is specific to
RADIATA PINE (RP) and BEVEL BACK cavity system (BC) profile only.
Specific drawings in this Installation Manual can be found at the back.
There are 9 CertClad Installation Manuals in the following profiles and timber species.
Profiles are Bevel Back, Vertical Shiplap and Rusticated. The timber species are Accoya,
Western Red Cedar and Radiata Pine.
CertClad is a certified installation system and supplied by ITI Timspec.
You can find these documents on our website www.ititimspec.nz/downloads. If you have any
questions, please feel free to contact us. Auckland office [phone] or
[e-mail]

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CONTENTS
SCOPE .............................................................................................................................................. 4
1.1 INTENDED USE ................................................................................................................................. 5
1.2 VALIDITY........................................................................................................................................ 5
1.3 PERFORMANCE ................................................................................................................................. 5
1.4 LIFESPAN ........................................................................................................................................ 5
HEALTH AND SAFETY ........................................................................................................................ 6
2.1 CUTTING OF TIMBER.......................................................................................................................... 6
2.2 COATING AND PRIMING ...................................................................................................................... 6
SITE PREPARATION............................................................................................................................ 7
3.1 STRUCTURE AND FRAMING .................................................................................................................. 7
3.2 BUILDING UNDERLAY ......................................................................................................................... 7
PRE-INSTALLATION........................................................................................................................... 8
4.1 ON-SITE STORAGE AND HANDLING ....................................................................................................... 8
4.2 DOCKING OUT DEFECTS..................................................................................................................... 8
4.3 PRIMING AND SEALING ....................................................................................................................... 8
MATERIALS - CAVITY SYSTEM COMPONENTS ..................................................................................... 9
5.1 CAVITY SYSTEM COMPONENTS ........................................................................................................... 9
5.2 TIMBER SPECIES:RADIATA PINE ............................................................................................................ 9
5.3 RADIATA PINE BEVELBACK WEATHERBOARDS............................................................................................ 9
5.4 FLASHINGS.................................................................................................................................... 10
5.5 NAILS .......................................................................................................................................... 10
5.6 CAVITY BATTENS ............................................................................................................................ 10
MATERIALS - ACCOMPANYING ELEMENTS ........................................................................................ 11
6.1 ACCOMPANYING ELEMENTS ............................................................................................................... 11
6.2 TIMBER FRAMING............................................................................................................................ 11
6.3 BUILDING UNDERLAY ....................................................................................................................... 11
6.4 FLASHING TAPE.............................................................................................................................. 11
6.5 SEALANTS AND ADHESIVES ................................................................................................................ 11
6.6 PEF ROD...................................................................................................................................... 12
6.7 METER BOX ................................................................................................................................... 12
6.8 INTERNAL LINING............................................................................................................................ 12
INSTALLING CAVITY BATTENS.......................................................................................................... 13
7.1 CAVITY CONSTRUCTION ................................................................................................................... 13
FIXING DETAILS FOR WEATHERBOARD.............................................................................................. 14
8.1 INSTALLATION ............................................................................................................................... 14

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INTER-STOREY CAVITY JUNCTION ................................................................................................... 15
9.1 DEFINITION................................................................................................................................ 15
WITHIN-BOARD JOINS (SCARF JOINT) ............................................................................................... 16
10.1 LIMITATIONS ................................................................................................................................. 16
10.2 METHOD ...................................................................................................................................... 16
SITE CLEAN-UP ............................................................................................................................... 17
11.1 AT COMPLETION ........................................................................................................................ 17
ON-GOING MAINTENANCE .............................................................................................................. 18
12.1 MAINTENANCE INTERVAL .................................................................................................................. 18
12.2 MAINTENANCE REQUIREMENTS ........................................................................................................... 18
CONSTRUCTION DETAILS ................................................................................................................ 19
CONTACT....................................................................................................................................... 41

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TABLE OF FIGURES
FIGURE 13. 1 BC 106 PAINT FINISH WITH STANDARD CAVITY FIX ................................................................................19
FIGURE 13. 2 BC 108 STAIN FINISH WITH STANDARD CAVITY FIX ................................................................................20
FIGURE 13. 3 BC 201 WINDOW HEAD –ALUMINIUM JOINERY .......................................................................................21
FIGURE 13. 4 BC 202 WINDOW JAMB –ALUMINIUM JOINERY ........................................................................................22
FIGURE 13. 5 BC 203 WINDOW SILL –ALUMINIUM JOINERY ..........................................................................................23
FIGURE 13. 6 BC 301 INTERNAL CORNER NOTCHED & SCRIBED ...................................................................................24
FIGURE 13. 7 BC 302 INTERNAL CORNER MOULDING ..................................................................................................25
FIGURE 13. 6 BC 401 INTER-STOREY CAVITY JUNCTION..............................................................................................26
FIGURE 13. 7 BC 402 WITHIN BOARD JOINS (SCARF JOINT) ..........................................................................................27
FIGURE 13. 8 BC 403 BOXED CORNER.........................................................................................................................28
FIGURE 13. 9 BC 404 CORNER SOAKER .......................................................................................................................29
FIGURE 13. 10 BC 501 BASE, TIMBER FLOOR ..............................................................................................................30
FIGURE 13. 11 BC 502 BASE, CONCRETE SLAB ON GROUND ........................................................................................31
FIGURE 13. 12 BC 503 BASE, JUNCTION WITH BOTTOM OF CLADDING/ CLADDING FINISH ABOVE DECK .......................32
FIGURE 13. 13 BC 601 ROOF/ WALL TOP PLATE –FLAT SOFFIT....................................................................................33
FIGURE 13. 14 BC 602 ROOF/ WALL TOP PLATE –NO SOFFIT ......................................................................................34
FIGURE 13. 15 BC 701 PARAPET/ CAPPING –EXPANSION JOINT ...................................................................................35
FIGURE 13. 16 BC 702 BALUSTRADE INTERSECTION WITH THE WALL ...........................................................................36
FIGURE 13. 17 BC 801 METER BOX HEAD....................................................................................................................37
FIGURE 13. 18 BC 802 METER BOX JAMB.....................................................................................................................38
FIGURE 13. 19 BC 803 METER BOX SILL.......................................................................................................................39
FIGURE 13. 20 BC 851 PIPE PENETRATION DETAIL.......................................................................................................40

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SCOPE
1.1 INTENDED USE
This Bevelback Weatherboard Cavity System has been designed for use as cladding for residential and
light commercial buildings. It is suitable for buildings with a ‘Risk Score’ of 0 - 20 Calculated in accordance
with New Zealand Building Code (NZBC) Clause E2/AS1 Table 1 and Wind Zones up to and including extra
high.
1.2 VALIDITY
Cerclad is only valid when all products in the weatherboard system are as listed in the product certificate
and in this manual. This is to ensure that all products meet the requirements of Certclad and are installed
in the correct manner.
1.3 PERFORMANCE
When installed and maintained as specified in this manual and the work is done by a qualified tradesman
using accepted trade practices, it will meet the applicable sections of the following requirements of the
NZBC (New Zealand Building Code):
•B1 Structure
•B2 Durability
•E2 External Moisture
•F2 Hazardous Building Materials
1.4 LIFESPAN
1.4.1 SERVICEABLE LIFE
ITI Timspec Radiata Pine is warranted for between 15 –40 years depending on coating selected.
This serviceable life is subject to the coating and maintenance requirements below. More importantly, some
timber boards may require replacement over the lifetime of the cladding as part of normal maintenance.
1.4.2 COATING REQUIREMENTS
For H3.1 or H3.2 treated Radiata Pine with a dressed surface, all faces (hidden and exposed) must be
paint finished, consisting of two coats of an approved primer and all exposed faces coated with a further
two coats of a suitable topcoat, refer to chapter 4.3 (Priming and Sealing, page 7) and 6.2.4 (Coating, page
8) for more detail.
1.4.3 MAINTENANCE REQUIREMENTS
When a coating is applied, periodic maintenance and recoating is required to ensure the integrity of the
coating is sustained. This will generally mean applying another exterior coat every 10 years dependent on
the coating used and building location after washing and maintenance.
Please refer to the On-Going Maintenance section 12 (page 18) for more information about the required
maintenance.

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HEALTH AND SAFETY
2.1 CUTTING OF TIMBER
Cutting of timber is to be done in a well-ventilated area and a suitable dust mask, eye protection, and ear
protection must be worn.
2.2 COATING AND PRIMING
Coating and priming are to be done in a well-ventilated area, refer to the coating/primer supplier for all
matters relating to health and safety. All relevant sections of AS/NZS 2311:2009 (Guide to the painting of
buildings) and all of the coating manufacturer’s requirements must be adhered to.
Contact Information is technica[email protected]; [phone] or www.ititimspec.nz

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SITE PREPARATION
3.1 STRUCTURE AND FRAMING
3.1.1 NEW ZEALAND STANDARD 3604
Generally, the timber framing must comply with NZS 3604 (2011) (Timber-framed buildings), however,
where specific engineering design is required the framing shall be at least of equivalent stiffness as the
framing provisions of NZS 3604 (2011).
3.1.2 LAYOUT
Studs must be at spaced at a maximum of 600mm between centres. Dwangs (nogging) must be spaced at
maximum 800mm between centres. Studs and Dwangs must form a flush plane for cavity battens and
weatherboards to be fixed to.
Additional framing may be required at soffits, corners, and penetrations such as window and door openings
to support the installation of battens and flashings.
3.1.3 MOISTURE CONTENT
The optimum moisture content of the weatherboards is between 16 - 18%. The moisture content must not
exceed 20% at the time of fixing as problems may occur with the coating adhesion.
3.2 BUILDING UNDERLAY
3.2.1 MATERIAL
Building underlay and Rigid wall underlays must comply with properties stipulated in NZBC Clause E2/AS1
Table 23 (Properties of roof underlays and building underlays) or equivalent proof of compliance to NZBC.
3.2.2 INSTALLATION
Building underlay to be installed in accordance with underlay manufacturer’s specification, and in
accordance with conditions set out in NZBC Clause E2/AS1. 9.1.7.2.

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PRE-INSTALLATION
4.1 ON-SITE STORAGE AND HANDLING
Care must be taken to ensure that timber and accessories are kept clean and dry, and are not damaged
whilst in storage awaiting application.
Extra care is to be taken while handling timber to ensure that it is not damaged.
Timber is to be stacked on flat level bearers/dunnage that is a maximum of 900mm apart and at least
100mm off the ground. Timber should either be stored inside an enclosed building or covered with an
additional waterproof layer and protected from the elements when stored outside
IMPORTANT Radiata Pine weatherboards should not be installed if their moisture content is above
20%.
4.2 DOCKING OUT DEFECTS
Before coating or installing boards, check for any defects that may require docking out.
IMPORTANT All docked ends, any exposed or bare timber of painted weatherboards will require end
sealing with a minimum of two coats of primer.
4.3 PRIMING AND SEALING
Apply the first coat of primer to all sides and edges of the weatherboard prior to installation. It is critical that
Radiata Pine is at the correct moisture content prior to priming. Remember that all docked ends will require
priming as noted above. Follow the coating manufacturer’s directions and ensure further coats are applied
as required. All relevant sections of standard AS/NZS 2311 (Guide to the painting of buildings) must be
adhered to.

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MATERIALS - CAVITY SYSTEM COMPONENTS
5.1 CAVITY SYSTEM COMPONENTS
All cavity system components must be supplied by, or approved by ITI Timspec. This is to ensure that all
items are up to a suitable standard and to ensure the compatibility and suitability of all items. Any
alternative or competitor supplied product will invalidate the Certclad Warranty.
5.2 TIMBER SPECIES: RADIATA PINE
5.2.1 MATERIAL
New Zealand grown Radiata Pine (Pinus Radiata) which has been preservative treated to a minimum H3.1
(ACQ, CCA, etc.) level.
5.2.2 DURABILITY
ITI Timspec Radiata Pine is warranted for between 15 –40 years depending on coating selected.
The above Warranty assumes regular maintenance. Please refer to the On –Going Maintenance Section
12 for more information.
Please note, some timber boards may require replacement over the lifetime of the cladding as part of
normal maintenance.
5.2.3 COATING
Dark colours attract more heat which will exacerbate any timber movement and/or resin bleed. Therefore
only coatings which have an LRV (light reflectance value) of 45% or higher can be used. Any coating that
has an LRV less than 45% will void the warranty.
5.2.4 IMPORTANT NOTES
Timber treated with a copper-based treatment (ACQ, CCA, etc.) should not be in contact with metal wall
claddings as this may lead to corrosion. Separation is required in the form of an approved DPC.
Material selection to be in accordance with NZBC Clause E2/AS1 Table 21 compatibility of materials in
contact and Table 22.
5.3 RADIATA PINE BEVELBACK WEATHERBOARDS
Radiata Pine can be machined into a variety of profiles, including the range of Bevelback weatherboards as
listed on our Website.
5.3.1 COATING DRESSED AND/OR TREATED WEATHERBOARDS
H3.1 or H3.2 treated painted finish Radiata Pine must have a dressed surface and must be coated with two
coats of primer and two further coats of a suitable alkyd or 100 percent acrylic paint. All relevant sections of
standard AS/NZS 2311 (Guide to the painting of buildings) should be adhered to.
All cut ends must be coated with a minimum of one coat of primer before installation. Immediately after
fixing the weatherboards, all nail holes should be spot-primed and filled, and sanded smooth prior to
painting.

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As soon as possible after fixing the weatherboards they should be over-coated with a minimum of two coats
of suitable exterior grade premium paint. Follow the paint manufacturer’s directions specification.
If the weatherboard has been exposed to the elements for an extended period of time (generally 4 weeks)
or if there is evidence of the primer “chalking”, then re-priming will be necessary. This involves sanding the
primer back to a sound surface and re-priming using a premium oil based primer such as Resene True-
Prime or Dulux Ultra-Prime.
5.4 FLASHINGS
5.4.1 MATERIAL
Flashings can be either: Galvanised Steel, powder coated Aluminium, Stainless Steel (304), or uPVC.
All flashings to comply with NZBC Clause E2/AS1. 4.0 and Table. 7.
If using galvanized steel flashings these must not be use indirect contact with CCA treated weatherboards
in a sea spray zone or corrosion zone D.
IMPORTANT Weatherboard fixings are not to penetrate flashings as this may provide a path for water
to track through.
5.5 NAILS
5.5.1 MATERIAL
Nails shall be either Stainless Steel (304) or in corrosion zones, Stainless Steel (316).
5.6 CAVITY BATTENS
5.6.1 MATERIAL
Minimum H3.1 treated Radiata Pine or Polypropylene (Cavibat).
5.6.2 DIMENSIONS
Battens are 45 x 18 mm.
Cavibat battens have been appraised by BRANZ as a non-structural batten for wall cladding systems.
Refer to E2/AS1 –Section 9.1.8.4
Refer to BRANZ Appraisal No. 524 [2007] for information about Cavibat, including its limitations and
specifications.

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MATERIALS - ACCOMPANYING
ELEMENTS
6.1 ACCOMPANYING ELEMENTS
All items that precede the installation of the weatherboard system (building underlay, roofing underlay,
flashing tape, etc.) and all consumables and items successive to the weatherboard system (PEF backing
rods, flexible sealants, etc.) will not be supplied by ITI Timspec as these are outside the scope of this
specification. These items still require careful evaluation to determine their suitability and still play a critical
role as part of the cladding system.
IMPORTANT It is the builder’s responsibility to ensure that all these accompanying items meet the
requirements and properties stated and more importantly are compatible with adjacent materials and
are fit for the intended purpose, and comply with the relevant clauses of the NZBC.
6.2 TIMBER FRAMING
Timber framing must meet the requirements of NZS 3604 (2011) (Timber-framed buildings), or where an
alternative framing product is used (such as steel framing) strength and stiffness must be equal or greater
than the performance requirements as set out in NZS 3604 (2011).
6.3 BUILDING UNDERLAY
The building underlay used must also meet all the requirements stated in NZBC Clause E2/AS1 Table 23
(Properties of roof underlays and Wall Underlays). ITI Timspec recommend Sikaflex AT Fascade.
A Rigid Wall Underlay is required for EH wind zones.
6.4 FLASHING TAPE
The flashing tape used must meet all the requirements stated n NZBC Clause E2/AS1 section 4.3.11 with a
valid BRANZ Appraisal or CodeMark and suitable to be used with the wall underlay selected.
The flashing tape must be compatible with all materials that it is in contact with, specifically the building
underlay.
The building underlay used must also meet all the requirements state in NZBC Clause E2/AS1 Table 23
(Properties of roof underlays and Wall Underlays).
6.5 SEALANTS AND ADHESIVES
6.5.1 MODIFIED SILICONE OR CO-POLYMER CONSTRUCTION SEALANT
All construction Sealants are to be a modified silicone with a valid BRANZ Appraisal or CodeMark.
6.5.2 SELF-EXPANDING POLYURETHANE FOAM
All Self-expanding foams must be rapidly expanding polyurethane foams that bonds with all materials that
they will come into contact with. The foams must not shrink and must cure to an airtight, moisture resistant
seal.

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6.6 PEF ROD
PEF backing rod must be closed cell polyethylene foam complying with E1/AS1 section 9.1.6.
It should have a diameter 25% larger than the gap width and should be pushed into the gap with a blunt
tool.
6.7 METER BOX
Meter box penetrations have a higher risk of water ingress, and as such all possible steps should be taken
to minimise this risk. A good quality meter box manufactured by a leading NZ supplier will certainly help
this.
Meter boxes are to be manufactured from aluminium, hot-dipped galvanised steel, glass-reinforced plastic
or other suitable rigid, UV resistant, non-combustible material. They also must be coated on the inside and
outside surfaces with a material giving a hard, durable finish providing a service life of not less than 20
years.
The door must have a troughed lip around the front perimeter and if a drain is present is should be made in
a way to minimise water entry.
6.8 INTERNAL LINING
Internal Linings must be of a suitable size and material to provide bracing where needed and to act as an
adequate barrier to air flow.

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INSTALLING CAVITY BATTENS
7.1 CAVITY CONSTRUCTION
7.1.1 COMPLIANCE
Cavities must comply with NZBC Clause E2/AS1 paragraphs 9.1.8 to 9.1.9.4.
7.1.2 PRECAUTIONS
As solvents in LOSP treatments can affect bitumen based building papers, it is necessary to fillet stack
LOSP treated timber for 7 days after treatment to ensure that solvent has evaporated before contact with
any bitumen-based building paper.
7.1.3 FIXING (NON-STRUCTURAL) CAVITY BATTENS
Cavity battens are to be fixed over underlay to the studs with extra vertical battens to corners to support
flashing when required.
NOTE Fixing is only temporary for cavity battens as the weatherboard fasteners are used to
permanently fix the batten.
7.1.4 TOP OF WALL DETAIL
No ventilation shall be provided at the top of the cavity. Use a horizontal D4S profile (not a Cavibat batten)
at the top of the wall to close off the top of the cavity. This prevents damp air circulating from the cavity
space into interior spaces such as roof framing or eaves and is extremely important where the cavity
finishes beneath an area that is open to a roof space (such as a wall finishing under a soffit).
7.1.5 BOTTOM OF WALL DETAIL
Use a ‘Cavity Base Closure Flashing’ at the bottom of the wall to allow drainage and ventilation but prevent
the entry of vermin. This also applies where cavities end over a window, door or another opening. Ensure
building underlay laps over rear upstand of the cavity base closure or use flashing tape to seal the top of
the cavity base closure to the building underlay. An angle packer (or part board) may be required to support
bottom of lower weatherboard.

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FIXING DETAILS FOR WEATHERBOARD
8.1 INSTALLATION
8.1.1 FIXING METHOD - BEVELBACK WEATHEBORDS
Ensure correct nails are selected in accordance with the nail selection chart 8.1.2. below.
Nail placement is to be 35 - 40mm up from bottom edge of weatherboard. The nail must not penetrate the
underlapping (lower) board. Nail shank must be annular grooved.
Pre-drill all nail holes using a bit that is 0.3 –0.5mm smaller than the nail shank to prevent splitting, and
ensure a snug fit.
Nail on an upward angle to prevent water running down the nail through the cavity.
Ensure nail shank has a minimum framing penetration of 35mm for painted weatherboards.
Hand-drive all nails. Gun-driven nails should not be used as they may damage the surface of the timber or
cause splitting or crushing damage in the battens.
Flat head, pentagon head or crown head nails to finish flush onto, but not into, the face of the
weatherboard.
Jolt head nails must be punched just below the surface, spot primed and filled using a two-part high quality
non-shrinking filler, and sanded smooth, prior to painting.
Ensure weatherboards are set out to achieve correct 32mm overlap at join.
One board on any given wall elevation may need to be cut down to fit wall height. Do not extend or reduce
the 30mm lap requirement or ‘creep’ the boards to fit.
8.1.2 NAIL SELECTION CHART
Weatherboards
Nail Size
Material
Nail Head
Nail
Shank
Minimum Framing
Penetration
Painted
90 x 4.0 mm
Stainless Steel
(304 or 316)
Silicon Bronze
Jolt head
annular
grooved
to achieve
minimum 35mm
framing penetration
Refer NZBC Clause E2AS1 Table 24
Fixing lengths need to increase when installed over a rigid wall underlay to ensure minimum penetration of
fixing into the stud.

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INTER-STOREY CAVITY JUNCTION
9.1 DEFINITION
Cavities may be continuous up to two storeys or 7m in height (whichever is the lesser). Walls over this
height require an inter-storey junction to drain the cavity.

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WITHIN-BOARD JOINS (SCARF JOINT)
Use a within-board joint to join two shorter weatherboards together, to cover full wall width.
10.1 LIMITATIONS
A within-board join should not be placed where it is directly adjacent to another join, a junction, a corner or
a penetration i.e. stagger joins across the wall.
10.2 METHOD
Weatherboards may be joined by scarfing two boards together over a batten. Cut boards with a minimum
30-degree angle. Use an appropriate adhesive to bond the boards together and nail through the
overlapping board only. The nail should be 30mm from the edge of the join to avoid hitting the underlapping
board. Care should be taken to select and use two boards that are similar in grain and appearance, and
that have equal moisture contents; otherwise, one board may shrink or expand at a differing rate putting
stress on the joint.

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SITE CLEAN-UP
11.1 AT COMPLETION
Upon completion, the installer is to leave the site in a clean and tidy manner, including:
1. Replacing or repairing any damaged or marked items; and
2. Removing all rubbish, debris and unused items from the building site.
Any treated and/or coated timber off-cuts (e.g. cavity battens) or rubbish are to be disposed of in
accordance with local council requirements.

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ON-GOING MAINTENANCE
It is the building owner’s responsibility to ensure that the cladding system receives regular maintenance so
that it continues to perform at its required level.
12.1 MAINTENANCE INTERVAL
Maintenance should be called up at least annually, and more often in aggressive environments –coastal,
industrial, and geothermal as appropriate.
12.2 MAINTENANCE REQUIREMENTS
Regular maintenance is to include the following 5 steps:
1. Wash all exterior surfaces with low-pressure water to remove dust, dirt and other contaminants;
a. Extra attention should be given to areas that are not exposed to rain such as sheltered areas
below eaves;
b. Do not direct high-pressure water at any part of the cladding system as this may damage the
timber surface. Take care especially around sensitive junctions such as joinery surrounds
and other flashings where you must avoid forcing water past anti-capillary gaps and
flashings into the wall cavity.
2. Use a soft bristle nylon brush or broom with water and an appropriate cleaning agent (refer to paint
manufacturer for correct cleaning agent specific to their paint system) to remove stubborn or
persistent dirt and surface contaminants. Rinse thoroughly with water after the cleaning operation to
remove any excess cleaning chemicals. DO NOT use aggressive cleaning chemicals.
3. Inspect all surfaces and junctions for signs of damage, wear-and-tear, or coating breakdown. Where
coating surface has broken or eroded remedial action is required in accordance with the
requirements of the coating manufacturer.
4. Repairing or replacing any damaged or deteriorated items in order to preserve the weather
tightness of the building:
a. Small isolated areas of dry rot (highly unlikely) in timber can be cut out and filled then primed
and coated;
b. For larger areas of deterioration: remove and replace either the damaged section or the
entire board for any deteriorated timber boards (includes scribers, cover boards and
weatherboards). Prime and coat the replacements as required;
c. Other items (soakers, flashings and capping’s) may need to be replaced in their entirety.
5. Where a coating is applied, periodic recoating is required to ensure the integrity of the coating is
sustained. This will generally mean applying another exterior coat every 4 to 10 years (dependent
on the coating used and building location) after washing and maintenance.

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CONSTRUCTION DETAILS
FIGURE 13. 1 BC 106 PAINT FINISH WITH STANDARD CAVITY FIX