Refer to ~ for ~.

Refer to the general section 1232 INTERPRETATION & DEFINITIONS for abbreviations and definitions used throughout the specification.

The following abbreviations apply specifically to this section:

Refer to the general section 1233 REFERENCED DOCUMENTS.  The following documents are specifically referred to in this section:

Health and Safety at Work Act 2015

Manufacturer's and supplier's documents related to this section are:

Stoanz Ltd documents relating to work in this section are:

• Sto Specification SS-303 StoLite Stucco System
• Sto Specification SS-303R StoLite Stucco System - Reclad
• Sto Specification SS-808 StoStucco Render System
• Sto Specification SS-808R Sto Stucco Render System - Reclad
• Sto Specification SS-806 StoStucco Roughcast System
• StoLite installation details
• StoStucco installation details
• Sto Technical Data Sheets
• BRANZ Appraisal 468 - StoLite Stucco Cladding System
• BRANZ Appraisal 605 - StoStucco Plaster Cavity System
• BRANZ DC1182 - Durability Testing of the Sto Flexyl Waterproofing Membrane
• BRANZ STO812-V2 - Comparative small hard body impact tests
• BRANZ FH4007 - Cone Calorimeter Test on Sto Stucco Plaster System over Stainless Steel Lath
• BRANZ FH4064 - Cone Calorimeter Test on Sto Lite Cladding System

Materials and execution to Stoanz Ltd specification except where varied by this specification and supported by architectural detailing.

Copies of the above literature are available from:

Warrant this part of the work under normal environmental and use conditions against failure of materials and execution.  The Sto Contractor must complete the Sto Quality Assurance Schedule, Sto Contractor PS3 form and Workmanship Guarantee.  The StoLite Stucco Cladding System & StoStucco Render System when serviced is warranted as follows:

StoService Assurance is a comprehensive guide to maintaining the cladding with service inspections carried out every 2.5 years by the Sto Contractor to ensure the exterior building elements are cleaned and are performing in accordance with the Sto Material Warranty and Sto Contractor Guarantee requirements.

Use only Sto Registered Contractors to apply the Sto render systems.

Substitutions are not permitted to any specified Sto render system.

Provide protection systems as required by the manufacturer to protect fresh or uncured render from adverse weather conditions.

Allow to inspect the whole of the work at each stage.  Determine a programme for inspections including notification when each part and stage of the work is ready for inspection prior to the work commencing.

If requested permit representatives of StoanzLtd to inspect the work in progress and to take samples of their products from site.  Refer Sto product manual.

Refer to the general section 1270 CONSTRUCTION for details of how samples will be reviewed and how instructions to proceed will be given.  Provide the following samples for review:

Provide Sto Service Assurance Maintenance documents with the Sto Warranty upon practical completion of the contract for issuing to the building owner.

Refer to the requirements of the Health and Safety at Work Act 2015 and WorkSafe:  Guidelines for the provision of facilities and general safety in the construction industry.

If the elimination or isolation of potential hazards and risks is not possible then minimise hazards and risks in this work on site by using the proper equipment and techniques as required in the Health and Safety at Work Act and Worksafe.  Supply protective clothing and equipment.  Notify employees and others on site of the hazards and risks, and put into place procedures for dealing with emergencies.  Obtain from Stoanz Ltd the material safety data sheets (MSDS) for each product to be used.  Keep material safety data sheets on site and comply with the required safety procedures.

Provide the producer statement from the Sto Contractor in a form meeting the requirements of the Building Consent Authority.

The work covered by this part of the specification has been designed and constructed to meet the NZBC durability requirement of 15 years with a serviceable life in excess of 30 years when maintained.  Refer to the following:

BRANZ Appraisal 468 - Sto Lite Cladding System

BRANZ Appraisal 605 - StoStucco Plaster Cavity System

Provide ongoing maintenance instructions required to meet the performance requirements of the NZBC B2/AS1 Durability.

Accept responsibility for the structural and weather-tight performance of the exterior render application.

Refer to MANUFACTURER/SUPPLIER DOCUMENTS for details of BRANZ test results.

Lightweight cement basecoat render in a bag.  The material contains mineral aggregates water retention agents, adhesive compounds, EPS beads and other additives to form a straight, solid basecoat render.

Synthetic reinforcement render in a pail with a calibration grain. A white non cement flexible meshing render containing organic fillers and fibres bound in a polymer dispersion to form a malleable crack resistant intermediate render with excellent adhesion qualities.

Alkali-resistant 165g/m² fibreglass mesh in 50 metre rolls.

Six different synthetic coloured finishing renders (as selected) in a pail.  Containing organic aggregates and fibres bound in a polymer dispersion with enhancement agents and colouring pigments.  Refer to SELECTIONS for texture and colour.

Coloured facade paint, with natural looking matt finish, hard, durable coating with excellent resistance to weathering.  Select acrylic, heat-reflective or mineral options.  Refer to SELECTIONS for paint and colour.

Clear, invisible Silane sealer for ease of cleaning and added protection against staining of coloured sponge finishes (Note: where a clear coating is required contact Stoanz Ltd).

Proprietary uPVC flashing system fixed over the framing wall underlay before the installation of the cavity battens and stainless steel lath.

Nominal 50mm x 25mm timber treated H3.1 cavity battens installed with 75mm x 3.15mm hot-dipped galvanized flat head nails.

Stainless steel lath 2400mm x 700mm made from AISI 304 stainless steel welded into 50mm x 40mm squares with double strength fixing wires at 150mm horizontal centres incorporating an inter woven absorbent perforated cardboard sheet with a backing sheet of overlapping bitumen building paper.

Lightweight cement basecoat render in a bag.  The material contains mineral aggregates water retention agents, adhesive compounds, EPS beads and other additives to form a levelling/straightening, solid basecoat render.

Synthetic reinforcement render in a pail with a calibration grain.  A white non cement flexible meshing render containing organic fillers and fibres bound in a polymer dispersion to form a malleable crack resistant intermediate render with excellent adhesion qualities.

Alkali-resistant 165g/m² fibreglass mesh in 50 metre rolls.

Six different synthetic coloured finishing renders (as selected) in a pail. Containing organic fillers and fibres bound in a polymer dispersion with enhancement agents and colouring pigments.  Refer to SELECTIONS for texture and colour.

Coloured facade paint, with natural looking matt finish, hard, durable coating with excellent resistance to weathering.  Select acrylic, heat-reflective or mineral options.  Refer to SELECTIONS for paint and colour.

Clear, invisible Silane sealer for ease of cleaning and added protection against staining of coloured sponge finishes (Note: Where a clear coating is required contact Stoanz Ltd).

Head jamb sill and any other required flashings made from powder coated aluminium, stainless steel or uPVC for both recessed and faced fixed timber, aluminium and uPVC joinery to NZBC E2/AS1, 4.0 Flashings and masonry construction requirements.

Sto uPVC flashings for weatherproofing the cladding at transitions, junctions and terminations.

Sto 8mm or 12mm uPVC control joint, including 12mm for inter-storey joints.

BRANZ appraised modified silicone (MS) sealant compatible with uPVC.

Keep Sto bagged render products dry in transit.  Take delivery of Sto render products in good condition.  Reject all damaged materials and immediately notify supplier in writing.

Deliver all materials in original unopened packaging with labels intact.  Provide dry, frost free storage on site, stack carefully, protect from mechanical and vermin damage.  Keep bagged render dry and off concrete or damp surfaces.

Carry out rendering in accordance with the project and Sto specification and details under conditions which will not adversely affect the finished work.

Before commencing, apply protective masking to all joinery, pipes, roofs and adjacent surfaces or areas likely to be damaged or marked.  Use drop sheets to keep the working areas clean.  Remove any material splatter from finished work or adjacent surfaces immediately.

Before rendering is commenced, remove any surface contaminants, e.g. dust, debris, oils, greases, retarders and loose material.  Treat any adhesion impairing surfaces, paint from already painted surfaces, and loose material.  Leave the surface dust free and clean.  Make good any defects in the background which may adversely affect the quality of the render coating.

Ensure any damaged fibre cement sheet or lath is replaced and that the required number of fixings have been used.

Comply with the Sto CAD flashing details.  Penetrations such as fixing brackets, pergolas, roofs and pipes shall be adequately flashed and waterproofed prior to render application.  Carry out to the required standard of execution to ensure water does not penetrate the exterior facade when complete.

All penetrations such as waste pipes, plumbing piping and electrical wiring in uPVC conduits must be installed with a minimum 5° downward slope, through the Sto render system, and be sealed using a double application of MS sealant at the backing/basecoat render and again at the mesh coat.

Before commencing work confirm the layout of control joints and other visual detailing of the finished work.

Where shown on the drawings and to Stoanz Ltd requirements, insert vertical Sto flexible uPVC control joints aligned with the base sheet set out at maximum 5.4m centres for StoLite and at 8.0m centres for StoStucco.  Reflect exposed control joints through the render.

Form horizontal inter-storey joints in the StoLite System at all inter-storey transitions or every 5.4m on continuous studs (excluding gables - maximum 7.0m).  Horizontal drained junctions are required at the third storey or at 7.0m in accordance with E2/AS1 Paragraph 9.1.9.4(b).

On StoStucco, horizontal inter-storey junctions are only required when unseasoned timber joists are used.  Where dry seasoned joists, LVL’s or proprietary joists are used, a drained inter-storey junction is required at the third storey or at 7.0m in accordance with E2/AS1 Paragraph 9.1.9.4(b).

Form vertical control joints using a proprietary Sto uPVC 8mm control joint, and inter-storey control joints using a proprietary Sto uPVC 12mm control joint.  Drained joints shall be formed using an E2/AS1 compliant metal flashing as per the Sto CAD details.

Install a metal capping on parapet tops with a minimum slope of 5°.  On LevelLite rendered balustrades with a minimum slope of 10° apply Sto Flexyl / meshed waterproofing encapsulating the mesh to a minimum thickness of 1.5mm and extend 75mm up and down adjacent vertical render surfaces and cover any joints by a 50mm minimum.  Once dry apply StoArmat mesh coat followed by Stolit render finishing coats.

Refer to SELECTIONS for type and colour.

Ensure the main contractor and the sub trades are aware of their responsibilities relating to the required provision of weather tight details at all junctions, penetrations and transitions including any blockings required for support (see www.sto.co.nz for details).

Do not commence work until openings and apertures have been cut, joinery, pipes, fixtures, fixing pads and plugs, brackets and wiring conduits have been installed, and flashings and other preparations are complete.

All defects in the substrate must be rectified prior to application of the render coatings.  Ensure that substrates and adjoining surfaces are, after the preparation called for in this section, of the required standard by Stoanz Ltd.

Install all StoLite uPVC ClipOn foot trays and joinery flashings to fibre cement sheets and joinery.  Glue into position with construction adhesive prior to render application commencing.  All fixings and installation of the Sto uPVC joinery flashings, ClipOn foot trays, finishing edges and profiles to be in accordance with the Stoanz Ltd details.

Sto pre-meshed UPVC corner beads to be installed on corners and edges as required, set in the basecoat and reinforce with the StoArmat mesh coat unless stainless steel corner angles are being used.

Mesh all joints in the fibre cement sheets with 150mm wide Sto adhesive mesh before the basecoat render is applied.

To clean dry backing boards, set polystyrene screed guides as required, stainless steel corners, StoLite uPVC ClipOn foot trays, joinery uPVC jamb and sill flashings and drip edges as required and allow to set.  Apply the LevelLite basecoat render at nominal 8mm thickness and close off wet render with an h shaped rule.  Allow to set up and cut back the LevelLite with a feathered straight edge to achieve a level plane surface free of hollows and deviations.  Apply enough LevelLite render to achieve a finished coat thickness of 8mm after screeding.

Apply over the dry basecoat render one coat of StoArmat reinforcement render at approximate thickness of 2mm.  While the render is still wet, lightly embed Sto mesh, ensuring adjacent drops of mesh are overlapped by a minimum of 75mm and the mesh is encapsulated into the render.  Allow to dry and apply one further coat of StoArmat at an approximate thickness of 1 - 1.5mm.  Once dry remove any slight ridging with a Sto rasp.

After the completion of the StoArmat mesh coat, all junctions between the joinery and around penetrations, flashings and other similar details to be sealed with a minimum 6mm bead of MS sealant.

Apply selected Stolit K or MP coloured finishing render with a steel trowel gauging to the thickness of the aggregate size and finish with a plastic float to the requisite pattern.  Apply Stolit MP or MP Natural in two coats and finish with a float and judicial use of a damp sponge.

Apply one coat of StoColor matt facade paint (two coats required for StoColor X-black) tinted to the selected colour, on Stolit K render or S-Protect SC easy clean sealer on Stolit MP finishes.

Ensure the main contractor and the sub trades are aware of their responsibilities relating to the required provision of weather tight details at all junctions, penetrations and transitions including any blockings required for support (see www.sto.co.nz for details).

Do not commence work until openings and apertures have been cut, joinery, pipes, fixtures, fixing pads and plugs, brackets and wiring conduits have been fixed and flashings and other preparations are complete.  Install over the wall underlay the StoStucco uPVC flashing system, incorporating joinery flashings, foot trays, soffits edges and dissimilar material junctions with back flashings as required.

Once the flashings are in place install nominal 50mm x 25mm H3.1 treated timber cavity battens to all studs using 75mm galvanized flat head nails at 300mm centres.  Install Sto stainless steel lath with writing facing out.  Overlap sheets in brick pattern and fix with an air driven stapler using 16g - 32mm stainless steel staples at 150mm centres on fixing wires to StoStucco Specification & CAD details.

Check the lath has been installed correctly over the StoStucco flashing system.  The screed guides attached to the flashing system are to clearly define the plane of the basecoat render applications.

To clean dry Sto Lath apply a nominal 8-10mm thick levelling coat of LevelLite render by pump, and trowel to close off the lath, combing the finish.  While the render is still wet, set stainless steel corners at externals corners to define the plane and leave to dry.

To clean dry scratch coated lath apply the LevelLite basecoat render by pump at a nominal 8mm thickness to level the guides.  Close off wet render with an h shaped rule.  Allow to set up and cut back the LevelLite with a feathered straight edge and Sto rasp to achieve a level plane surface free of hollows and deviations.  Apply enough LevelLite render to achieve a flat plane between the Sto PVC flashing guides and external corner angles.  Once dry remove all ridges and excess render from the flashing facings so that the StoArmat mesh coat can lock into the flashing system.

Apply over clean, dry basecoat render one coat of StoArmat reinforcement render at an approximate thickness of 2mm.  While the render is still wet, lightly embed Sto mesh, ensuring adjacent drops of mesh are overlapped by a minimum of 75mm and the mesh is encapsulated into the render.  At joinery sills and jambs, cut excess mesh back and install Sto pre meshed edges into the rebates.  Allow to dry and apply one further coat of StoArmat at an approximate thickness of 1 - 1.5mm.  Once dry remove any slight ridging with a Sto rasp.

After the completion of the Sto Armat mesh coat, all junctions between the joinery and around penetrations, flashings and other similar details to be sealed with a minimum 6mm bead of MS sealant.

Apply selected Stolit K or Stolit MP coloured finishing render with a steel trowel gauging to the thickness of the aggregate size and finish with a plastic float to the requisite pattern.  Apply Stolit MP or MP Natural in two coats and finish with a float and judicial use of a damp sponge.

Apply one coat of StoColor matt facade paint (two coats required for StoColor X-black) tinted to the selected colour, on Stolit K render or S-Protect SC easy clean sealer on Stolit MP finishes.

Remove debris, unused materials and elements from the site relating to render system application.  Replace damaged, cracked or marked elements.  Leave the whole of this work to the required standard.

Arrange for a final inspection of the entire finished cladding by the project assessor immediately after completion of the wall cladding work and make good any defects or subsequent damage immediately.