Masonry Render System over Brick - Porotherm Masonry Render System
General
Description of Works/Specification Notes
This specification deals with Resene Construction Systems Masonry Render System applied over Porotherm Block. The system incorporates the application of a mineral texture finish.
Building Code Compliance
If the project has a building consent then the following clauses apply.
B1 – Structure
This specification complies with the requirements as set out in B1 – Structure which requires buildings, building elements and sitework to withstand the combination of loads and physical conditions they are likely to experience during construction, alteration and throughout their lives. Loads and physical conditions include self-weight, temperature, water, earthquakes, snow, wind, fire.
B2 – Durability
This specification complies with the requirements as set out in B2 – Durability which must always be considered when demonstrating compliance with each of the clauses of the Building Code. It ensures that a building throughout its life will continue to satisfy the performance of the Building Code. It confirms the use of materials that will remain functional throughout the specified intended life of the building, but not less than 50, 15 or 5 years
This cladding system meets the expected durability of the NZBC of at least 15 years
E2 – External Moisture
This specification complies with the requirements as set out in E2 – External Moisture which demonstrates External roof, wall claddings and external openings will prevent external moisture from causing undue dampness or damage.
F2 – Hazardous building materials
This specification complies with the requirements as set out in F2 – Hazardous building materials which safeguards people from illness and injury from quantities of gas, liquid, radiation and solid particles caused by exposure to building materials
On Going Maintenance Instructions
Provide ongoing maintenance instructions required to meet the performance requirements of the NZBC.
Building Consent Authority Requirements
All the appropriate inspections are to be carried out by a BCA representative and that it complies with the NZBC requirements.
Documents
Abbreviations
The following abbreviations are used throughout this work section:
- BCA – Building Consent Authority
- LBP – Licensed Building Practitioner
- PPCS – Proprietary Plaster Clading System
- MPNZA – Master Painters of New Zealand Association
- MSDS – Material Safety Data Sheet
- NZBC – New Zealand Building Code
Manufacturers Documents
Copies of the above relevant company documents referred to in this specification are available at;
Resene Construction Systems
Web: reseneconstruction.co.nz
Telephone: 0800 50 70 40
No Substitutions
Substitutions are not permitted to any specified Resene Construction Systems system. Materials and execution to Resene Construction Systems specification except where varied by this specification and supported by architectural detailing.
Qualifications
Use only LBP registered plasterers licensed to apply the Resene Construction Systems exterior render systems.
Documentation
Finish Sample
Submit one 300 mm x 300 mm sample of the selected texture finish and colour for approval on request by the main contractor or specifier. Obtain signature of acceptance on sample and return to the Registered Plasterer.
Maintenance Instructions
Provide Resene Construction Systems Maintenance Guide on or before practical completion of the contract for issuing to the building owner. Resene Construction Systems Maintenance Guide to be provided on request.
Producer Statement
If the project has a building consent then a producer statement shall be supplied by the plasterer in the form as required by the BCA.
Health and Safety
Refer to the requirements of the Health and Safety in Employment Act 2015 and Worksafe NZ: 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 MPNZA Painters hazard handbook. Supply protective clothing and equipment. Inform employees and others on site of the hazards and put into place procedures for dealing with emergencies. Obtain from Resene Construction Systems the Material Safety Data Sheets for each product. Keep sheets on site and comply with the required safety procedures. Confirmation at the start of the project as to whether a Site Specific Safety Plan is to be produced by the Registered Plasterer prior to works starting.
Warranty
Warrant this system under normal environmental and use conditions against failure. Resene Construction Systems system warranty.
Materials: by Resene Construction Systems – 15 Years Materials only
Execution: by Registered Plasterer – 5 Years Workmanship only
OnSite Assistance
Allow to inspect the whole of the work at each stage. Determine a programme for onsite assistance including notification when each part and stage of the work is ready for inspection prior to the work commencing. Permit representatives of Resene Construction Systems to inspect the work in progress and to take samples of their products from site if requested.
Components Used
Mono Render
- Supplied in 20kg Bags
Mesh – Blue (1200mm wide)
- Alkali Resistant 6mm x 5mm Weave mesh supplied in 50m rolls
Ezytex Float
- Polymer-modified cement-based dry plaster mix. Supplied in 20 kg bags
Resene Limelock
- Water based acrylic polymer dispersion. Supplied in 10 litre pails.
Installation/Application
Check and Prepare Masonry / Clay brick veneer Substrate
Preparation based on new substrate installations.
Preliminary Checks
Check that all exposed surfaces of the substrate are straight, plumb, and undamaged. If any loose bricks are identified, they must be removed and replaced. Ensure that pointing has cured according to the manufacturer’s specifications prior to render application.
Wall Alignment
Using a straight edge, check joints are smooth and that the wall is flat and true. The Render coating is not designed to straighten deviations that exceed the specified Rockcote Render System thickness.
Weep Holes
Weep holes must be kept clear of Render unless an alternative solution is accepted by the BCA.
Builder Supplied Flashings
Make sure all builder-supplied flashings are in place. The architectural drawings provide a list of possible flashings.
RCS Flashing Installation
Refer to the flashings as outlined within the Resene Construction Systems Specification.
Control/Expansion Joint Setouts
For more information about control joints refer to the technical note on the Resene Construction webpage at the following link https://reseneconstruction.co.nz/control-joints/
The main contractor/substrate installer is responsible for all control joints, which must comply with the substrate supplier’s specifications.
Clay bricks
Control joints shall be included at locations specified by the brick manufacturer.
Concrete bricks
Control joints shall be included as specified in the New Zealand Concrete Masonry Manual and in any other locations specified by the brick manufacturer.
Clean Surface
When the substrate has been left for a period of time, dust and dirt may build up on the surface. This contamination must be removed prior to render application.
Masking
Before applying the render, masking must be applied to all joinery, pipes, roofs, and all areas likely to be marked by the render. Use drop cloths and ground covers to keep the working areas clean.
Colour selection
For more information about light reflectance values refer to the technical note on the Resene Construction webpage at the following link https://reseneconstruction.co.nz/light-reflectance-values/
Improve adhesion
If Render is being applied to the masonry wall, wet the wall down, or apply a solution of Rockcote Acrylbond and Water – ratio1 part Acrylbond : 4 parts water to minimise the suction of the substrate.
Allows the render to maintain moisture content for longer, providing greater working time. This process assists with the initial hydration / curing of the render application.
Rockcote Mono5 Base Coat
Surface Preparation
Ensure surface is clean, sound, dry and free from dust, dirt, grease, mould and lichen.
Application
Plaster can be applied with a steel trowel, pump or broad-knife at approximately 3-5mm thick (3m2 per bag). Apply with firm pressure lay in mesh and trowel well to embed mesh (for base coat only). Apply plaster only when the temperature is between 5°C and 30°C and will be in that range for the 24 hours period following application.
Curing:
Render should be protected from hot drying winds and direct sunlight for the first 16 hours. Protect newly applied plaster from rain and water run off for the first 24 hours.
Resene Construction Systems Mesh (Standard Weave)
General
Measured and cut slightly longer than the height/length of the area to be covered.
Application of Fibreglass Mesh
Apply the pre-measured mesh from the top of the wall.
Press the fibreglass mesh into the render mix with a steel trowel starting at the centre and working outwards towards the sides, so that it is completely embedded with the render mix forced right through the mesh holes.
Ensure there are no wrinkles or trapped bubbles in the mesh and that it is fully embedded just below the surface of the render.
Do not embed the leading edge of mesh as this locates your next mesh layer.
Mesh must not be exposed but retained as close to the surface as possible.
Overlap mesh 100 mm with the adjacent drop of mesh, and trowel to embed together.
Ensure the fibreglass mesh covers all exposed areas of the substrate, including any recesses around the exterior joinery and internal corners.
Fibreglass Mesh must be bought to the outside edge of all Flashings.
Apply 450 x 150 mm strips of fibreglass mesh `butterflies’ diagonally at every corner of openings for window and door joinery, meter boxes etc.
After the render mix has cured, trim off excess length accurately against the flashing edge.
Rockcote Mono5 Level/Second Coat
Surface Preparation
Ensure surface is clean, sound, dry and free from dust, dirt, grease, mould and lichen.
Application
Plaster can be applied with a steel trowel, pump or broad-knife at approximately 2-3mm thick (6m2 per bag). Apply plaster only when the temperature is between 5°C and 30°C and will be in that range for the 24 hours period following application.
Curing:
Render should be protected from hot drying winds and direct sunlight for the first 16 hours. Protect newly applied plaster from rain and water run off for the first 24 hours.
Plaster Systems Ezytex Float Texture Finish
Application:
Plaster is applied not less than 1mm (8m2 per bag) with a steel trowel to a flat finish then float using a circular action to an even texture over the following five minutes with a plastic float. Apply plaster only when the temperature is between 5°C and 30°C and will be in that range for the 24 hours period following application.
Curing:
Plaster should be protected from hot drying winds and direct sunlight for the first 16 hours. Protect newly applied plaster from rain and water run off for the first 24 hours. It is able to be sealed while the finish is still green.
Resene Limelock Sealer
Application
Apply to trowelled plasters immediately after final trowelling (Dependent on surface porosity, typically 5-8m2 per litre). Apply one coat of Resene Limelock over the fresh substrate by commercial grade knapsack sprayer, spray, long pile roller or brush and allow to dry. Evenly coat all fresh surfaces to ensure uniform curing and that free lime cannot be transferred through weak points.
Resene AquaShield (2 Coats)
Important:
This specification must be read in conjunction with the Resene Construction Systems technical drawings.
No alteration to the Resene Construction Systems RenderSpec® is permitted.
All Technical Data Sheets are available at https://reseneconstruction.co.nz/technical-library/technical-data-sheets/
All Safety Data Sheets are available at https://reseneconstruction.co.nz/technical-library/safety-data-sheets/
