ROCKCOTE APPLICATION SPECIFICATIONS

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Jointing System < Fibrous Cement Sheet> <Visibility of joints in Fibrous Cement Sheeting >
Quick Render over <Power Panel>
Rockcote Cement Render over <Previously painted masonry >
Rockcote PM100 Render over <Lightweight Building Systems><Foamular-Metric >
Polymer Render over <Previously painted surfaces>
Polymer Render & Polymer Render Hi Build over <PVC Substrates>

SURFACE PREPARATION

• Ensure board is fixed as per manufacturer's specifications.
• All surfaces must be clean and free from dirt, dust, oil, and any loose materials.
• Stainless steel or PVC angles are fitted to external corners using flat head galvanised nails.
• Seal between windows and doorframes, using a flexible polyurethane-jointing compound.
• A soft brush should be used to remove dust from recessed joints.
• Rockcote Hard Patch is applied to the joints using a steel trowel, spatula or broad knife. Add cement to Hard Patch as per its Specification Sheet and mix thoroughly.
• The Rockcote fibreglass reinforcing mesh (non-adhesive 50mm x 120gms/m2 alkaline resistant) is embedded into the surface of the patching compound while it is still wet.
• After the first coat has dried and any shrinkage taken place a further application of Rockcote Hard Patch may be applied to bring the joint flush with the surface of the cement sheeting.
• Allow to cure for at least 24hrs before applying the Rockcote primer. The Rockcote primer is applied using brush, roller or suitable spray equipment.
• It is imperative that the wall is thoroughly sealed with Rockcote primer before applying the textured finish or the patched areas will shine through the textured finish.

The primer must be applied undiluted at the relevant rate as per the Primer Specification sheet and allowed to dry for at least 6hrs before applying the textured finish.

BASE APPLICATION

Rockcote Polymer Render is applied in one or more coats as a base coat, using a steel trowel, to an approximate thickness of 1.5mm - 4mm. This is then floated to an even finish using a plastic float. The surface is now ready to accept a textured finish. Note that film thicknesses greater than 2 mm will require considerable time to dry.  Ensure that moisture is less than 15% at the thickest location before applying decorative topcoats. 

Certainly the visibility of joints detracts significantly where the architectural intention is to emulate an uninterrupted masonry wall expanse achieved through use of lower cost pre-fabricated material.

Is the expectation realistic?

Much has been written on the effect of glancing light on interior building surfaces, such as fibrous plaster and gypsum board. In a report on this aspect, the CSIRO advises that for an uninterrupted smooth finish, the surface must be absolutely flat and in practice no building substrates are. (CSIRO 1992 5 th Edn.: Illumination and Decoration of Flat Surfaces).

This is most evident on joints, and the problem of joint visibility under applied finishes is well recognised.

This situation can be exactly translated to exterior wall surfaces.

As well as the increased use of FC sheeting, there is a fashion trend towards the finer textured “Mediterranean” style finishes and a decreasing use of eaves and other components which cast shadows and interrupt sunlight striking the surface.

Again, it is in the joints where the problem manifests itself.

For any number of reasons, including frame movement; sheet alignment; porosity of substrate; as well as jointing products and methods used, the actual joint may be slightly (several microns) raised or lowered compared to the adjoining sheets and/or have a different absorption factor.

Where the applied finish is a heavier, high profile texture or flat (no gloss) coating, the light is diffused and unevenness of the substrate is disguised.

With the fine textures and glossier finishes, even down to satin and low sheen, visibility of joints is a frequent result.

This situation must be accepted as part of the overall building system employed and does not constitute failure of the applied finish or untradesman-like application.

The inclusion into building design of visual breaks such as profiles and/or

expansion joints assists not only with reducing the effect of glancing light, but also provides natural day-work joints for applicators to eliminate overlapping areas, which themselves are highlighted under side light conditions.

The selection of higher texture finishes and lower gloss top-coats also minimises the problem by diffusing the glancing light, but it should be noted that “flat” or no-gloss paints and membranes compare unfavourably with the glossier versions in dirt/mould pick-up, water resistance and longer term durability.

Surface Preparation

Clean down surface removing all dirt, grease, oil, silicone, mould & fungi. Check the adhesion of the existing paint on every wall and at least every 3 metres over the proposed application areas. Any loose or peeling paint should be scraped back to a firm & sound substrate. Apply an alkali-resistant, penetrating primer /sealer if the old paint is oxidized or chalky.

Apply key coat & render as below to a test area at least 1 m square. After min. 48 hrs drying, and if the moisture level is less than 15% WME, test the adhesion by trying to chip off the render.

Ensure that the rest of the building is finished with the same paint & that some areas have not been treated with water proofers or hydrophobic sealers that may impair adhesion.

APPLICATION

Apply key coat as per Technical Specification Sheet, filling the mortar joints & providing a thin layer over the surface of the brick or block.

Apply Rockcote Render System using PM100 or Thin Section Render, as per relevant Technical Specification Sheets.

INDEMNITY

Rockcote warrants the adhesion of the key coat to the pre-existing paint if the steps described under Surface Preparation above have been followed. Rockcote is not responsible for the pre-existing paint coming away from the substrate.

SYSTEM:
Rockcote Reinforced Render System.

This is a generic coating specification applicable to polystyrene walling systems including:

• Perform Guard ® “Grey Board”
• Green Board
• Exin Building Panel
• Quik'n Tuff Panel
• Foamular-Metric

Note: We do not recommend Rockcote pre-bagged cement render products over cement sheeting including James Hardie Blue Board and its equivalents.

SURFACE PREPARATION

All surfaces should be clean and free from dirt, dust, oil, silicone and/or any loose materials before application.

APPLICATION

Important points to note.

• The cement render is Rockcote's PM100 Render.
• The base coat in every case is the Rockcote Reinforced Render System, with the reinforcement just below the surface of the render.
• Reinforcement strips 300mm x 200mm are applied and must be embedded into the PM100 Render at 45 degrees across the resurgent corners of all openings. This reinforcing should be placed on the board surface prior to rendering.
• Rockcote PM100 Render is applied at 4 – 6mm dry film thickness (DFT). At this point, the render is leveled and straightened using an aluminium ‘H' section or Darby.
• The fibreglass reinforcing mesh* is embedded into the wet PM100 Render just below the outside surface of the render not close to or touching the substrate.
• With Exin Building Panels and extruded polystyrene panels (eg Foamular-Metric) a key coat consisting of minimum 35% Acrybond, 65% clean water mixed with PM100 to form a slurry must be applied to the entire surface and allowed to cure for 24 hrs before the PM100 and mesh is applied.
• The fiberglass mesh must overlap at joints by at least 50mm and must overlap the outside edge of all beading.
• A further light skim may be applied to achieve the desired finish. This must be done as a single coat system i.e. before the PM100 has dried. The surface can be trowelled or floated to make the substrate suitable for the next application.
• The reinforced PM100 Render must be overcoated with a Rockcote acrylic render (eg Polymer Render) or an acrylic textured coating (eg Santa-Fe, Trowel-On, Finecote, Sandcote) to a minimum dry film thickness of 1mm.
• The selected top coat(s) eg. Armour, Toscani, Render Paint are then applied (s ee Rockcote Specification “ Performance Characteristics of Rockcote Render Systems [RR Systems] ” for information on categories of finish).
• Film builds, re-coat times etc are as per specification for the products selected.

NB : To avoid cracking and other problems, there can be no deviation from the above, particularly in the positioning of the fibreglass mesh and in the application of not less then 1mm dry film thickness of acrylic render or acrylic textured coating. i.e. Do not apply top coats of Render Paint, Toscani, Armour etc directly over the PM100.

*Fibreglass Reinforcing Mesh

The reinforcing mesh must be Rockcote alkali resistant glass fibre mesh, minimum weight 150gms/m2 with a maximum mesh size of 4.5mm x 4.5mm.

Indemnity

The application of Rockcote PM100 Render is a specialist procedure and should only be carried out by a skilled and experienced applicator and in accordance with our technical specifications.

Due to our policy of continuing product improvement Rockcote Enterprises Pty Ltd reserves the right to change these specifications without further notice.

SYSTEM:

Rockcote Reinforced Render System over Foamular Metric.

SURFACE PREPARATION

All surfaces should be clean and free from dirt, dust, oil, silicone and/or any loose materials before application. A key-coat slurry made with a mixture of a minimum of 25%:75% Rockcote Acrybond/Water added to Rockcote PM100 is applied to the Foamular Metric panel by trowel or bagging and allowed to dry for a minimum of 24 hours before application of subsequent PM100 coats.

APPLICATION

Important points to note.

• The cement render is Rockcote's PM100 Render.
• The base coat in every case is the Rockcote Reinforced Render System, with the reinforcement just below the surface of the render.
• Reinforcement strips 300mm x 200mm are applied and must be embedded into the PM100 Render at 45 degrees across the resurgent corners of all openings. This reinforcing should be placed on the board surface prior to rendering.
• Rockcote PM100 Render is applied at 4 – 6mm dry film thickness (DFT). At this point, the render is leveled and straightened using an aluminium ‘H' section or Darby.
• The fibreglass reinforcing mesh* is embedded into the wet PM100 Render just below the outside surface of the render not close to or touching the substrate.
• The fiberglass mesh must overlap at joints by at least 50mm and must overlap the outside edge of all beading.
• A further light skim may be applied to achieve the desired finish. This must be done as a single coat system i.e. before the PM100 has dried. The surface can be trowelled or floated to make the substrate suitable for the next application.
• The reinforced PM100 Render must be overcoated with a Rockcote acrylic render (eg Polymer Render) or an acrylic textured coating (eg Santa-Fe, Trowel-On, Finecote, Sandcote) to a minimum dry film thickness of 1mm.
• The selected top coat(s) eg. Armour, Toscani, Render Paint are then applied (s ee Rockcote Specification “ Performance Characteristics of Rockcote Render Systems [RR Systems] ” for information on categories of finish).
• Film builds, re-coat times etc are as per specification for the products selected.

NB : To avoid cracking and other problems, there can be no deviation from the above, particularly in the positioning of the fibreglass mesh and in the application of not less then 1mm dry film thickness of acrylic render or acrylic textured coating. i.e. Do not apply top coats of Render Paint, Toscani, Armour etc directly over the PM100.

*Fibreglass Reinforcing Mesh

The reinforcing mesh must be Rockcote alkali resistant glass fibre mesh, minimum weight 150gms/m2 with a maximum mesh size of 4.5mm x 4.5mm.

Indemnity

The application of Rockcote PM100 Render is a specialist procedure and should only be carried out by a skilled and experienced applicator and in accordance with our technical specifications.

Due to our policy of continuing product improvement Rockcote Enterprises Pty Ltd reserves the right to change these specifications without further notice.

Surface Preparation

All surfaces should be clean and free from oil, dirt, dust or silicone. R emove any loose paint and contaminants from the surface prior to application of Rockcote Polymer Render.

APPLICATION

Apply Polymer Render using a metal hawk and trowel to the wall surface. Depending on the style of finish required, tools such as a plastic float will give a smooth rendered finish whilst the use of a sponge will give a sandy finish.

To achieve a smooth rendered finish, first apply one tight coat of Polymer Render off the trowel to fill the raked joints around the brick or block and allow to dry for 6-12 hours before over coating.

Apply a second coat of Polymer Render up to 4mm in thickness and bring to a floated finish using a timber or plastic float. Allow the surface to take up enough to lightly sponge the surface to a nice sandy finish and allow to dry for at least 24-48 hours before over coating.

This is a generic coating specification applicable to PVC walling systems including:Dincel

SURFACE PREPARATION

All surfaces should be clean and dry as per data sheet for the primer being used.

APPLICATION

Important points to note.

• WARRANTY. Warranty is valid only if product is applied by a skilled & experienced applicator and strictly in accordance with film-build and other specifications.
• Texprime must be Version 14 to ensure adherence to the Armawall Sealer/ Bonder. Other versions need to be checked for adherence by Rockcote Technical Dept.
• Polymer Render & Polymer Render Hi Build are best applied as two or more coatings to thicknesses described in the relevant Specification Sheet.
• After each coat, a long straight edge should be used to determine whether another coat is needed to level out surface undulations.
• The maximum depth of surface undulations that can be leveled is 4 mm using Polymer Render or 6 mm using PR Hi Build, plus the dry film thickness of any additional textured coating used.
• If further undulations develop in the PVC substrate over time, these will show through to the finished coating system, and are not the fault of the coating system.
• To avoid moisture being trapped in the Polymer Render, it is important that the Polymer Render be allowed to dry to 15% or less Wood Moisture Equivalent through-out its thickness, before application of subsequent coatings. Drying time will be considerably longer on PVC substrates than for other substrates. The Polymer Render will need protection from rain during drying.
• Whatever system is used, it is important to minimize moisture penetration into the Polymer Render & PR Hi Build by finishing the system with either two coats of product from the Armour family or, in some cases as shown in the System Chart, two coats of Clearcote. This is not optional.

May 2008

ROCKCOTE QUICK RENDER - Over Power Panel

 

SURFACE PREPARATION

All surfaces must be clean and free from oil, dust, dirt, silicone, and in particular, loose materials. This is done using a stiff broom.

The power panel should be installed according to the manufacturers written instructions.

JOINT PREPARATION

Ensure joints are filled with thin bed adhesive. If not already filled, fill with this material, or preferably, a mixture of Hebel dust and thin bed adhesive. Fill any holes and/or imperfections and repair any panel damage with same material.

BASE PREPARATION

Priming should only be required in adverse heat and/or windy conditions, this is to prolong the dryingtime and to allow more time to work the product to the desired finish.

Meshing of the vertical panel joint is required when the joint is an external corner (90 or 45 degrees) and not a control joint. In this case, the top hat section is not continuous across the joint and therefore is prone to minor movements and potential cracking.

Meshing is only required across the usual panel joint when the coating used on the wall is not flexible eg. Mineral based products ( Rockcote Quick Render ). In this case 100mm fibreglass tape is recommended.

BASE APPLICATION

Prime if required 50/50 Masonry primer and water. Apply fibreglass tape to joints. Rockcote Quickrender is applied using a stainless steel trowel to an approximate thickness of 4-6mm. As the Quick Render begins to set it is screeded and/or floated to achieve an even finish. This is left to cure for 1-2 days. The surface is now ready to accept acrylic texture or external paint.

The Rockcote System Chart shows the systems specified by Rockcote Enterprises Pty Ltd to achieve texture and other finishes which afford both decoration and protection to the substrate.

It is not uncommon for specifiers and their clients to select products and systems which are highly decorative and/or economical, but do not provide the same degree of long term protection in terms of dirt, mould and water resistance.

For this reason the Rockcote Enterprises Pty Ltd guarantee period is variable, as shown, and in cases where the full specified system is not used, may be considerably reduced or not applicable.

Specifiers and applicators intending to diverge from the systems on the chart should contact Rockcote sales staff for advice.

Certain pigments are not highly colourfast, and coatings manufactured to those colours when used externally may show some degree of fade within the system’s guarantee period. Such fade cannot be covered by any guarantee.

Clients should consult Rockcote sales staff for assistance with final selection of durable colours.

SYSTEM CHARTS following ...

• Bricks & Blocks

• Cement Sheet (Fibro)

• All Lightweight Systems

• Off-form & Tilt-up Panels

• Hebel Power Panel & Blocks

• PVC Blocks (DINCEL)

• Supaboard Panels

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