Ready-Mix Spray Plasters are a rapid, cost-effective alternative to traditional (manually mixed & manually applied) plaster for finishing external & internals walls and ceilings. They are formulated for machine application on fast-track & quality building projects. They are supplied as “dry pre-mixed” to the correct consistency for spray application by Plaster Machines.
Ready-Mix Spray plastering has been used in Europe, UK, Far-East for many years and is quickly becoming a widespread alternative to traditional plastering due to both it’s economic benefits and rapid speed of application.
What are the Major differences between Traditional On-Site Plaster Vs Ready-Mix Plaster vs. Ready-Mix Spray Plaster?
Traditional On-Site Plaster
Ready-Mix Spray Plaster
6-10 minutes before applying
Mixing time with water approx. 3-6 seconds before applying.
Retarders slow down the setting time and generally make the mixture more workable.
Modern plasters come already mixed with perlite, vermiculite and several other additives.
These additives provide a greater degree of insulation and fire resistance.
Application by UELZENER ReadyMix Spray Plastering Machine (Mixing-Pumping-ConveyingSpraying) – It has a mixing pump
(rotor-stator). Dry pre-mixed material is fed into the hopper and is transported into the mixing chamber.
A constant supply of water, adjustable according to the mixture required, is fed into the chamber to produce a continuous consistent mix.
The mixing shaft transforms the dry powder into smooth wet plaster, render, mortar, grout or floor screed in seconds, also drives a pump which conveys the always fresh mixture to the work area.
The plaster mixture is very sensitive to variations in water content.
The skill of the plasterer is not just in the finishing but in the gauging the wetness of the mixture to be applied.
Plasterer adds more water for ease of application.
The plaster mixture is sensitive to variations in water content.
There are quite a few plasters but two main types: Gypsum-based: They are used indoors only, damp will attack a gypsum based plaster and cause it to crumble. Cement-based: They are used mainly for outdoors, generally for rendering. Cement based plasters can be used indoors for areas that are susceptible to damp and areas that require a greater thickness of cover.
Normally Ready-Mix Plasters are available in three finishes: Standard smooth Finish – After spray plastering Base & Finish costs, the plaster is then manually smoothed over with large spatulas or butterfly trowels to give a smooth hard wearing finish
Fine Textured – After spray plastering Base & Finish costs, the spray may be left to give a “textured” finish. Course Textured – After spray plastering Base & Finish costs, the spray may be troweled to give a “textured” finish. For the texture finishes a hard wearing, water resistant material is used which does not need final decoration; ideal for high traffic areas such as stairwells and corridors.
Normally 2 product ranges: Base Plaster: Filler and levelling compound for use over thin joint brick / block systems, uneven in-situ concrete and on refurbishment projects to fill cracks, holes and undulations to prepare surface for final decoration. Normally applied upto 5-10 mm (max. 20 mm) thick in one application. 1 to 2 coats are recommended with 12-24 hrs drying between applications. This is applied using Uelzener Ready-Mix Plaster Machines. Finish Plaster: Normally applied upto 1-2 mm thick as a single top coat on “Base Plaster” or as a 2 coat finish directly onto smooth backgrounds including pre-cast panels, Aircrete panels, composite boards, and/or refurbishment over previously decorated surfaces. This is applied using Uelzener Ready-Mix Plaster Machines.
Base Plaster: Normally 1.5–2.0 Kg per m2 at 1 mm thickness Finish Plaster: Normally 1.35-1.5 Kg per m2
Ready mix plaster can be applied to almost any substrate including brick work, block work, concrete panels, dry lining, plaster boards, ceramic tiling, artex, wood, glass, steel, old / damaged plaster, and even painted wall coverings (e.g. woodchip).
Why should you use Ready-Mix Spray rather than “traditional on-site” plastering? What are the benefits of “Ready-Mix Spray Plaster” using UELZENER German Spray Plastering Machines?
It absorbs and subsequently releases moisture (5-10% of its own weight in water) greatly reducing the incidence of condensation and mould growth.
Can be applied by the same teams applying paint finishes
Speed & Cost…
The use of ready mix plastering over traditional plastering techniques offers significant savings during the project by significantly reducing construction time by optimizing internal fit-out. It’s fast! A two man team can cover between 200 and 500 m2 per day (typically 2-4 times faster than traditional plastering techniques) depending on the substrate. Upto 1,000 m2 per week can be finished by a three man gang.
* Surfaces can be emulsion painted 24-48 hrs after final coat (saving project time and cost).
* White surface finish reducing paint coats required (saving project time and cost). * Material can be tinted the same colour as the decoration reducing maintenance requirements over a long period (saving project time and cost). * Ease of Access: Heights of upto 3.0-3.5 meters can be plastered without the need for scaffolding or platforms, although brick/block work & surface preparation may require scaffolding (Health and Safety).
Hardness = range of 10 N/ mm²
Tensile Strength = range of 1.8 N/ mm²
Compressive Strength = 2.2 to 5.5 N/ mm²
Flexural Strength = 1.8 N/mm²
Bond Strength = 0.33 N/mm²
Pull-off adhesion Strength = 0.35 N/mm²
Impact Strength = 4.5 mm
The key benefit of mixing and pumping plastering machines to architects is that of consistent quality, helping to ensure that colour and finish are as envisaged at the design stage. Architects and specifiers also have the facility to select modern materials such as fast flowing, fast drying, self levelling floor screeds and other liquid mortars with the benefit of greater performance, physical properties relevant to their location and reduced drying times.
For the contractor the key benefit is also that of higher consistent quality, resulting in lesser correction, no hacking off and so reducing the likelihood of rectification costs. Costs are further reduced as construction can proceed more quickly and importantly there is less risk of damage to materials on site. Other advantages to the contractor include early removal of scaffolding, less waste on site and low maintenance cost. But the key benefit is that using a machine enables an accurate account of the material used.