Drying times of renders varies enormously depending on weather, wind, the substrate being applied over and how thick the render is applied. There is therefore no simple answer to this question. After applying a small section of render to a wall, attempt floating as rapidly as possible before render dries. If the render sticks to your float and or peels off from the wall, it is too wet and not ready for floating. Continue applying render and checking as you go.
Can I render over painted brickwork?
Yes. If the paint is well bound and not flaking, peeling, bubbling etc. The recommended key coat is Unitex Polymer Render as it is a render designed to adhere to difficult substrates such as strongly adhering paint. As always, ensure the surface is dry, clean and free of oils, dust, dirt etc before applying. Test with a sharp knife, using the “Cross-hatch Method” (see Unitex.) If greater than 15% pull off and remove all loose and poorly adhering paint prior to coating.
Why use pre-coated sheets instead of raw polystyrene?
There are several reasons:
1) Immediate protection from the elements. Raw polystyrene, if left un-coated will surface degrade and reduce adhesion of base coat renders, causing possible delamination of renders.
2) The first coat of render applied to polystyrene panels is crucial. This render must have superior adhesion and flexibility than standard renders for brickwork for instance. In the Unitex factory, EPS sheets are transformed into Unitex Base Board sheets by applying alkali resistant fibreglass mesh and a strongly adhering and flexible polymer modified cement coating with a consistent film build with a toothed profile. The special toothed profile makes it easy for the applicator to trowel on the base coat levelling render, (Uni-Dry Cote BBR 8.5 kg), at the recommended film build once the Unitex Base Board sheets have been fixed to the frame, ensuring that only the most flexible render on the market with the greatest adhesion has been applied on your project.
3) Raw polystyrene sheets should not be coated whilst wet as this prevents renders from adhering to the surface. This can cause major delays during winter months. Unitex Baseboard is manufactured inside under controlled conditions.
4) System warranty’s for your peace of mind, Unitex Baseboard is a risk free proven surface.
5) Speed. Unitex Baseboard saves time as the first coat of render is already completed.
What is the lead-time from order to delivery?
Orders within Victoria are generally filled and delivered within 48 hours. NSW and other states (including local Unitex Stockists) are generally within 5 working days.