Frequently Asked Questions

What special precautions are needed when working with Renderoc RSXtra given its very short pot life?

The very short pot life of Renderoc RSXtra (approximately 5 to 10 minutes at 25 degrees Celsius ambient) demands careful preparation and a disciplined working sequence before mixing begins. All preparation work — substrate cleaning and chipping, bonding primer application and tacking, formwork placement, and ready access to mixing and application tools — must be complete before the mortar is mixed. Only the volume of mortar that can be mixed, transported to the repair location, placed, and finished within the pot life should be mixed at one time. In hot Indian summer conditions (35 to 40 degrees Celsius), the pot life is shorter than at the reference temperature — precool the mixing water with ice and work in shaded conditions where possible. In cold conditions (below 10 degrees Celsius), the setting will be slower and the pot life extended. Never add extra water to RSXtra that has started to stiffen — this destroys the structure of the hydrating mortar and produces a weak, non-structural repair.

Can Renderoc RSXtra be used for repairs on a busy highway with traffic closures of only two hours?

Yes. Renderoc RSXtra is specifically designed for exactly this application — repairs on busy roads, national highways, and bridge decks where the traffic management authority allows only short overnight or off-peak closures. With compressive strengths of 15 to 25 MPa achievable within 1 to 2 hours, and full 28-day strength of 60 MPa or above, the repaired area achieves the structural capacity to withstand vehicle loading within the closure window. For a 2-hour repair window on a highway, the typical sequence is: traffic management deployment (15 minutes), substrate preparation (30 minutes), primer application and tack (15 minutes), mortar mixing and placement (10 minutes), finishing (5 minutes), and curing and protection (15 to 25 minutes waiting for early strength before traffic is returned). This tight sequence requires an experienced and well-organised repair crew with all materials and equipment pre-positioned before the closure begins. Space Arc Engineering can supply Renderoc RSXtra for urgent highway and bridge repair requirements across Delhi NCR.

Is Renderoc RSXtra compatible with the full Fosroc Renderoc repair system including bonding primers and protective coatings?

Yes. Renderoc RSXtra is compatible with the Fosroc Renderoc repair system and should be used with the appropriate bonding primer (Nitobond SBR slurry or Nitobond EP epoxy primer depending on the substrate condition and structural requirement) applied to the prepared substrate before the rapid-setting mortar is placed. The primer must be in the correct tacky condition when the RSXtra mortar is applied — on very smooth concrete the Nitobond EP epoxy primer is preferred for its stronger chemical bond, as the short application window with RSXtra makes it important to maximise the initial adhesion. After curing, protective coatings, anti-carbonation paints, and waterproofing systems from the Fosroc range can be applied over the cured RSXtra repair, after allowing adequate curing time (typically 7 to 14 days for the repair mortar to stabilise moisture content before application of coating systems).