RonaScreed SBR is an SBR admixture for site batched polymer screeds and fine concretes, mixed with cement, medium grade sharp sand and, where the mix design calls for it, aggregate. It lays new screeds and toppings as thin as 10 mm bonded, or 35 mm unbonded and floating. Bonded screeds are primed with a RonaScreed SBR and cement slurry for monolithic adhesion to properly prepared concrete or screeds.

Key Benefits

Application

Mix 1: 50 kg CEM II 42.5 cement, 200 kg 0/4 mm screeding sand and 10 litres RonaScreed SBR, plus water to a consistency where a squeezed ball holds together without free liquid (yield 0.12 m³). Mix 2 uses 5 litres of RonaScreed SBR; Mix 3 replaces 50 kg of the sand with 3–6 mm granite. Do not pre-dilute, and do not use a semi-dry mix. Mix for 2–3 minutes, ideally in a forced action mixer. For bonded screeds, the base should be dry (below 75% RH) with an effective DPM; prepare by shot blasting, planing or scabbling, wet thoroughly, then brush on a 1:1 (by volume) RonaScreed SBR and cement primer and lay onto the wet primer. Lay over 50 mm wet on wet in more than one layer. Cure with Ronacrete Curing Membrane, or polythene for at least 24 hours. Check the manufacturer's datasheet before use.

Coverage

Mix 1 and Mix 3 use 10 litres per 0.12 m³ batch (roughly 2.4 m² at 50 mm); Mix 2 uses 5 litres. As a primer, 1 litre of RonaScreed SBR mixed with cement covers approx. 3–4 m².