Resin bond infill layer

[Nik]

Easter greetings all,

I'm currently undertaking a garden paving job that is 85 sq mtrs of squares created with 600x70x30mm dressed granite 'strips' infilled with Ronacrete Resin Bond aggregate. I will have a freshly prepared concrete slab upon which the granite will be mortar layed upon.

Here's the snag, even with only a 10mm mortar bed, I'm left with just shy of 40mm depth per square (ea 0.36 sq mtrs) to build up to a height suitable for surfacing (to flush with granite).

My first thought is to screed each square to required depth, has anyone experience of anything similar? My main concern is seraration of the screed layer / resin bond should I get any water ingress. The total amount needed is in the region of 1.5 cubic metres of infill.

Any thoughts / recommendations glady received,

Nik..

[Tony McC]

I'd use a 4:1 mix of grit sand with cement, bonded to the concrete base. If the resin is properly applied, there shouldn;t be a problem with water ingress, but I'm sure Sim would be able to better advise you.

[Nik]

Thanks Tony,

Much as I had in mind then, screed and plenty of PVA it is then unless Sim says otherwise!

Nik..

[simeonronacrete]

PVA! Ahhhhhhhhhh!!! No, not outside. PVA will break down.

4:1 sharp sand : cement is OK.
Instead of using just water to gauge the mortar, use a mix of 1:1 Ronafix:water. Dilute the Ronafix (a white liquid) with clean water 1:1 and enough to the cement and sand to make it to a screed consistency (semi-dry). Trowel this on to the base.

Before you lay your screed, prep the concrete underneath to remove dust, dirt, oil, grease, moss, all the usual nasties, and at the very least give it a good wire brush (ideally mechanically abrade it). Wash with water, remove ponding water, then prime it.

The primer is 1:1 Ronafix : cement (no water), made into a runny slurry. Brush this onto the damp concrete and lay the screed onto the wet primer. Only prime an area which can be covered with screed before the primer dries - about 30 mins in today's sunshine.

Min. depth for the screed is 6mm, max. 50mm in one layer, otherwise it's too deep to compact.

When you've laid the screed, cover it with tight fitting polythene for a few days until well cured and hard. If the screed is laid too wet you'll create laitence (basically a fine film of cement powder which will then go dusty). You don't want this, because the Ronadeck Fast Grip Resin won't bond well.

When you lay the Fast Grip protect the edges of the slabs with masking tape, otherwise you'll spoil the marble. Remember to remove the tape before the resin sets, or you'll never get it up.

Remember Fast Grip is 1. Fast and 2. a specialist product, so read up and be prepared!

For data sheets on Ronafix go to our new web site at Ronacrete For Flooring. Type Ronafix into the search box and click on the relevant IS or TDS.

Good luck!