Advice on rendering front of 1930 house

[Spectrum2260]

Hi
I am attempting to restore a 1930 house. I have taken off all the pebble dashed render off the front of the house back to brick, as it was blown. I have discovered that the scratch coat is a thin 5mm dark hard cement and the pebble dash coat was lime based top coat. Iv tested the lime pebble dash and with vinegar and it reacts confirming it is lime, where the scratch coat does not react.

when I re-do the scratch coat, should it be a cement and lime (hydraulic) mix?
I don't want to do lime only and sand scratch coat, as I have read lime will not stick to wall that has remnants of cement on it.

Thanks

 

[vards01]

I'd take a look at parex parinter its a lime based base coat for renovation projects. It is expensive, but worked very well for me, I used it on my 1890's property and it adhered very well to old bricks / lime mortar, whilst maintaining the breath-ability of the building. I did also use a product called monogrobtis which is an exterior bonding agent. I top coated with monocouche coloured render (no more painting).

You can also bed a fiberglass mesh in which minimizes the risk of future cracking.

 

[Happyplumber]

Do you have a wel insulated building ?May be an idea to look into external wall insulation if you are thinking of rendering the property anyway