lime or cement mortar?

Until I watched Countryfile on Sunday and heard John Craven talking with a company in Wales who make lime mortar and run courses etc., I was going to repoint my 150 year old end terrace with cement. I think I have lime mortar since it's a magnolia/yellowy colour.
I need to repoint inside and outside. Inside the plaster has blown and the mortar is very crumbly. Was planning to
rake out old mortar cover wall with cement render, pushing render into the joints cover with insulated plasterboard.
If I need to avoid cement where can I get lime mortar.
Thank you,
Neil
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You mix your own with cement and lime and sand. The proportions will depend a bit on the sort of wall and property you're dealing with.
One suitable mix might be 1 lime, 2 cement, 9 sand by volume. Brickies might dispute this, or have other ideas.
Rob Graham
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I'd agree with what Jacob has said, if it was lime mortar originally avoid putting in cement it will cause more problems that it will cure. The same goes for lime based rendering, replace like with like and don't be tempted into a cement based stronger mix.
--
David

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Niel A. Farrow wrote:

You can buy hydrated lime at any builders merchant.
I actually have used a mix with about 4 sand to one cement and one lime.
Its proably completely wrong :)

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