A question for the lime experts

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I have an outer wall that I have removed pebble dash from. By removing the pebble dash it has caused some of the bricks to become loose/live even though I was being very careful, all by hand. To solve this problem I am going to rake out the joints and re point in 3.5 medium grit Hydraulic Lime Mortar from a company called Conserv. I am repointing with lime as this is what the house was built with. What I need to know is how long does hydraulic lime/mortar take to set?. I intend to render over the brick work again once repointed but only once the lime has set. Any help here would be appreciated. Thanks Adam
With NHL it could be a day or so before you can render it. But it will carry on setting in the background even if not fully cured. The NHL gives it a hydraulic set so will cure even under water.
If the wall is very dry, it should be dampened thoroughly but not have water running down the wall. This is to prevent the mortar drying out too quickly. If the weather is sunny or windy, the mortar should be protected & prevented from drying out too quickly. Ideally use a garden sprayer to spray a fine mist onto the mortar to keep it damp for a few days. As bodders has stated, the mortar will have an initial set in about a day or so, but "carbonation" continues for quite a while, ie. months. Use the mortar fairly dry, as if it is too wet there may be excessive shrinkage as it dries. About 6-12 hours after placing the mortar,just as it is setting, it should be "beaten" with a churn brush (not rubbed) to consolidate the mortar & heal any small cracks that may have appeared. Have a look on Youtube for some videos. It is probably best to stay away from American videos, as they have a more lax attitude to the use of cement.
Conserve are the best lime suppliers in the UK i use them all the time... pointing with a nhn 3.5 will be fine... leave 5 days before rendering with lime but make sure you that you allow a minimum of 7 days between coats and protect from sun, rain etc.. heres a job i did earlier this year with conserve renders in barbados


Do Conserve do bulk deals? Prices on there website seem pretty high to me.
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