Hydrated lime

[HawkEye244]

Posted here to get more action.

I want to hear from people that have used hydrated lime/sand mix and how long it takes to set? I can't find information anywhere about setting times and shops are closed. Used externally in a foundation.

 

[John D v2.0]

you'll be waiting a long time for an answer, they're still waiting for it to set! you need hydraulic lime not hydrated

 

[wessex101]

Posted here to get more action.

I want to hear from people that have used hydrated lime/sand mix and how long it takes to set? I can't find information anywhere about setting times and shops are closed. Used externally in a foundation.

Rather a confusing question. You would usually add hydrated lime to a sand/cement mortar mix not use it for a foundation, in that case it sets slightly slower than ordinary sand/cement mortar. If you have just used hydrated lime and sand it will never set just dry out.

 

[HawkEye244]

Pity, I took advice from a friend and when I checked my local merchants they stocked just the hydrated lime so I bought that without thinking. It's just hydrated lime and sharp sand mix so yes a costly mistake.

I can't use Portland cement in the mix because of politics on site, it's for an allotment.

 

[John D v2.0]

Hydraulic lime is a specialist material so not available everywhere. Hydrated lime would set by absorbing co2 from the air when dried out, but for a foundation that won't happen. I guess that's not the kind of action you were hoping to get!

 

[Ian H]

Have you considered spraying it with glyphosate to speed up the curing process?

 

[HawkEye244]

Hydraulic lime is a specialist material so not available everywhere. Hydrated lime would set by absorbing co2 from the air when dried out, but for a foundation that won't happen. I guess that's not the kind of action you were hoping to get!

Hmmm, except the foundation isn't backfilled. So perhaps leaving it for a week or so covered with tarp is enough time to let it set. Obviously it's the best of a bad situation.

 

[JohnD]

IIRC Buckingham Palace was built with a lime oversite, and if you go into the undercroft you can still pick pebbles out of it with your fingers.

 

[HawkEye244]

Well double checked again and my friend used hydrated lime and cement in his foundation, checked it and it's set, although you can rake at the joints with your fingers.

I haven't filled the joints yet and when I do I'll add cement to the mix, enough to be undetectable. It's enough to get the greenhouse up if only for one season.