Calculating sand for internal cement render

[Poe]

I've just taken one of our bedroom walls back to brick.
The walls are quite uneven but was wondering if there is a rough guide to calculating how much materials I need.
Don't want to get in a bulk bag of plastering sand if I can help it.
Cheers

 

[ree]

OP,
The modern practice for your purpose is to use a 3:1 mix of sand & NH lime.
No need for bulk. You can buy bags of pre-bagged sand, and a bag of NH lime powder all separately.

 

[Poe]

I'll take a look at lime plaster.
I was hoping to use 25kg bags of plastering sand just depends on the amount I require and cost Vs a bulk bag.
How do you normal work out the required amount?
Thanks

 

[ree]

OP,
Its lime render not plaster. Render goes on in two 10mm coats & a cementitious skim finish.
How can I say what amount you need - I dont know the dimensions or the state of the bare brickwork?
Buy enough sand for one coat. The lime comes in 25kg bags.
Get the scratch coat on the wall - scarify it - leave it for 24hrs.
Now you know how much you will need for the second coat

 

[Poe]

Yes I meant lime render.

I never asked you to tell me how much materials I would need.
I asked for someone to tell me how to calculate the amount that's required fir myself.
Looking around on the web and forums sand and cement seems more widely used sometimes with a small amount of lime added for workability and breathability.
Couldn't see many using just lime and sand.

 

[Alastairreid]

Render Calculator, Estimates for Lime Rendering

Estimate quantity for lime render with a three coat system. This calculator will tell you how much render you need in kilograms from the wall area or dimensions.

www.lime-mortars.co.uk