Hi guys need a bit of help guessing how much sand/cement I would need to render a 100m2 wall at 25mm/20mm thickness? Any help would be great. Cheers

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10 bags of cement to a sack of sand which are not full ton sacks these days,assuming background is reasonably flat. you can always grab a couple more cement if needed .
 
Why ever dont you use OCR ? It will give you the correct mix, a uniform colour, the sand in OCR is a lot better quality for rendering the the builders merchants plastering sand which is way too soft.
 
20 to 25 mm thick , this is way too thick. Have you ever carried out any rendering before?
Gravity Doc GIF by Back to the Future Trilogy
 
yes using sand and cement, here in Belfast its common to go on at 20mm possible due to the severe weather or something I'm not too sure?
 
Why ever dont you use OCR ? It will give you the correct mix, a uniform colour, the sand in OCR is a lot better quality for rendering the the builders merchants plastering sand which is way too soft.
have been looking into this stuff, looks amazing. More like plaster by the looks of it, its just trying to convince the customer its worth the money.
 
You tell him, don’t stand for any of his nonsense!
mate I have rendered before so I know what I'm doing with that side of things, just that I always had a mix waiting for me on site so never had to worry about the calculations of the mixing. So soz if I sound like a spanner I just want to be safe.. I know the coats go on at different thicknesses, was just double checking the calculations are about rite as I've never had to deal with that side of things. I know it sounds stupid but f**k it need to find out somewhere.
 
30 cement, 4 800kg bags sand at 5/1, at 20 mil for 100 m.
Might have a couple of shovels left over
 
Ffs, it’s just simple maths.
Are the majority of spread’s on here really that brain dead?
 
Finished rendering a 2 bed bungalow recently. 3 sides. Used 2 ton bags of sandgate sand . And 12 bags of dust . 2 bags of lime. 10mm angle. And stop beads. 15mm bell cast. Painted the front only.
 

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Finished rendering a 2 bed bungalow recently. 3 sides. Used 2 ton bags of sandgate sand . And 12 bags of dust . 2 bags of lime. 10mm angle. And stop beads. 15mm bell cast. Painted the front only.
Do you take on the painting on your own renders?
We've been doing it for the last few years.
 
If you think it takes the same amount of cement on each coat perhaps you should be leaving it to someone who knows what they're doing mate.

Andy there are many bagged renders you can 2 coat with...do you buy a different bag with a different amount of cement for each coat...no.

As long as the top coat is not stronger than the scratch coat the coats can be of equal strength.

It's bullsh*t the top coat has to be weaker than the scratch.

I've done probably 50 houses with 4.1 - 4.1.1 and never had any problems...and I've used 1000's of bags of KI7 scratch and top never had any probs.
 
Andy there are many bagged renders you can 2 coat with...do you buy a different bag with a different amount of cement for each coat...no.

As long as the top coat is not stronger than the scratch coat the coats can be of equal strength.

It's bullsh*t the top coat has to be weaker than the scratch.

I've done probably 50 houses with 4.1 - 4.1.1 and never had any problems...and I've used 1000's of bags of KI7 scratch and top never had any probs.
The saying “ it shouldn’t be stronger than what your going on to” has been interpreted that it should be weaker
 
Andy there are many bagged renders you can 2 coat with...do you buy a different bag with a different amount of cement for each coat...no.

As long as the top coat is not stronger than the scratch coat the coats can be of equal strength.

It's bullsh*t the top coat has to be weaker than the scratch.

I've done probably 50 houses with 4.1 - 4.1.1 and never had any problems...and I've used 1000's of bags of KI7 scratch and top never had any probs.
You're f**k**g clueless
 
Basically @essexandy is wrong. The top coat does not HAVE to be weaker than the scratch coat, it can be of equal strength but not stronger.

He won't admit it though to stubborn
 
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