# Forum Home Renovation Brickwork  Masonry Block - Mortar Mix

## scoobysteve

Hi All, 
i've been reading through the previous posts about mortar mixes as well as the mortar guide on the boral masonry block guide and it has left me confused. 
on the boral guide it indicates to NOT use brickies loam/sand on the masonry block as the brickies sand contains clay. Because of expansion of clay with heat, the clay bricks work well with the brickies sand however because the blocks are concrete it doesnt. the boral guide indicates to use pit sand (washed sand?) instead. 
Now, reading through another post, another member had problems trying to get his mortar mix of cement, washed sand and lime to stick to the block and he also indicated that the mortar was almost impossible to work with (hardened quickly). With the advice of other members which was to use brickies sand, he ended up using brickies sand and it was so much easier to work with. 
Now, do i use brickies sand? or the pit sand as per the boral guide? Lime as well?  
Lastly, i think the ratio is 1:1:6 (cement, lime, sand). Please correct me if i'm wrong. 
any suggestions much appreciated. thank you.

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## rrobor

It depends on the sand, and each sand differs. I hail from an area in Scotland which has the best sand, They carted that from Central Scotland to SE England to build a bridge. So no one here can give you the definative answer, you have to feel and see the stuff. Your mix is 7 to 1, thats a bit weak for me. I would use a washed sand with lime but not a concrete sharp sand.

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## intertd6

If your laying 200 series blocks then sharp (washed) sand is a must, even with that you will have to hold the blocks weight for a few seconds, untill the block sucks the moisture form the mortar making it stiff enough to hold the blocks weight, with brickies sand the mortar will just slump & not hold the block up to your line.
regards inter

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## scoobysteve

hi  
intertd6, you've said that i must used washed sand and hold the blocks for a few secs so the mortar can hardened up - does this mean that i shouldnt use lime in my mortar mix as i guess the lime with soften up the mix?

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## GrahamC

I'm using boral 190mm designer block. When I rang up i was refered to techdry as the recommended addative - it is meant to make the mortar water resistant - and it seems to. It is also a pasticiser which made the block layers complained about. The 16kg blocks just had a tendancy to sink into the mortar. 
I noticed that when I was washing down the walls, the block would darken as they got wet, but the mortar would just stay the same colour. 
Being for a retaining wall, the mortar mix was 4:1  (M4)

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## scoobysteve

hi all, 
just found out that the brother of a work colleague is a blocklayer who's been laying in this area for 20yrs. my work mate has also had a masonry block retaining wall done a few years ago and he said that they used brickies sand - not the pit sand as per the boral guides. 
Thats probably what the majority uses as nearly all houses here are masonry block then rendered yet all landscaping/raw materials places here stock brickies sand/loam. i guess if brickies sand wasnt suitable then the raw materials places wouldnt stock it as the blocklayers wouldnt use it. 
well i think i'm gonna stick to brickies sand/loam with cement on a 1:4 mix - no lime.

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## intertd6

> hi all, 
> just found out that the brother of a work colleague is a blocklayer who's been laying in this area for 20yrs. my work mate has also had a masonry block retaining wall done a few years ago and he said that they used brickies sand - not the pit sand as per the boral guides. 
> Thats probably what the majority uses as nearly all houses here are masonry block then rendered yet all landscaping/raw materials places here stock brickies sand/loam. i guess if brickies sand wasnt suitable then the raw materials places wouldnt stock it as the blocklayers wouldnt use it. 
> well i think i'm gonna stick to brickies sand/loam with cement on a 1:4 mix - no lime.

  Just check to see what tricks they use to make it work & seeing your doing it your self you will need those to make it easier. Generally sharp sand is used for blocklaying, rendering & concrete.
regards inter

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## rrobor

Just be very careful about making your mix too strong and not using lime. If you do make that what you create is a very brittle wall and if its big enough it will crack. Also a spot of detergent in the mix (wash up liquid) keeps the mix in good shape for longer.

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## scoobysteve

Hi Guys, 
I'm almosted tempted to use lime as well - a lot of other post indicate to use lime as well. 
I've attached a pic of the boral mortar guide - I'm going to either use the 1:4 (cement, sand) or the 1:1:6 (ement,lime,sand) mix. 
saying that, if i use the 1:1:6 mix, why does it say that for 1m3 of mortar, i'll need 14 bags of cement, 5 bags of lime and 1.2m3 of sand. Shouldnt it read 14 bag of lime as well if it is a 1:1:6 mix? 
let me know your thoughts.

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## scoobysteve

hi all, 
i ducked by bunnings to pick up some GP cement and asked the guys there.. the bloke who worked in the respective area said that for about 50 bags of GP cement he sells, 1 bag of lime was sold... so i guess a 1:4 mix must be used as a majority up here. 
thanks for all you're help. 
i will give pics of my wall when it done...

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## an3_bolt

> saying that, if i use the 1:1:6 mix, why does it say that for 1m3 of mortar, i'll need 14 bags of cement, 5 bags of lime and 1.2m3 of sand. Shouldnt it read 14 bag of lime as well if it is a 1:1:6 mix?

  Perhaps it could be a mix by volume and not weight? :2thumbsup:

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## scoobysteve

I also thought as well (mix by volume).. i'm assuming that in 1m3, 12 bags of cement, 5 bags of lime and 1.2m3 (allowance of excess) of sand will make 1 cubic metre of mortar. 
however saying that, i've found elsewhere on the net where they've listed 1:1:6 and the amount of lime is equal to that of cement. ie, if i buy 12 bags of cement, i also need to buy 12 bags of lime. 
anyhow, i've started laying today with a 1:4 mix and it's not too bad. the mortar tends to not stick greatly however if it is a bit more slushy as opposed to dry then it does. if i hold the mortar onto the block for a sec or two, then the mortar is happy to stay but straight off the trowel, it doesnt.

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## autogenous

4 buckets sand (washed, brickies, what ever), 1 bucket GP, half a bucket of lime. 
Mix it so it is like gelato ice cream. 
[ame="http://www.youtube.com/watch?v=8VGjA66RSm0"]YouTube - Brick Laying and Masonry[/ame]

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## scoobysteve

hi guys,  
after about 7-8 barrows of mortar, i now make "alright" mortar. the mortar is sticky and easy to spread. however, because the blocks are so heavy (supposedly 16kgs each), the block simply just squishes out the mortar. If i make the mortar slightly "drier" then the mortar is harder to lay and it doesnt stick too well also. 
I'm amazed how easily the mortar comes off the trowel and then how well the block sits ... it just doesnt sink any more.

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## sundancewfs

I used to try mixing motar in my cement mixer..... what a nightmare! 
I now use a 25litre mortar bucket with a large mixing spiral on my cordless drill and a baby formula tin as my measure.
Smaller batches, much easier to manage, easier to get to the right consistency, great if I suddenly have to stop, (rain, kids, etc) as I don't lose too much mortar and eaiser to clean up :2thumbsup:

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## GrahamC

I watched the video, the guy either must be very strong or have very light blocks.

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## scoobysteve

those blocks definitely look heavy... 
Anyhow, slightly off topic, i'm intending to get a concrete truck in for my core-filling however, just wondering what the best way would be to get the core-fill into the blocks? i can go buckets but it will be a million bucket loads, not only that, the time it will take will be long and it will be expensive as the truckie would have to charge for the extra time. 
the reason why i'm intending to go using the trucks is that each bag of concrete is about $8/ 20kg bag and you need about 300kgs of cement per cubic metre. I need 2 cubic metres (200 H blocks). At that price, the price of a truck i believe would only be a bit more - well worth the extra if you take into consideration the labour and inconsistencies involved in mixing it yourself. 
Anyhow, i thought that i could use a decent plank of wood behind the blockwork and have the concrete truck have its shutes aim for the holes using the wood as a backboard - the only problem i see here is the weight of the concrete that would be pushing against the board.  
anyone with any ideas or suggestions on the above mentioned method as well as any methods would be great.

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## Bros

> At that price, the price of a truck i believe would only be a bit more - well worth the extra if you take into consideration the labour and inconsistencies involved in mixing it yourself.

  Smart idea as getting a truck is much better. With concrete trucks make sure you have more people than you think and more wheelbarrows as they won't charge extra time if you are making an effort to turn the truck around as soon as possible ( well that's my experience and also coming from a mate who owns a concrete truck). And as you are in NQ something to satisify their thirst. 
Make sure you tell them it is for blockfilling as they will only put in smaller aggregate. 
I had a big wall to do for a shed and I got a pump and they supplied a person to fill the blocks but as yours is small I have seen the pro's with a longish funnel about 1.5 m long made from two planks fixed together that they slide along the top of the blocks. If you have a couple of mates with leather gloves they can push it into the holes by hand or use a spade or if you can get behind the wall a piece of ply directing it into the holes. The truck doesn't just pour it out in an endless stream and it can be controlled to your speed but as you would have got a truck for the foundations you would be experienced with that. 
The easiest part with concreting is watching someone else doing it.

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## GrahamC

You could go for a treme mix (very high slump) to make it down easier. When I first core filled, I went for a 230 mm slump 25mpa 10mm agregate. You can also wet down the cores to make it flow easier. It is also worth it to have a length of Y12 to shove down the cores to make sure the mix is going to the bottom. 
You also might get the truck driver to dump the spare mix into a wheel barrow before he leaves just in case you find a few cores not filled after he leaves.

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## scoobysteve

hi guys, 
thanks for the advice.. 
i like the funnel idea and it will stop spillage on the face side if the concrete doesnt somehow go down the holes..  
Also, thanks for the advice on the slump type etc.. i was just going to ask for core-fill and hopefully they've got something to suit. 
Lastly, I remembered i got a large 2nd hand plastic pool which was meant for my daughter. I could use that for temporary storage if time runs out - plus i will still have 2 wheelbarrows as well. Just not sure if it would hold. 
anyhow, thanks again. will keep you all posted.

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