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cumface

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Mixing render for garden wall and side and back wall of garage.

3:1 scratch coat with waterproofer setting 1 coat beads on corners of garage,doorway and piers.10mm thick

4:1 render coat with waterproofer. Put on wall at 10mm thick, straighten with wooden straight edge and filling low spots. Rubbing up with float and sponge off after float.

I laboured for my father in law for 1 year and this is how he done it. I'm going to follow what he did but is this right. I can't afford a plasterer, I'm out of work on sick leave and already have materials in so going to attempt it myself.
 
I see on other thread you are sticking beads also. How I would go about it would be , scud first, 2/1 no aditives on wet wall, scratch 3/1 + WP day or so latter again on wet wall, and then just sit my beads upon the scratch coat, on piers make sure plumb in both planes. Following day finnish with 4/1/1 i+WP, being a DIY would suggest hard internal angles/returns. Don't worry too much about depth of coat as you must plumb beads and this will dictate the coat.

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Spunkface that's the ratio we use butmain renderers on here say 5-1 top coat to prevent cracking we have always used 3-1 scratch,4-1 top but mite use 5-1 top coat oursens nxt time
 
Spunkface that's the ratio we use butmain renderers on here say 5-1 top coat to prevent cracking we have always used 3-1 scratch,4-1 top but mite use 5-1 top coat oursens nxt time


5:1 seems very weak. I know and knew a few plasterers and they never spoke of a 5:1 mix. Always 3:1 or 4:1. They always said that your next coat always had to be just that bit weaker.
 
I see on other thread you are sticking beads also. How I would go about it would be , scud first, 2/1 no aditives on wet wall, scratch 3/1 + WP day or so latter again on wet wall, and then just sit my beads upon the scratch coat, on piers make sure plumb in both planes. Following day finnish with 4/1/1 i+WP, being a DIY would suggest hard internal angles/returns. Don't worry too much about depth of coat as you must plumb beads and this will dictate the coat.

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4:1:1 ?

Hard internal angle\returns ?
 
4sand/1cement/1lime

Internal corners= where two walls meet normally at 90°

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I know what the angles are but why did he say 'hard' internal angles.

Why lime on piers and not the wall
 
4sand/1cement/1lime

Internal corners= where two walls meet normally at 90°

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A 4:1:1 mix of sand,lime,cement, when making up a mix like this if used on the whole wall, does adding that much lime not make it dry quicker? Why I'm asking is I remember 2 old time plasterers arguing over that type of mix and one mentioned about it drying quicker. He just wanted 1 shovel in the small mixer rather than a 4:1:1 mix.
 
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But is it not needed for the garage wall. What is it you don't like about it.

I find it makes the mix weaker. And not as nice to float up. And when I have to use it I would not put it in the scratch. Waterproofer is not even waterproof so why even use it.
 
A 4:1:1 mix of sand,lime,cement, when making up a mix like this if used on the whole wall, does adding that much lime not make it dry quicker? Why I'm asking is I remember 2 old time plasterers arguing over that type of mix and one mentioned about it drying quicker. He just wanted 1 shovel in the small mixer rather than a 4:1:1 mix.
Why would it dry quicker?

Waterproof is added pro rata with cement, the stronger the gear the more waterproof it will handle, I apply it directly to the mix roughly a Cork full for every shovel mix of finnish more in scratch. Depends on brands also.

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I wouldn't put lime in scratch coat only top coat cos that will suck it in harder than a Russian brass if u use lime maybe a splash of water proofer just get it moving when I worked on German embassy with proper restorers they never use water proofer and some of these bloke were proper old school one was that old I'm sure Jesus laboured for him
 
5:1 seems very weak. I know and knew a few plasterers and they never spoke of a 5:1 mix. Always 3:1 or 4:1. They always said that your next coat always had to be just that bit weaker.
I know I've always used 3-1 and 4-1 but few renderers on here said that's 2 strong but hey ho just crack on..or bang sum pics on aswell wen finished
 
Mixing render for garden wall and side and back wall of garage.

3:1 scratch coat with waterproofer setting 1 coat beads on corners of garage,doorway and piers.10mm thick

4:1 render coat with waterproofer. Put on wall at 10mm thick, straighten with wooden straight edge and filling low spots. Rubbing up with float and sponge off after float.

I laboured for my father in law for 1 year and this is how he done it. I'm going to follow what he did but is this right. I can't afford a plasterer, I'm out of work on sick leave and already have materials in so going to attempt it myself.



I've worked with plasterers whove stated 3:1 scratch coat, 3:1 final coat. Done a days work for a guy who was even doing a 2:1 both coats, looks lovely when dried out but looking at some of his other work few years after applied, it had spiderweb cracking all over it! Looked awful.

We use a 3:1 scratch and 4:1 final coat like in your OP above. Nothing wring with that and its been the norm anyone I've worked with as well. As for both 10mm coats. I was always told when younger that the scratch coat is the most important and that's to be 12.5 mm and final coat is 8mm. I stick to my own method, if both coats are thick enough not to slide off, its good enough lol. Who in the name of good fcuk gets the measuring tape out and measures it anyway!

When scratching it, make sure to scratch it properly. DONT scratch through the coat onto the block work. Just enough to give yourself a grip for next coat. There's 2 scratchers you can use, a proper one like I use that's like a hair comb or another one that leaves it like a tile trowel finish. I have seen the latter used but never used one myself. Think its more a UK thing.
 
Waterproofer in the scratchcoat only. Not the top coat. If you put waterproofer in the top coat water can get in some places and get trapped. Then the frost comes and.... U know the rest
 
Mixing render for garden wall and side and back wall of garage.

3:1 scratch coat with waterproofer setting 1 coat beads on corners of garage,doorway and piers.10mm thick

4:1 render coat with waterproofer. Put on wall at 10mm thick, straighten with wooden straight edge and filling low spots. Rubbing up with float and sponge off after float.

I laboured for my father in law for 1 year and this is how he done it. I'm going to follow what he did but is this right. I can't afford a plasterer, I'm out of work on sick leave and already have materials in so going to attempt it myself.
This mix is too strong and will crack after a few years.
The stronger the mix the more chance it will crack
I do tons of render with sand & cement and use 5/1
6/1 for float coat
 
Why would it dry quicker?

Waterproof is added pro rata with cement, the stronger the gear the more waterproof it will handle, I apply it directly to the mix roughly a Cork full for every shovel mix of finnish more in scratch. Depends on brands also.

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A cork full! A guy i used to work with used to do a cap full per bag. I stick to what it says on back of container until told otherwise if working for someone else. I Usually do a small coke bottle full(with top slope cut of bottle) to a builders bucket. Has never failed me yet.
 
Waterproofer in the scratchcoat only. Not the top coat. If you put waterproofer in the top coat water can get in some places and get trapped. Then the frost comes and.... U know the rest
Why and how can water get in.
3/4 coats of weather shield ain't letting any water in
 
scud/slurry 5:1 scratch 6:1:1 float coat waterproofer couple of caps per mixer full in both , did lots in Ireland when training up and they were the dogs b*ll***s at it that's all they did day in day out .

All ways done same no problems ever
 
A cork full! A guy i used to work with used to do a cap full per bag. I stick to what it says on back of container until told otherwise if working for someone else. I Usually do a small coke bottle full(with top slope cut of bottle) to a builders bucket. Has never failed me yet.
Yeah that would be about same as I use, I meant about a Cork per shovel of cement. On the container the ratio is given per unit of water , this I find does not work. Have used without in past but throwing on big gables solo soon changed my mind,

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This mix is too strong and will crack after a few years.
The stronger the mix the more chance it will crack
I do tons of render with sand & cement and use 5/1
6/1 for float coat
I changed to a 5-1 and 6-1 recently and did find it rubbed up well and it's still on wall and ain't cracked I go past the house every day so might even stick with it now was taught always do a weaker top coat
 
scud/slurry 5:1 scratch 6:1:1 float coat waterproofer couple of caps per mixer full in both , did lots in Ireland when training up and they were the dogs b*ll***s at it that's all they did day in day out .

All ways done same no problems ever
Scud/slurry 5:1. You sure?

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Scud/slurry 5:1. You sure?

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yeah on the odd occasion 4 and half to 1 but yeah everything around Co. Cork was render these lad been doing it 40 years when i started with them so thought that was all ways the way and its worked for me and others .
 
Am typing this from Co Cork, and if I scudded a house at five to one would not expect it to be still there five years on, I would be amazed if they were doing so, have been on a trowell since fifteen and will be 48 next year.

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Scud, something we don't do unless asked to. Its hasn't failed us yet. Floated a big set of apartments and housing estate 20 years ago along with my house 15 years ago without scud and not one problem. Yes its better to use it but not majorly important if left out IMO.
 
I changed to a 5-1 and 6-1 recently and did find it rubbed up well and it's still on wall and ain't cracked I go past the house every day so might even stick with it now was taught always do a weaker top coat


Will have to try it out on any small areas sometime. If it is good, it'll be good for mother nature having to make less cement for me now :birra:
 
Scud, something we don't do unless asked to. Its hasn't failed us yet. Floated a big set of apartments and housing estate 20 years ago along with my house 15 years ago without scud and not one problem. Yes its better to use it but not majorly important if left out IMO.
Only ever done scud in Ireland in UK meant to rake joint so should be no need for the scud but I never had problems with no scud either
 
Scud, something we don't do unless asked to. Its hasn't failed us yet. Floated a big set of apartments and housing estate 20 years ago along with my house 15 years ago without scud and not one problem. Yes its better to use it but not majorly important if left out IMO.
Great sand in Mayo though, down here in Cork sand is shite without paying 600 quid for a load, scudd is an absolute must down here, about 3:1.

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