How to screed.

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currymunster

currymunster

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Do the odd screed job here and there and usually get away with but after watching one of the pros on you tube I'd like to learn some of that finer detail - If you can help??

At the mo doing a 4 to 1 sharp sand mix - in mixer till wet enough to ball in hand.
Go round edge doing box screed and then central ones and fill in.
When filling in I'd like to be able to get a nice finish. At mo i poly float and steel off after.
when screeding it rips and leaves gaps no matter what I do.
Would and aluminium straight edge solve that as opposed to the standard 1800mm level I'm using.
Also is it the mix - maybe a secret ingredient??
Oh and yes I am a plasterer - just don't do a lot of screeding.
Thanks Guys
James
 
johniosaif said:
You need to pack down your ruling screeds firmer.
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Thanks - When you say ruling screeds firmer do you mean the box screed as I know it.
It's the screeding bit between the box creeds I have trouble with.

I watched this guy and when he rules of it's more or less perfect.
Mine has loads of bits missing and takes ages to fill in with poly float.
His mix looks really sandy and easy to smooth over where as mine is like a dry render with sharp sand!!

How to lay floor screed, call 01204 656649, installing floor screed, underfloor heating screeding - YouTube
 
there are several different methods to screed. the screed [ the whole floor is called screed] should be compacted, you need a metal screeding rule, try not to use a float as this will push the screed out of shape. rule and trowel.
a screed put through a cement mixer should be 3 to 1. a ready mixed screed delivered through a screed pump on a lorry is better at 4 to 1.
flood the screed next day and cover with poly for 7 days , because screed is mixed semi dry the cement will not reach full strength if it is not flooded. a high class screed will be flooded and covered each day for 10 days.
 
currymunster said:
Thanks - When you say ruling screeds firmer do you mean the box screed as I know it.
It's the screeding bit between the box creeds I have trouble with.

I watched this guy and when he rules of it's more or less perfect.
Mine has loads of bits missing and takes ages to fill in with poly float.
His mix looks really sandy and easy to smooth over where as mine is like a dry render with sharp sand!!

How to lay floor screed, call 01204 656649, installing floor screed, underfloor heating screeding - YouTube
Click to expand...

Curry his mix isn't sandy just semi-dry as it should be. A 4:1 mix is fine.
Don't worry about thumping it down like some do to compact it. When doing your box screeds put the gear down about 15mm thicker than the finished screed depth and then using either an ali or wooden edge rule to level. When infilling between then screeds just repeat the method used for the screeds except rather than using a level rule down to the box screeds.
Oh and don't use a small mixer they're worse than useless, I use a Winget 150Ft. This gives loads of room for a one bag mix to move about without it balling.
 
screed does need to be compacted if it is to receive the slide hammer test to find out if the class of screed laid meets the quality of screed that has been paid for
 
malc said:
screed does need to be compacted if it is to receive the slide hammer test to find out if the class of screed laid meets the quality of screed that has been paid for
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If you've laid the gear out at 80mmish and then rule it down to 65mm it has been compacted, just like that guy did in that clip Curry put up.
 
Right I can't quote everyone.
Thanks for your help guys.
I'm using a level to rule off as it's a straight edge with two convenient handles in. I am ruling off to the box screed already done rather than watching the bubble while ruling off.
From the sound off the guys poly float the mix sound very dry yet when I do it that dry its like chasing powder around yet he does it with a great finish with ease!!!!
So - I'm assuming the a aluminium box edge from refina will help but me thinks the mix might wrong?
I'm adding a cementone waterproofer and retarder which says on the tin for screeds as well as rendering.
Maybe 3 in 1 would not be so sandy. How do I tell the dryness when mixing?
Oh and balling in the mixer - I know that well but this is for a builder and I have a lad supplied to mix.
Mind you the mix is never the same stiff mortar to sand thats dryer than when it came out of the bag!!!!
Hopefully last day tomorrow!!!
 
Id say if you have bits missing its like Andy says, your not having your bays full enough when you rule off,if your mix is right,and the strength wont mater to much its more the dryness/wetness its should look almost finnished in a few back and forth rules, poly rub up then trowel finnish.Also i normally through a coat over the floor and this compacts as you walk back and forth laying your screed.
 
kebab king said:
Id say if you have bits missing its like Andy says, your not having your bays full enough when you rule off,if your mix is right,and the strength wont mater to much its more the dryness/wetness its should look almost finnished in a few back and forth rules, poly rub up then trowel finnish.Also i normally through a coat over the floor and this compacts as you walk back and forth laying your screed.
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what kind of coat?............duffel, parker, trench















:RpS_blushing:



Soz JJ
 
kebab king said:
Id say if you have bits missing its like Andy says, your not having your bays full enough when you rule off,if your mix is right,and the strength wont mater to much its more the dryness/wetness its should look almost finnished in a few back and forth rules, poly rub up then trowel finnish.Also i normally through a coat over the floor and this compacts as you walk back and forth laying your screed.
Click to expand...

Definatly have the bays full enough with the amount I drag off. Like you say it's probably more to do with the mix.
Tried it really dry today and got better results but as said earlier I don't think it was wet enough to cure properly and on a lot of my small jobs I can't price in to go back next day to soak it?? I think an ally rule will help as well. It's got to the stage that I hate doing screed jobs because I can't get it how I would like it - Dissheartening!!
 
currymunster said:
Definatly have the bays full enough with the amount I drag off. Like you say it's probably more to do with the mix.
Tried it really dry today and got better results but as said earlier I don't think it was wet enough to cure properly and on a lot of my small jobs I can't price in to go back next day to soak it?? I think an ally rule will help as well. It's got to the stage that I hate doing screed jobs because I can't get it how I would like it - Dissheartening!!
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its the same as owt else , practice..............you'll get there marra.....................:RpS_thumbup:
 
Curry don't make it 3:1 stick with 4:1 but get it mixed right.
Take a handful of mix and grip it tightly, if it remains as a ball when you open your hand then it's probably good to go. When you start to tip the into the barrow rub the back of the shovel back and forth a couple of times. If you get a really cementous surface then it's to wet, if you get a rubbed up effect with just a small amount of cement coming to the surface you'll know it's right. Different sands will need to be mixed differently to each other.
When it comes to rules you don't have to have aluminium ones, some nice straight 3x2 makes great rules.
Also don't worry about going back to flood the screed. I always tell the builders/clients to do so and they never ever do yet I've never had a problem with one of the many hundreds of screeds I've done.
 
Don't do it anymore, but always remember asking the labourer how many wheel barrows were left and he replied," this is the only one I have seen"
 
James,

We have a 180 m2 bungalow to do in Sittingbourne in about 3 weeks. Pop your head, run the barrow for a while, and Ill give you a few pointers.
 
I would snap his hand off if I were you James, a day with an experienced (I'm not implying your not) tradesman is worth its weight in gold. That's the beauty of our game, we can always learn and improve
 
mark ross said:
James,

We have a 180 m2 bungalow to do in Sittingbourne in about 3 weeks. Pop your head, run the barrow for a while, and Ill give you a few pointers.
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About three weeks to do just 180m2 Mark, I think you'll be getting pointers off James:RpS_wink:
 
dont forget the guy you watch on youtube probably screeds every day, i would use 3-1 screed and an aluminium box straight edge would definitely make it easier
 
mark ross said:
James,

We have a 180 m2 bungalow to do in Sittingbourne in about 3 weeks. Pop your head, run the barrow for a while, and Ill give you a few pointers.
Click to expand...

Hi Mark,
How are you keeping?
I might just take you up on that offer Mark.
PM the date and details and I'll try and book my diary.
Very kind of you my friend - be nice to see you again.

James
 
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