Rendering walls

[trevortine]

Hey guys, looking for a bit of advice on external rendering of walls that i have built in garden, never done it before but being ok at the plastering and knowing how to use a trowel its just mixes and sand types im wondering about. After reading up im gettin the idea of a 3:1 mix and the sand being 50:50 soft and building, im thinkin sbr would be essential here for good bond, I know its a bit off topic but advice on here beats the old diy sites, any advice appreciated!

[mikethetile]

sounds good to me

[Rad2474]

Why not try looking on here Plastering Forum | Plastering Advice | A Forum for Professional and DIY Plasterers in the UK

[garythetiler]

aston, whitebeam and doug boardley will be able to tell you, give them a pm and you will get expert advice

[Scott]

Post it on here cos i wanna read it too

[TF Ed]

hi trev

dont use building sand/ red sand for rendering mate..it shrinks and cracks, use washed sand...
1.sbr the wall as you mentioned to begin
2. 3 and 1 for your scratch coat with some water proofer in the mix..apply as if you skimming..if your right handed, start from the right going to the left...once you have done a reasonably sized section, key the scratch coat with horizontal waves..i usually flatten my scratch coat with a darby because it makes your render coat easier some people dont tho, they apply really flat with a trowel if the walls are good enough..
3. leave it a couple of days and then apply your rendering coat..this should be weaker than the scratch coat at around 4 and 1..no waterproofer required and no need to sbr before you lay this coat
4. tips on applying....do a section of wall you are comfortable with, then rule off vertically and then upwards. fill in any voids and rule off again.
5. finally , use your devil float to rub up and finish...some people use a sponge at the end but i dont and i dont think its necessary either but thats just my opinion.

different plasterers/renders have different mix ratio's depending on different scenarios...3 and 1 scratch coat and 4 and 1 render will be the most commonly used but people use 4 sand, 1 lime , 1 cement etc too so there are variables...


you can buy stainless steel/plastic angle beads and bell cast or you can use battens to finish at the edges and bottom of the wall ...

gooner and whitebeam will add there tips and recommendations too

hope this help
ed

ps , sand and cement work is harder than skimming and backing plasters so take dont play around with it too much, it isnt as forgiving and it can start to fall off..

[Scott]

Ed What do you mean by 'rule off'? Is that just going over with a straight edge?

[TF Ed]

Ed What do you mean by 'rule off'? Is that just going over with a straight edge?

thats it mate

[Phil Hobson]

Nice one Ed, that is spot on ,takes me back to the old days. Darby, blast from the past. Your dad should be proud of you

[trevortine]

Thanks very much aston, brilliant advice there, still got the walls to finish but they are as level and straight as if I was tiling!! When you say washed sand is this readily available?

[TF Ed]

yes mate, most/every builders merchants stock it....it contains more sand particles than building sand and less clay, so it compacts better....

[Dave]

Another Top advice post from a Tilers forums Trusted advisor..Good advice Ed..

[Diamond Pool Finishers]

[ame=http://www.youtube.com/watch?v=nEl9hTS1Nzo]YouTube - Absolutely Plastered - Rendering Demonstration of ruling off panel[/ame] if you go to you-tube there are tutorials to mate great advice from ED

[whitebeam]

Larger B&Q stores do a rendering sand which is well graded, on the final coat don't try to rubb/float finish it up to early otherwise the moisture will pull to the surface and the render will roll off

[david campbell]

yes mate, most/every builders merchants stock it....it contains more sand particles than building sand and less clay, so it compacts better....

is this the same as silver sand(maybe the local term for it up here)
i'm sure i've heard roughcasters using that name

[mikethetile]

ask for leighton buzzard washed sand

[diamondtiling]

ask for leighton buzzard washed sand

Is that off the beach Mike............??

[mikethetile]

yes Dom

leightons famous for its beaches

[TF Ed]

is this the same as silver sand(maybe the local term for it up here)
i'm sure i've heard roughcasters using that name

hi dave

as mike tile says, washed sand can have different names depending on the area its sourced from but if you ask for washed sand, any reputable builders merchants will know what you want and give you the right sand.

silver sand is even finer again...silver sand is used on block paving to fill in the joints.

ed

[Diamond Pool Finishers]

sand can be the bain of my life,it is deffrent where ever you go in the country!!!also ask for rendering quality on the end of sharp/washed

[Phil Hobson]

Ed might remember Mersey grit, the best screeding sand ever. We had a task in Texas finding a good grit sand, but found some top stuff in the end

[Diamond Pool Finishers]

i use leighton Buzzard whenever i can get it, around the home county's is easy, its harder!! to get anywhere els!

[doug boardley]

I go AWOL for a couple of days and I miss a plastering question, good advice given though (although as Ed says, some plasterers ratio varies, I tend to use a 4:1 scratch coat and a 4.5:1 top coat)

[Diamond Pool Finishers]

in swimming pools the render mix is 3-1 sand/cement, and waterproofer walls/floor

[Scott]

Leighton is famous for its sand we even ship it to the arab states!

[TF Ed]

Ed might remember Mersey grit, the best screeding sand ever. We had a task in Texas finding a good grit sand, but found some top stuff in the end

yes i do remember mersey grit phil excellent sharp sand for screeding as you said mate,,,

[trevortine]

in swimming pools the render mix is 3-1 sand/cement, and waterproofer walls/floor

What waterproofer do you use gooner and in what ratio?

[trevortine]

I go AWOL for a couple of days and I miss a plastering question, good advice given though (although as Ed says, some plasterers ratio varies, I tend to use a 4:1 scratch coat and a 4.5:1 top coat)

Ha ha!!! Should have asked you on facebook doug, will know the next time! Progress been stopped by weather now anyway!

[david campbell]

doesn't look like you'll be picking it up again till wednesday doug,supposed to rain for the next 30 odd hours

[whitebeam]

I use L/Buzzard sand mixed 50-50 with soft and for dashing a shovel of lime thrown in for good measure