Crash course in rendering a retaining wall.....

[machtucker]

Good evening everyone,

 

My next job in the landscaping project is to render the retaining wall (see photo). Is there some info online that provides any info? I've watched a few YouTube videos etc but wondered if anyone has any nugget tips?

 

I will need to get some beads for the corners and some stop beads for the back of the wall as the render wont go all the way down there as I have damp proof membrane and soil against the bottom portion. Any recommendations on what beads to get? My block work is probably not complete plumb or level so there may need to be some adjustment of the beads to get them level, how would you recommend attaching them?

 

I know I will need to do a scratch coat and then let that dry then apply a final coat. Any recommendations on render mixes? Should I use sand and cement buy a special render mix?

 

Many thanks in advance.

 

Ed

[Redbeard]

I think I would be tempted to buy some base-coat EWI-type render. If you have never done any before I would suggest use a 10mm toothed trowel, then let that coat stiffen up a little before doing a second coat with an ordinary trowel. The 1st coat will act as a guide for the 2nd. You may not need mesh but I think I would use it. Lightly 'float' the glass-fibre mesh over the 'peaks' of the toothed coat , the=n trowel on render till the mesh is no longer 'ghosting through', or as close as you can get. You may need to do a final base coat to lose all the 'ghosting'. Final final coat (after 4 days, IIRC) is self-coloured top-coat 'gritty' render.

 

Lots of people sell this stuff - sometimes local merchants, but I have used EWIStore a lot.

[nod]

Pay someone for a days work 

Your going to be looking at messy render for a long time 

[machtucker]

5 hours ago, Redbeard said:

I think I would be tempted to buy some base-coat EWI-type render. If you have never done any before I would suggest use a 10mm toothed trowel, then let that coat stiffen up a little before doing a second coat with an ordinary trowel. The 1st coat will act as a guide for the 2nd. You may not need mesh but I think I would use it. Lightly 'float' the glass-fibre mesh over the 'peaks' of the toothed coat , the=n trowel on render till the mesh is no longer 'ghosting through', or as close as you can get. You may need to do a final base coat to lose all the 'ghosting'. Final final coat (after 4 days, IIRC) is self-coloured top-coat 'gritty' render.

 

Lots of people sell this stuff - sometimes local merchants, but I have used EWIStore a lot.

Wow, that sounds pretty complicated. Why is rendering so complicated! I was expecting to whack some beads up, put a scratch coat on then a final coat but this is what I feared. Maybe I’ll look into getting someone to do it for me. Would be a shame as I’ve done everything from scratch myself up until now. YouTube has been my friend. 

[machtucker]

4 hours ago, nod said:

Pay someone for a days work 

Your going to be looking at messy render for a long time 

Yes, I will get some quotes. How much would I be looking at to get someone in for this?

[nod]

6 hours ago, machtucker said:

Yes, I will get some quotes. How much would I be looking at to get someone in for this?

Nice easy day for someone £200-300

 

[joe90]

Funnily enough I can plaster ok but crap at rendering, no idea why. (Get someone in)

[saveasteading]

10 hours ago, machtucker said:

sounds pretty complicated

Not complicated, just surprisingly difficult.

I can't make it smooth so have settled for the Mediterranean rustic  look of deliberate trowel swoops.

If you want flat, then for  a pro it's quick and easy. They do that and only that every day, and get good at it.

[machtucker]

For £2-300. That sounds like a much better idea. I don't mind it being perfect but it sounds like a bit of a pain. 

[Redbeard]

@nod is right, but if you are really wanting to do it yourself the 'toothed trowel-depth-guide' method works. I think perhaps my description is more complicated than the doing. Just a bit of practice so as not to try to 'go over' when the coat below is too wet.

Edited April 28 by Redbeard

[saveasteading]

1 hour ago, Redbeard said:

toothed trowel-depth-guide' method

I didn't know this. Can you explain why the toothing helps get it flat?

 

As a poor plasterer, I like the products with a high latex content. It is stickier to the wall, less effort  to float and takes a while to go off (for second chances)

[nod]

1 hour ago, saveasteading said:

I didn't know this. Can you explain why the toothing helps get it flat?

 

As a poor plasterer, I like the products with a high latex content. It is stickier to the wall, less effort  to float and takes a while to go off (for second chances)

It doesn’t 

base coat needs to be flat and lightly scratched 

Think he’s getting mixed up with top coat A toothed feather edge is used to get the air out Then flattened back down 

[saveasteading]

15 minutes ago, nod said:

base coat needs to be flat

That's my problem. One of my problems.

[nod]

4 minutes ago, saveasteading said:

That's my problem. One of my problems.

You don’t need to put a base coat on 

It can be pressed into the first layer of render Then coated over with 15 mil of render after an hour 

[ToughButterCup]

1 hour ago, nod said:

....Then coated over with 15 mil of render after an hour 

 

Then, a long hot bath and or a trip to your physiotherapist: in my case a sado-masochistic-pain-inflictor- who-makes-me-feel-better-because-she-stops. 

But fancy this: she's a German refugee living and working and paying tax in the UK. 

Come here since Brexit ! WhassaMatterWithHer?

 

[SteamyTea]

1 hour ago, ToughButterCup said:

in my case a sado-masochistic-pain-inflictor- who-makes-me-feel-better-because-she-stops

Kinky (expletive deleted)er.

 

Did you ever see Private Schulz, Salon Kitty was the parlour name.

[Redbeard]

 

  4 hours ago, saveasteading said:

I didn't know this. Can you explain why the toothing helps get it flat?

 

As a poor plasterer, I like the products with a high latex content. It is stickier to the wall, less effort  to float and takes a while to go off (for second chances)

Nod said: It doesn’t 

base coat needs to be flat and lightly scratched 

Think he’s getting mixed up with top coat A toothed feather edge is used to get the air out Then flattened back down 

 

Sorry, I was not assuming much 'out-ness' on the substrate. The toothed trowel approach (which I always used for plastering and rendering on wood-fibre) does not get it flat - simply helps you keep even as each subsequent coat goes on, so yes, you do need to get the first coat fairly right. 

 

Bear in mind I am talking about renders and plasters designed for thin-coat application, not at more 'traditional' thicknesses. 

[machtucker]

I've got someone to come and quote tomorrow to do the rendering but there's something in me that's telling me to have a go myself. 🤦‍♂️

 

If I did go down that route I'm guessing I will put beads around all the edges. Should I put a stop bead at the base of the wall? If that's the case then ruling off will be easy as I can just get a straight edge a run it over both beads which (should) make it perfectly flat, right?

 

I am planning on installing so low voltage lights by Techmar on the wall too. They require a 10mm hole for the cable, should I drill that before doing the rendering or after?

 

Many thanks,

 

Ed

 

[Iceverge]

Go for it!

 

It's only a wall and you can have the satisfaction of learning. What's the worst that can happen. 

 

I would mix 3:1 sand cement for a scud coat. Throw that on. 

 

4:1 for a scratch coat.

 

5:1 for a finish coat. 

 

Sponge finish. 

 

You can put battens into the wall to get it level. And remove them once you're close enough and fill in the gaps they left. 

 

https://youtube.com/@macplastering?si=nnB3dXmray0UDeOa

 

This lad is easy enough to understand. 

[machtucker]

Thanks very much, that wall is very similar to the one I have. I had a chap come around yesterday so I'm interested to see how much the quote is.

[machtucker]

Should I drill the holes through the blocks for the lighting cables before the render is applied or after?

 

Many thanks,

 

Ed

[Mr Punter]

1 hour ago, machtucker said:

Should I drill the holes through the blocks for the lighting cables before the render is applied or after?

 

Do it after.  They will get in the way and make the renderer even more angry.

[machtucker]

Can anyone recommend the best place to get 10mm plastic render beads from?

[Redbeard]

Depends where you are. My local builders' merchant (in Yorkshire) sells them. Screwfix do them - 5 x 2.5m for £33. https://ewistore.co.uk/shop/external-wall-insulation/white-corner-bead-no-mesh/ do them for £3.59 each but no doubt carriage will up it a bit.

[machtucker]

14 minutes ago, Redbeard said:

Depends where you are. My local builders' merchant (in Yorkshire) sells them. Screwfix do them - 5 x 2.5m for £33. https://ewistore.co.uk/shop/external-wall-insulation/white-corner-bead-no-mesh/ do them for £3.59 each but no doubt carriage will up it a bit.

Yeah I saw the screwfix deal. Looks like it'' be fairly pricey just for the beads. I've worked out I need about 42m of 10mm corner beads and 19m of stop beads.