How would you point this?

Patio flagstones (slabs), concrete flags, stone flags including yorkstone and imported flagstones.
EViS
Posts: 19
Joined: Tue May 15, 2012 11:12 am
Location: UK

Post: # 78119Post EViS

haggistini wrote:805 that's the shit!
Or you can bush in semi dry and soak the lot... and when the weeds, ants and moss kick in you'll get that true rustic / drift wood effect you may be after? but this will fail in no time!
:)

Now that you have seen the joints in the above pictures, is your view that 805 will work and remain in place?

TBF, having ants mine out a dry mix isn't what I'm after :;):. But neither am I willing to lift the whole thing up as only a small % of joints are as small as 2mm. The problem (as you can gather) is how to get a sand of sort into the joints without making a mess.

EViS
Posts: 19
Joined: Tue May 15, 2012 11:12 am
Location: UK

Post: # 78121Post EViS

DNgroundworks wrote:No you pre-wet the whole area first, then pour the slurry on after mixing with a paddle mixer in the bucket it comes in, then squeejy/brush it around wait for it to dry a bit then bursh any excess off, its really easy
As LLL said, pouring a slurry across the entire area is a big no-no for this particular paving.

EViS
Posts: 19
Joined: Tue May 15, 2012 11:12 am
Location: UK

Post: # 78122Post EViS

lutonlagerlout wrote:A slurry will mess that up big time
what you have done wrong elvis is that you have more or less butt jointed them
i take it there is an unrestrained edge to all this?
mix sbr and cement till you get a wall paper paste consistency then carefully paint it over the exposed joints at the edge of this area
the joints are the ones on the vertical faces ,do not put it anywhere near the top

the following day when this has gone off ,fill with kds and leave ,top up as required
the bottom line is that you have laid it wrong and this is a diddle and fake it solution
all the best
LLL :)

All sides are either butted up to concrete gravel boards, or have been haunched with the same mortar mix as used for the bedding. Only one part (not the full width of the patio) is unrestrained as there is a channel.

I take it the idea of using SBR is for the KDS to bond somewhat to the paving? I can see what you mean by this being a bit of a 'bodge', but I understand your solution nonetheless.

However (yes, sorry!), do you truly believe that based upon the photos of the actual paving joints, that any form of sand/cement or resin will begin to flake out after a while? Even the resins which state that they are made for paving joints from 3mm (I appreciate that a small % of my joints are less than this)?

ps. I'm not trying to argue here or waiting for you to say something that I want to hear. I'm simply not convinced that you can see that only a small % of joints are truly butted or at 2mm.

Pablo
Posts: 1990
Joined: Sun Mar 25, 2007 10:49 pm
Location: N/Ireland

Post: # 78123Post Pablo

I've laid these a few times and they can't be resin slurry jointed because the surfaces are like sand blasted oak and are to rough to brush anything off without leaving a sh#tload of it still stuck in the rough bits. Normal slurry pointing is marginally easier but you have to be careful to hose all the cement out of the rough bits and it's beyond a diyer's remit so you're going to have to grind the joints with a mortar rake and gun and strike the mortar into place. Once it's pointed you don't see the cuts and they weather fairly quickly so it'll all tone down soon enough.
Can't see it from my house

EViS
Posts: 19
Joined: Tue May 15, 2012 11:12 am
Location: UK

Post: # 78125Post EViS

Pablo wrote:I've laid these a few times and they can't be resin slurry jointed because the surfaces are like sand blasted oak and are to rough to brush anything off without leaving a sh#tload of it still stuck in the rough bits. Normal slurry pointing is marginally easier but you have to be careful to hose all the cement out of the rough bits and it's beyond a diyer's remit so you're going to have to grind the joints with a mortar rake and gun and strike the mortar into place. Once it's pointed you don't see the cuts and they weather fairly quickly so it'll all tone down soon enough.
By "normal slurry pointing" are you referring to a traditional mortar mix of sand/cement?

When you have laid these in the past, what sort of joints widths did you end up with and what mortar mix did you use?

Pablo
Posts: 1990
Joined: Sun Mar 25, 2007 10:49 pm
Location: N/Ireland

Post: # 78127Post Pablo

Disregard anything to do with slurry type pointing it's not going to work and you'll ruin your paving. I've laid them in several displays for Marshalls over here and in a few patios etc subsequently after clients saw my advertising. I don't recall having any dramas with the joints (10mm) just keeping the mortar out of the roughness. I slurried a couple of them but it's not something you're going to have the skill for and gunned the rest of them which looked better and is within your limits.
Can't see it from my house

EViS
Posts: 19
Joined: Tue May 15, 2012 11:12 am
Location: UK

Post: # 78128Post EViS

Right, I guess that opening up the joints is the only way forward as a few of you have already suggested.

What would you say is the minimum width the joints can be to then fill with mortar and create a durable joint? Most mortar rakes (which look like drill bit attachments for grinders) are around 8mm aren't they? Will these not wear out quickly trying to cut through concrete slabs?

lutonlagerlout
Site Admin
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Location: bedfordshire

Post: # 78133Post lutonlagerlout

elvis you are a pessimist fella
solution 1
pour KDS in the joints and see what happens
(i have a client i did a patio for 15 years ago at the time him and his wife couldnt decide on pointing so we filled the joints with kds and they both liked it,every spring they jetwash the patio and fill it with new kds
costs about 20 quid a time)
diy -
solution 2
grind out and use gunpoint
fairly expensive and labour intensive
diy++
solution 3
lift and relay
$$$
so there ya go
LLL
"what,you want paying today??"

YOUR TEXT GOES HERE

EViS
Posts: 19
Joined: Tue May 15, 2012 11:12 am
Location: UK

Post: # 78135Post EViS

lutonlagerlout wrote:elvis you are a pessimist fella
solution 1
pour KDS in the joints and see what happens
(i have a client i did a patio for 15 years ago at the time him and his wife couldnt decide on pointing so we filled the joints with kds and they both liked it,every spring they jetwash the patio and fill it with new kds
costs about 20 quid a time)
diy -
solution 2
grind out and use gunpoint
fairly expensive and labour intensive
diy++
solution 3
lift and relay
$$$
so there ya go
LLL

Pessimist or just wants to do the job properly (despite cocking up on one part due to thinking it will look better aesthetically and not thinking about the practicality of pointing) :).

Any advice on how much to grind out and whether to use a diamond disc or a mortar rake as suggested by Pablo?

Pablo
Posts: 1990
Joined: Sun Mar 25, 2007 10:49 pm
Location: N/Ireland

Post: # 78139Post Pablo

A mortar rake is a diamond disc just a very thick one either way you're best to try for at least 5mm but preferably 8mm or more. Once you've ground it pressure wash it all off and get pointing.
Can't see it from my house

lutonlagerlout
Site Admin
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Location: bedfordshire

Post: # 78144Post lutonlagerlout

Pablo wrote:A mortar rake is a diamond disc just a very thick one either way you're best to try for at least 5mm but preferably 8mm or more. Once you've ground it pressure wash it all off and get pointing.
if elvis couldnt lay the slabs correct i feel that raking and repointing would be a bridge to far
those wet cast wood slabs would be a bugger for a pro to grind out well
IMHO try KDS and give it a month or two
suck it and see as they say
on here we all like to do jobs properly but you elvis are between a rock and a hard place and you could end up ruining the lot if you noise it up with a grinder
LLL
"what,you want paying today??"

YOUR TEXT GOES HERE

local patios and driveway
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Post: # 78145Post local patios and driveway

Gripfill?

Thats a forum joke dont take that advice

EViS
Posts: 19
Joined: Tue May 15, 2012 11:12 am
Location: UK

Post: # 78150Post EViS

Alright, thanks for all of the advice fellas. Best to use the solvent-free (yellow) gripfill so not to contaminate the slabs, yeah :D? (also a joke btw)

Three final questions in regards to mortar pointing:

1. What's the best mortar mix to use for pointing? I see some people mentioning plastering sand whilst others mention sharp sand or building sand.
2. Which 'mortar' gun do you lot most recommend? (I can see these being bloody expensive though)
3. If I end up not grinding out the narrower joints (due to risk of damaging the slabs) and still point with mortar, is the problem that the mortar will eventually 'flake' out (for want of a better term?)? Or is the problem only that it will be difficult to get the mortar into the small gaps in the first place?

Carberry
Posts: 1366
Joined: Fri Apr 15, 2011 9:05 pm
Location: Edinburgh

Post: # 78155Post Carberry

EViS wrote:Alright, thanks for all of the advice fellas. Best to use the solvent-free (yellow) gripfill so not to contaminate the slabs, yeah :D? (also a joke btw)

Three final questions in regards to mortar pointing:

1. What's the best mortar mix to use for pointing? I see some people mentioning plastering sand whilst others mention sharp sand or building sand.
2. Which 'mortar' gun do you lot most recommend? (I can see these being bloody expensive though)
3. If I end up not grinding out the narrower joints (due to risk of damaging the slabs) and still point with mortar, is the problem that the mortar will eventually 'flake' out (for want of a better term?)? Or is the problem only that it will be difficult to get the mortar into the small gaps in the first place?

1. Depends on the quality of sand you get from your local builders merchants / quarry. Building sand does me fine. Recent thread here discussing it

2. Durgon pointing gun from Londonstone

3. 2mm joint is too thin for any mortar we can mix ourselves. It will end up being too weak and will break / crumble / flake. More of a pain in the ass to get the mortar in the joint too, but the main issue is the strength.

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