Edge course methods

[hibread]

G'day guys! Great site full of invaluable information I must say

I'm about to start my paving project and have a few questions regarding any 'preferred' methods for this job.

I have a rectangular area (minus an already built in BBQ wall island contained within). 3 of the edges of the rectangular area are retaining wall and the 4th being a concrete slab I plan to pave up to (being level with).

I figure there is no need for a concrete bedding edge course as all pavers will be locked in on all 4 sides. So I guess my question is what's a good method to lay the edge course (which will be a border) so I can use it as a screed guide. If of course that's even the way to go? Would one concrete these in anyway regardless, or methodically rubber mallet down each one into bedding sand?

Could screed rails be the method of choice for this entire job including the edge course?

- My pavers are 400 x 400 x 40mm wet cast
- The rectangular area being paved is roughly 8m x 9m (minus the island talked about earlier)
- Body pavers between border course will be stretcher bond pattern

Thanks for any input guys!

[lemoncurd1702]

Initially I would have said screed the whole area first until I saw the size of the paving slabs/flags.
These would be best laid on a sand cement mix. Install your edging course first and use these as a guide to level your slabs.
Should look bonza mate.

[hibread]

Thanks for the reply mate!

I planned to just use bedding sand (on top of the base course of course). What benefit would a sand/cement mix have? And i guess you mean as dry mix and let cure on its own accord?

When you say install the edging course, which method are we talking about? Laying into a screeded sand bed? Or some sort of individual lay into mortar/sand etc?

A question regarding the screeding of the majority of the paving sand. Would it be best to attempt to screed the entire area first, or do it in sections, laying as I go?

I must say the exact procedure for this job is a little unclear to me. If I were to use screeding rails (I've got a couple lengths of 25mm steel rounds) for majority of the work (assuming edge course are installed at the same time as the body pavers), I'm thinking I'd spread the sand, partially compact, screed, then install up to near the 2nd screed rail. Leave that screed rail there, move the first one in a leapfrog system and repeat.

Sorry for so many questions. I'll have a trade in many things by the time I'm done with this back yard I tell ya!

Cheers guys!

*edit: just realized I should have posted this in the slabs and flags forum!

[mickg]

the benefit of adding cement to the sand is it becomes a bound layer making the patio rigid and less chance of any movement, rather than having a dry mix its best to mix the sand with cement in a mixer and add a little bit of water, we call it semi dry, if you get a handful and squeeze it into a ball in your hands it wont fall apart

if you do use a sand and cement screed make sure you wash your tools at the end of each day, nothing worse than using dirty tools full of sand and cement from previous days work :;):

we would lay the border first what is installed to your finished heights on all side, then you would use a tight string line from side to side on top of your border held in place with a weight, could be a couple of bricks or off cuts of flags etc to hold the line in position

this line is the finished height for you paving so you will screed the area off allowing the depth of the flag down from the top of the line less approx 2mm - 3mm so you can lightly tap the flag into the laying course . . . its that simple

post some photos when its finished

[hibread]

Thanks mick!

Edit: sorry wrote this long winded reply, but it seems I totally miss read your msg regarding the body pavers. I'll have a good think about it and get back to you. Thanks mate!

[mickg]

most home owners don't lay paving to the same specification that we do so laying on a sand bed is fine, just don't expect the paving to still be perfectly flat in a few years time

we construct all of our patios on a sand and cement screed but the big difference is a lot of the high end products we use are only 20mm thick so they do need to be stuck down to the laying course hence why we have to coat the rear side of the paving with a bond bridge - good job you don't live over here eh

EDIT... no problem I have left my reply in answer to your question

[hibread]

Thanks Mick. I'll start my work today on the edge course. Attempting the semi-dry approach. Cement and sand

So I guess the decision I need to make is how the body of the pavers are going to be done once the edge course is in. It appears as though the back of the pavers have been honed or profiled in some way, but still each paver isn't exactly the same as each other. 38mm seems to be common

If you were doing this job, every single paver would be individually laid into a semi-dry mix yeah?

Thanks again!

[mickg]

yeah if the depth is varying then the only way to get a professional finish at our standards would be to bed each individual flag into a semi dry mix, laid to a line so the edge is straight and each flag is tapped into position using a rubber mallet also to the line, if no rubber mallet then the timber shaft of a lump hammer will do the same job

[hibread]

Hey guys!

Thought I'd carry on the discussion here rather than start a new topic.

Progress has been slow but have most certainly made a start. Edge course is in and about a third of the body pavers. I decided to concrete bed the entire lot in with quite a dry 10:1 paving sand to cement mix. The mix still clumps, but looks sandy rather than slurry in the mixer.

My question or concern now is lots of the pavers rattle, when you walk over them. I've tried to be as critical as possible to check each paver that they don't rock after tapping them down (sometimes if you've had to tap too hard, they do get a bad rock which is obviously undesirable and I've reworked the obvious ones as I've gone along).

I gather there must be something I've done a little wrong with the bedding procedure (unless this is some how part and parcel?). I have cemented in other pavers before (of this same size) but used quite a wet slurry and never had this rattling or rocking problem.

Could I ask for any tips on avoiding this problem for the rest of my paving job, and any solutions to fix the current rattly ones? I've had dark day dreams about pouring in (through a funnel?) a very thin cement/water mix between the rattly pavers to see if the very shallow voids could be filled. Or even worse, pull up individual pavers and liquid nails them down...?

I haven't put any grouting in yet between the 3 mm paver gaps. And I haven't quite decided on the medium I'll use (sweeping sand, or actual tile grout for e.g.)

Cheers guys!

[lemoncurd1702]

Did you use a bond bridge as suggested by mick. If using a dry mix the slabs need some bonding agent brushed onto the bottom of the slab. Most use SBR or you could use pva but it sounds like you're past that point.

I think maybe lift the loose ones and stick down with your slurry mix of cement and water with sbr added and brushed on bottom of slab also.

Filling the joints with slurry won't do it.

[hibread]

Well don't I look silly. I read that part as lucky you don't live over here with 20mm flags so I disregarded that part. Certainly didn't parse that information oops!

I have got some ardex ultraprime. I'm finishing up for the day and laid a few priming the back of the paver with a slurry of the primer and cement. Also pulled up the first paver I laid (easy to get to) and did the same to both surfaces. See how that goes!

I'm also going to be using a wetter mix. Just as the mix starts going from sandy to a more homogeneous consistency

Thanks mate, can't believe the extra repair work I've given my self!

[r896neo]

I find a wetter mix easier to get a good full bed on, the mortar spreads better under your flag as you tap it down.

A semi dry mix is much tidier to work with but for the inexperienced i think it is harder to acheive a good solid bed with it.

If you still have rocking pavers something is not going right, try switching to a wet mix.

[mickg]

firstly makes sure you have washed the surface of the paving with clean water and a brush just in case any of the slurry has got on the face or edge of the paving, its easier now than in a few days time when its gone hard and it might not be able to be removed with ease

second, its a learning curve, we have been doing it for years so it comes second nature to us, don't beat yourself up over it, learn not to do it again and move forward

when you have tapped the flag into position to the line and done the final tap in the centre of the flag put your fingers on opposite corners of the flag and push down only lightly to see if there is any movement from corner to corner with the flag, then check the 2 opposite corners

did you see I typed "final tap in the centre of the flag", this helps not to have a rocker, if your final tap is to one corner then it can contribute to a rocking flag but this also depends if the bedding material was reasonably flat in the first place and the bed is of an even ish depth, as an example if the bedding was 25mm higher on one side than the other you would have to tap the flag off centre to get it down to the correct height if you understand what I am saying ?

post a photo of the stage your at and hopefully we can give you better advice, no one will belittle you as its a learning curve for everyone and long term other member will see this thread and may learn from it too

[hibread]

[IMG]http://i172.photobucket.com/albums....MG]

Let's hope that link works! Just to give an idea what I'm doing

The last few pavers I laid last night seem really good this morning. Not drummy at all. Sounds really solid. Just using a wetter mix and priming the surface of the paver.

The trouble is going to be fixing a whole heap of the rattly/drummy ones I've already done. Consensus on this being pure cement mixed with the a sbr? What sort of consistency?

Does sweeping sand help with reducing the feel under foot and any hollow sound to some degree?

Thanks guys!

[mickg]

from where I am sitting that looks absolutely fantastic mate, honest it does

our SBR is like milk, I'm not sure what your version will be like but you have to coat the back of the paving so it can't be too stiff, needs to be similar to wall paper paste so you can coat the rear of the paving with a nice thick coat and it not run all over the place