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Posted: Thu Aug 27, 2009 11:49 pm
by Bob_A
I’ve got a question.
Rather than write loads and the bore the pants off you I’ll try to be brief, I've had it pointed that it’s a question that can only be accurately answered by a site visit so I’m only after best guesses and general advice.
My proposed patio will be (almost) square of 8mX8m, I’ll be using Indian Sandstone.
I want the area to have a endfall of 1:60 (manufacturers recommendations) but I also want it to have a crossfall.
My question is how much crossfall can I introduce before the patio gets too uncomfortable to use, items sliding on tables etc.
How about endfall=1:60 and crossfall=1:90 as a starting point, would that be ok?
Why do I want to introduce a crossfall? There’s a few reasons which I can go into if needed but I’m trying to keep this post brief.
Thanks for reading
Bob
Posted: Fri Aug 28, 2009 12:02 pm
by Tony McC
Keep the crossfall to a minimum. You have ample endfall, so introducing a crossfall will effectively increase that and you reach a point (somewhere around 1:50) when the TOTAL fall become uncomfortable for patio usage.
With an endfall of 1:60 plus a crossfall of 1:90, you would have a total fall of around 1:51
...so I wouldn't push it much more than that.
Posted: Fri Aug 28, 2009 1:43 pm
by Bob_A
Tony McC wrote:...so I wouldn't push it much more than that.
Will be taking your advice and definitely won't be pushing it any further. I might reduce the endfall a little.
Thanks for that Tony much appreciated 
Posted: Thu Sep 10, 2009 4:15 pm
by Bob_A
Just to recap I'm having an Indian Sandstone patio.
I will need to drain it.
I'm considering linear drainage running into perforated pipes or this idea
http://www.pavingexpert.com/drain14.htm#system
I'm sure both will work so it may come down to looks and ease of construction. The infiltration system with the pebble dressing on top will certainly be easier to construct and it may look more natural against the sandstone rather than linear drainage with it's more modern modular looks.
Down to me I suppose but if I go for the infiltration system could I add something between the pebbles and grass to make it easier to use a lawn mower. It doesn't have to be particularly wide just enough for the lawn mower wheels to ride on.
Cheers
Posted: Fri Sep 11, 2009 10:13 am
by Tony McC
You could use a mowing strip - in fact, it would be a really good idea as not only would it make mowing easier, it would reduce the risk of organic detritus from the garden getting into the filter drain.
I've updated the cross-section drawing to shown this change
Posted: Fri Sep 11, 2009 1:21 pm
by Bob_A
I'll order some extra flags or something similar for the mowing strip then.
Cheers
Posted: Fri Sep 11, 2009 3:23 pm
by irishpaving
Have you sorted that nerve yet Bob.
Posted: Fri Sep 11, 2009 4:29 pm
by Bob_A
Yes mate thanks for asking.
I was off work for a month and took Tramadoll for 3 weeks, 3 weeks of sedation really as I slept most of the time.
Took it easy for a few more weeks after that but have been recently preparing the sub grade and hope to be ordering the sub base soon.
So progress is being made albeit dead slow as that's my work rate even when I am fit LOL
What's this all about :laugh:
I know I've spelt Tramadoll wrong but if you spell it correctly the forum changes it to peardrops.
What's the story behing that?
Try it yourself :p
Posted: Fri Sep 11, 2009 5:23 pm
by dig dug dan
this is because certain individuals register and advertise certain drugs on here. The "spamtwats" as tony has christened them, also post other drug info and these certain keywords get cleverly changed by a special programme the gaffer has inserted.
Sometimes you can get "custard" to come up , but i can't remember which words trigger it!
Edited By dig dug dan on 1252686359
Posted: Sun Oct 04, 2009 10:15 pm
by Bob_A
My garden is on a hill so my patio needs levelling out a little. To contain the sub base I've built a 4" retaining wall made of standard bricks.
It's not a very high wall, 3 courses above ground level at one end down to zero bricks at the other end.
My question is once I've put the sub base in is there a possibility that I could damage the wall with my Wacker.
I don't mean by careless use of the wacker physically hitting the wall but the sub base material pushing into the wall as it's being compacted.
The mortar is only a day or two old and I'm worried I might break the bond it has with the bricks.
Can this happen if so what's the best way to avoid it?
Thanks
Posted: Wed Oct 07, 2009 6:57 pm
by Bob_A
Bob_A wrote:Can this happen if so what's the best way to avoid it?
Well I'm pleased to say it didn't happen.
Would've been right fecked off if it had though.
Posted: Thu Oct 22, 2009 10:46 pm
by Bob_A
I've taken delivery of my flags/slabs.
They are Stoneflair Purestone in 4 sizes 900x600,600x600,600x290,290x290.
They are calibrated to a 22mm thickness to make them easier to lay but the downside is that at 22mm you have to be careful when handling the 900x600's.
I've got my sub base down and was thinking of using a 40mm thick semi dry/moist mix bedding layer. As the flags/slabs are relatively thin I'd appreciate any guidance of what sharp sand/ cement ratio to use and whether I should add any plasticiser or other additives.
Thanks
Posted: Fri Oct 23, 2009 1:56 am
by lutonlagerlout
If you are using a belle 150 type mixer we normally use 14 shovels of sand to a half bag of cement with a good dollop of PVA/SBR in the mix (i have always used PVA with good results) personally i like it wet enough so that the agitators cut through the mix rather than turn it, you just need to be careful not to splash it
all the best
LLL
Posted: Mon Nov 02, 2009 11:32 pm
by Bob_A
lutonlagerlout wrote:............with a good dollop of PVA/SBR in the mix (i have always used PVA with good results)..........................
I'm still experimenting but I'm working on that I need about 5 litres of water to every cement mixer load (75Kg (3 bags)of sharp sand + 12.5Kg (0.5 bags) of cement)
So what do you chaps consider to be is a good dollop?
I'm talking very roughly here, is it a couple of tablespoons, a small tea cup, a mug or a pint?
I don't need an exact answer just need a starting point, don't wanna putting in far too much or far too little
Thanks!
Posted: Tue Nov 03, 2009 10:34 am
by Tony McC
The dosage rate for PVA or SBR is normally given with the product or the data sheet that is supposed to accompany it. Because the different suppliers provide differing dilutions, it's always a good idea to see what they say in the bumf. From memory, it's summat like 100ml per 25kg cement, but, as I say, check the product to be sure.