Planning patio levels

[toplondonchef]

Hi all..
Found this site a couple of weeks ago and must say it's absolutely brilliant - well done all

Helping a friend of mine to plan and then lay a patio at their house and have a couple of questions please;

Have dug down 160mm to allow for 75mm MOT 1 base,
50 mm damp mix sharp sand / cement, 35mm depth of slabs. Slabs are 450x450mm textured concrete (dont know technical name)
Area width is 7m x 2.3m depth and have allowed a fall away from house of 45mm

There is a concrete slab running along the house which will remain and this is where the patio slabs will start from, set at the same height

The patio will butt up to the remaining lawn but the lawn is really un-even across both planes, rising up steeply at the edges where raised flower beds have been grassed over years ago

As my starting level has to be the concrete slab, and incorporating a 45mm fall, the edge of the patio slabs will be 75mm below the edge of the lawn (at the highest point) This will look pretty ugly, result in a step and the lawn edge will collapse when walked on

Sorry for the long story but any ideas please.....
I'm well happy doing any kind of DIY task but this is my 1st time laying a patio so any advice will be greatfuly recieved and many thanks

[Carberry]

Edging along lawn would probably be your best bet. give us the name of the slab or a photo and a budget and we can recommend something.

Only other thing I would consider is levelling the lawn either by stripping it, levelling and relaying or throwing some top soil over low spots and seeding.

[toplondonchef]

Thanks very much Carberry for your quick response;

Can't remember name of slabs but will get tomorrow

Not much to take a photo of yet as just finished digging and setting string lines, tomorrow the MOT goes down but slabs wont be touched until Monday

I was thinking of either some log edging sunk in just below lawn surface or some treated timber battens

Did suggest levelling lawn by scalping but his missus is going bananas already about any mess created and is not keen on any further "butchering" of her beloved garden

Did say "you have to look through the mess to a perfect end result that you will be proud of" but just got an icy stare - Oh well it's my mate that has to live with her !!

1 other question if I may ....
The slabs being used seem quite dusty and pourus so do I wet the backs of them before laying on my damp mix, also seen PVA being mentioned to improve adhesion (obviousely waterproof version) but is this really needed
Thanks again Carberry

[Carberry]

I would lay them on 25-40mm bed rather than 50mm.
If you want to aid adhesion use SBR, 100ml per mix and you will have trouble lifting them.
No need to wash them, but it wouldn't harm them.

Tell him to distract his missus with a shiny new zirconia, tell her it's a diamond (she won't know the difference unless she is like my ex who got every bit of jewellery valued) then sort the lawn

[toplondonchef]

Hi Carberry and many thanks for your continued help;

The slabs are Bradstone textured grey 450 x 450
Have now decided on using log edging for the high areas of the lawn and the Mrs is reasonably happy !

As I've not layed a patio before (only a few slabs on a sand bed) I've been reading this site like crazy and making notes and for some reason had written down a 50mm mortar bed. You mention a 25-40mm bed but I've already compacted MOT and set levels and allowed for a 50mm bed - is this an issue ? Sure that I've read that a 25mm bed makes levelling harder as not much depth for adjustments and also you may get some large pieces of MOT slightly higher

Have got Febmix Plasticiser to use in the mortar and was going for a damp, 6 - 1 mix - is this ok

1 more question please :Do I need to put a thin layer of sharp sand over the compacted MOT (is this called blinding) ? and compact lightly or no need

Once again, many thanks for taking the time to read and post back, very helpfull

[lutonlagerlout]

you are on the right track TLC,better 50mm than 20mm bedding
you seem to have done the right thing and read the site first,just take your time and dont be scared to redo something if its wrong
we all make mistakes sooner or later
good luck
LLL

[Carberry]

Hi Carberry and many thanks for your continued help;

The slabs are Bradstone textured grey 450 x 450
Have now decided on using log edging for the high areas of the lawn and the Mrs is reasonably happy !

As I've not layed a patio before (only a few slabs on a sand bed) I've been reading this site like crazy and making notes and for some reason had written down a 50mm mortar bed. You mention a 25-40mm bed but I've already compacted MOT and set levels and allowed for a 50mm bed - is this an issue ? Sure that I've read that a 25mm bed makes levelling harder as not much depth for adjustments and also you may get some large pieces of MOT slightly higher

Have got Febmix Plasticiser to use in the mortar and was going for a damp, 6 - 1 mix - is this ok

1 more question please :Do I need to put a thin layer of sharp sand over the compacted MOT (is this called blinding) ? and compact lightly or no need

Once again, many thanks for taking the time to read and post back, very helpfull

As LLL said, 50mm is better than 20. It's not an issue if you have already set levels to that.

Depends on how well the type 1 is compacted. If you have some larger lumps near the top that aren't really bound then you can stick some sharp sand over it and compact it just to tighten everything up. Much more of an issue on a driveway or if you have a small bedding layer to work with.
Damp 6:1 is fine, no need for plasticiser

[toplondonchef]

Thanks as well Mr Lager Lout - must say I prefere bitter myself though (even though 1 swift cold lager on a hot day cant be beaten I will admit, but then followed by a barrel of bitter)

Anyway, back on topic.....

Whats your thoughts on a thin layer of sharp sand over the MOT ? Required or not ? and while you're online 1 more if a may !!

Best mix / method for mortar joints (I know that this will start a lively debate) !

Was planning on using the same as the bedding mix - 6 sharp sand / 1 cement damp mix, 10mm joints, pushed well into the joints, polished off with a jointing trowel

What you reckon and thanks once again

[Brucieboy]

I'm a DIY'er and this is brill site as you say. I'm currently pointing 50m2 of sandstone paving and using 3:1 building sand / cement. To get the right colour (plus me being a bit fussy), I'm using 50/50 Portland cement / white cement with a buff pigment along with a small amount of SBR. Mix all the dry powder and pigment first, then add this to the sand and mix thoroughly before adding any water (about a 15-20 kg batch in a wheelbarrow is fine until you get used to it) . Add the SBR to about a litre of water and start mixing with a shovel. Thoroughly mix, adding a bit more water as necessary to achieve a damp consistency. Press well into the joints and finish off after half an hour or so with a jointing tool.

Alternatively, depending on your budget, a lot of the guys on here use Easipoint mortar (different colours avaialble) applied via a special hand held squeeze gun. Much quicker, but more expensive.

[lutonlagerlout]

building sand bruce? ye gods ,dont let the gaffer read that!!

easipoint is by far the best pointing method

btw i am a guinness man myself but lutonguinnesslout downt have much of a ring to it does it?
LLL

[Brucieboy]

LLL - a bit confused?? The gaffer recommends washed building (aka soft) sand for jointing/pointing mortar. Definitely sharp sand for bedding.

[lutonlagerlout]

zut alors1
my mistake bruce
keep up the good work
LLL

[Brucieboy]

TLC - Met Office this morning said no sign of rain in my area today. Absolutely chucked it down for about 15 minutes this afternoon. Didn't have any polythene to cover the area I'd already pointed resulting in me having to remove sloppy mortar from about 3m2 of flags (plus the mess from the flags themselves). Took me about an hour to clean up. Motto - be prepared - and don't always rely on the weather forecast!! I'm learning the hard way.

[ilovesettsonmondays]

where abouts in essex are you brucie.lutonlambrinilout has a ring to it too tony ???

[Brucieboy]

ILSOM - Colchester area. See you're an Essex lad yourself.