If you have followed these guidance notes in the correct order, your patio should all be dug out and prepared ready for the base material. If it is not, go back to the area Preperations and go through the items as instructed.
Right .... ready for some more work? This is one of those areas that will either make your visitors say in astonishment "...you done it yourself ! " - or " ... you should have got a professional in ...". The key to all the sections on the diy part of this site all have one main big overiding rule ... Take Your Time, Don't Rush It !
Most Patios that are laid today tend to be of 'slab' type. That is, a man made or natural stone square or rectangular shaped pre-formed concrete and aggregate stone tile. Although you can also get hexagonal, circular, oblongs - infact almost any shaped slab, I am not splitting hairs here and will be allowing for the normal square 18"x18" slab.
When laying this type of slab you do need a proper base underneath them. I have seen these slabs laid straight onto soil and sand but they never stay put and are more liable to damage as the weather can easily get under them (frost etc). We shall be laying down a base and then using a mortar mix to 'stick' them down so they don't move. Details on other types is at the foot of this page in brief.
I am also assuming here that your stakes are still in place and are all at the same levels you left them at - that is, the tops of the line of stakes nearest the house should be 6" below the damp course of the house. Give them all a quick check to make sure they are all ok and have not been kicked by anyone - if any are wrong at this stage, it could throw out all your patios levels, so it's quite important to double check every stake.
Your stakes tops against the house should be a brick and a half (6") below your house damp course level. The next line out from the house should be a touch lower to allow water run-off. I keep repeating all this as it is important.
Get yourself a tape measure and a nice thick felt tip pen - a permanent marker may be best to stop any rain washing it away ! Right, Measure the thickness of your chosen patio slab - lets say it's an inch for tutorial purposes. Measure down from the top of every stake one inch and draw a line all around the stake - and on all stakes. This now shows you the thickness of your slabs clearly marked on all stakes and can be seen wherever you stand as you have marked every stake all the way around on four sides. We now have to put a mark on the stakes showing where our cement / mortar mix will be, so, measure down from the line you have just made another inch and a half - draw the lines all round as before. You now have two lines on every stake. The distance from this second line to the excavated soil level should be about four inches, if it is more you need to fill the area with soil to build it up - if it is less, you have some more digging to do !
Assuming you do now have four inches from the bottom line on the stake to the ground, that's it, the area is prepared, just make sure that the soil is not too soft in places and walk over the area to firm up a bit. We are now ready for the base material to go into the area. Just to be sure, below is a simple lined graphic to show what you should have. The graphic below that shows the stake (in red), with the lines and what they are meant to line up with.
The base material is known as 'Type 1 mot' and is used under motorways - so it should be good enough for your patio. Again, tell the builder centre the area you wish to cover and the depth (4") you want to fill, they will work it out for you and arrange delivery etc with you.
It would be very handy again here to have a mate or two to help on the day it's being delivered. You are going to be using your nice clean wheel barrows that you washed out after doing all that cement work, and those sheets of hardboard will be used again to protect your drive.
There's not much skill involved in this next bit really ... just start barrowing in the base starting at the farthest end of the patio, and fill the area about half an inch over the second line - we want this bang on this line, but it will be settled. Continue the process by barrowing some in and then raking it out so each stake has just had it's second line down partially covered by about half an inch. Do not try to barrow it all in and then try to rake it out - you will end up with lots of high spots and lots of low spots and a long time trying to get it right - do it as-you-go, it's much easier. If you are half a barrow short, do the 'dig-a-hole' trick we did with the wet mix when making the base - but in an area you are less likely to walk incase you over-do it !
The lorry has gone and so have your mates, your left to sweep up out front and ponder what's next? ... Now you need to compact all this farly loose stone down to a more solid structure that is going to take the full weight of a few tonnes of cement and slabs and anyone else's weight that will walk upon it. You now need a 'Vibrating Plate' or 'Whacker Plate' - don't go too big, the smaller the better, unless your patio is quite large.
Like all hired items - as you are no-doubt aware, you will need to produce some I.D. and a healthy deposit to ensure you are not going to do a runner with their machine. You will only need the machine for an hour, but it is heavy, so, unless you have a van (and a mate again), get the item delived and picked up again - you will be charged extra for this though.
Start the machine and hold on ! It will have a mind of it's own and will just want to keep going forwards - you will just have to steer and not let it bash into your house. Go over the area about three times in a circular motion, starting on the outside and working your way to the middle. Avoid the stakes - this is the hardest bit of the compacting. As you walk behind the machine you will notice the difference that is has done, what was loose stones has now become a much more solid structure. Before returning the machine, go all over the area with your eye making sure you can now see the guide line - the second one down on the stakes - to check you can now see all the lines. A claw hammer and a pice of the old shuttering timber from the concrete base together with a club hammer will sort out the areas the machine could not get to ie; corners and close up next to all stakes. If an area looks a little high, rake it into a lower area and repeat all over the area, using the machine for one last pass to re-compact any areas you had to soften and rake etc. Send the machine back - you have now completed the base for your patio.
I would ask you to consider not going for the cheapest slabs at the local diy store. These do not only look horrid, they are also very slippery when wet and due to the thin nature of the slabs, will break apart at the sight of the first heavy frost. If you are doing all this to sell your house - go ahead, but if you are going to be living with them for a fair while, go for something a bit more descent. Any Landscaper will reccommend their fav slab - and all will be different. My reccommendation would be for a slab currently held in the 'Marshall's' range - I have used these for many years without problems. The choice is yours.
When the slabs are down and all is finished, they are strong and robust. But from the yard to your garden is a delicate time. They must not be stood on their corners - they may chip, they must not be thrown into a barrow - they will mark and have edge damage, and they must not be just all piled up on top of each other - the bottom one's may break under the weight. Use some of those timber battons and lay two on a flat area of soil close to the patio base, but not on it. Stack your slabs on these battons no higher than your waist - treat as egg's - they are fragile. When delivered, do check the pallet for any damage or breakages - the depot will refund you or give you replacements free of charge, but if they just drop and you sign, finding damage later is your fault and your cost !
Still got that mixer? Set it up again close to the patio but not on it, and the same for your sharp sand and cement. You should have a nice clean patio base with mixer, slabs and cement all off the base with ample gaps between to walk about as you work. Decide where to put your sharp sand for the mix - next to the mixer is a good idea, but don't have the mixer next to the slabs incase it splashes and spoils your nice clean pile.
I am one for good strong mixes when I lay a patio. Again, others will tell you different. I use a mix of one and a half of cement to ten of sand. The mix should have all the sand in first, then the cement, let it mix and don't add any water just yet - incase the sand is already soaking wet from recent rain etc. The mix here is quite important and nothing like the mix you did for the concrete base. This mix must not be wet - but not dry neither. A rule of thumb here is if you can take out a handfull of the mix and make a snowball out of it and it stays together without crumbling or dripping out of your hands - the mix is right. Don't let the mixer whine away for over 20 minutes or it will start to make marbles of cement - this is useless for laying slabs upon.
So, you now have a mix on the go and are ready to lay your very first slab.
The first line of slabs you lay are the most important. Every other slab you lay after this first line will be following off of the edge of these one's so again - Don't rush it, take your time.
Assuming that the line of your house is at right angles to your fence or wall, if it is not, always go from the house line - any cuts you have to do will be made against the fence. Get yourself a couple of those battons and put them together so they are about two inches thick, put this against the wall of your house and another two the same thickness against the fence or wall. We are working at the corner of the patio against the house and away from your barrow / walkway area (so you can still get you and materials in and out), and you now have your battons against the house and the fence / wall etc. These battons are here as a precaution incase the patio skewes off a fraction and ensures you have a little flexibility as you go along.
You will have a two inch gap between the house and a slab that will be filled in later on.
The mix into the barrow, and the mix is right (remember the snowball?). Get your mate to do you another mix when you want, depending on the speed you lay the slabs. With a shovel, put the mix on the base in the corner we are working in - don't spread it all out everywhere as you have to stand close to where you are laying and the whole area will soon be very messy. Remember the other lines on the stakes? The mix should go down so it comes up to the first line on the stake - this means you are putting the mix down about an inch and a half thick. Use a rake to get it flat a little larger than the size of a slab. Now get yourself a small potting up type hand spade or a small trowel. Use the trowel to take a small amount (about a coffee cup full) and put this on top of your raked out area, but put it in five areas. Imagine looking down on the slab - it's square right! we want one trowels worth to each corner and one in the centre - not on the slab itself, but on the raked out area you have done. The slab is then laid upon these five small mounds and is now ready to be set in. Now comes the tricky part ....
Get yourself a large rubber mallet. A camping shop will sell you one unless your diy store does not. With this rubber mallet and your spirit level you gently tap the centre ONLY of the slab to set it at the right height - the top of the slab should be the same height now as the stakes tops, so these stakes are now invaluable as an at-a-glance guide as you are going along. If you have a slab that needs to go down on just one edge or corner - do not bang that corner or edge down ! it is very tempting, but if you do, you will lift the opposite corner or edge out of the mix and when it all dries - you will have a 'wobbler' - we don't want any of these !
If the slab needs to go down at one end, imagine a ring the size of a small side plate (6") drawn in the centre of your slab, now only ever hit the hammer on the slab on this ring or in the middle of it - never outside it or here come the wobblers ! If the slab needs to go down by a fair amount (more than an inch), remove the slab, remove some of the mix from under, redo your five mounds and re-lay the slab. The first few you do will seem to take forever, but after a few, you will get the hang of it and speed up.
Remember when making your five mounds, to always use exactly the same amount to each mound or you will forever be lifting the slabs and removing excess mix etc - all this is assuming that your first plonked down mix that is raked out is infact quite level.
After all your mucking about with this first slab, be sure to check how it lays with the spirit level. It should be falling very slightly away from the house (water away), yet dead level across the house line. When satisfied gently tap a little mix around all edges to make sure there are no voids / holes etc then lay the mix and rake out to the stake line for the slab next to it. Be sure that the edges of both slabs do not even have a few grains of sand on them, this will stop you butting them up close to each other and will show and start to make all the patio lines run out.
When your five mounds are in place for the second slab, and the edges are clean carefully lay the second slab, not corner down on the floor and lay - this will make wobblers, try to place the slab straight down equally all round, so all of the bottom of the slab touches the mix at the same time. The edge of the slab should almost scissor against the first slab you laid. With just a thumb applying gentre pressure to keep this second slab against the first, gently hit that invisible six inch ring in the centre of the slab to set it down - keep looking at the wooden stakes and the height of the first slab as you tap, don't get carried away, small gentle taps are much better than a few big'uns.
The idea behind using five seperate mounds to set the slabs upon is quite simple. Because there are five seperate small mounds, there are also gaps between each one as well - setting the slab upon these mounds makes the mix spread out underneath the slab and all the mix touches each other to make just one big area. If you just made it all flat at the right height and laid your slab upon this, you would have no way of setting the slab down by tapping as it's already at the right level, and if you just sat it on an area without tapping it down, the surface of the mix under the slab would dry like honeycombe and would allow pockets where water could get in as well as worms - that bring in soil - that comes through the gaps - that then grows weeds ... see where I am coming from?
As the second slab is almost in place, check with the spirit level running over both slabs, look for a gap under the level, if you see one, look at your slabs and set as neccessary. When the level sits on these two slabs withour rocking, and there are no gaps under the level - great. Now check it the other way, are you still getting that gentle fall away from the house - make sure you are or you will have puddles on your new patio when it rains. With the second in place gently make sure there is mix under the edges. Repeat this procedure to get that first line in along the house.
If you have a drain against the house from the sink or upstairs bathroom / toilet, and you need to lay a slab here, leave it till last, lay full slabs as you go leaving your gaps where drains, rodding points and other obstructions mean you cannot lay a full slab. Make sure the area for the eventual cut slab is cleared of all cement - if it goes hard you will have to chisel it all out so you can lay in your cuts - it's easier to remove wet mix with your trowel rather than a hammer and chisel. Be sure the slab edges are clean as well !
If you had a great big rusty old steel manhole cover right in the middle of your patio, you can buy a recessed new cover that would be set so it's top would be the finished height of the patio. This would then have slabs cut-into-it at the end of the job.
After you have laid three slabs, go back to the first you laid and just check that all the bashing you have been doing to slab number three has not moved slabs one and two. They can move about a millimetre on each bang if you apply too much sideways pressure when ensuring a tight fit between slabs. If they need to be slightly adjusted with slight taps - now's the time to do it. If you lay more than three, you may not be able to move the first and here would come cock-up number eight !
Cement is nasty stuff and if you have not a pair of those rubberised gloves - get some. You may not notice anything for a few hours but after a day, your skin will crack and dry out, and if your a nail-biter it's going to hurt a lot. Try to wipe the gloves on your trousers before you lift slabs about. Cement will stick to the ends of the gloves and you will be transferring lots of little dots on the top (visible) part of the slabs. Get a soft brush and keep these tops clean as you go. If the mix was too wet, you will never get rid of these marks. Keep the mix dry (snowballs!), and keep it all clean as you go.
Tempting as it may be, don't walk on the freshly laid slabs - infact don't even lean on them, if you do, you may set them lower in the mix then ... here come the wobblers and the puddles again !
Leaving it for a day or two ?
Maybe you wont get it all laid in a day. Even though your mate is still around (better put him on your christmas list). So how do you decide how to finish it for a day?
Bearing in mind you need to place the first slab on your second day tight against one that has set, there should be no cement mix at all on the floor or against the edges of all laid slabs. Get the trowel and cut straight down the edges of all slabs and wipe it all away. Spread out any excess cement mix thinly over the base - about half inch thick is fine. Wipe the edge of all laid slabs to be sure there are no sand or cement grains on them that will obviosly harden overnight. And remember that sheet you used to cover that concrete base? Just spread this out over the laid area and gently lay the sovel, the level and other small hand tools on the sheet to stop the wind taking it away. Again, we are just doing this as a precaution incase of rain etc. Naturally, you must wash all the mixer and the tools that touched the wet mix. The dustbin full of water again does the trick. - Don't forget to ensure the slab tops are clean.
Day 2, 3 , 4 ....
It would be very tempting to just write "...see above" or "..repeat as above", but althogh true, you must remember that your stake tops are running away from the house level-wise to ensure that any water on the patio will run away from the house. As subsequent slabs are laid, you must keep checking this fact. I repeat again - be fussy and take your time.
Continue laying your slabs using the technique you should now have developed. As you have been laying the slabs you would have been either removing or banging down the stakes as you get to them so you can lay the next slab. It does not hurt to bang them down, if this is easier - it will not harm the patio, just make sure the stake tops are at least at the base level - nice and low. As you may not be used to this type of work, your muscles may be telling you the same - so get yourself one of those wide belts that resemble a weight trainers belt, but get one made from neoprene. These neoprene one's fit tight and keep the lower back warm - that increases blood flow and eases the aches, as well as support to the area as you work. These types are not gimmicks - they work. Before this turns into a 'Dr. Easyscapes' page - we get on with the task.
Continue as before. Keep them clean, don't hit a corner or an edge and watch those stakes and the bubble in the spirit level. By the end of day two - certainly day three, you should have laid your last full slab. When you have laid the line of slabs nearest the grass, keeping your trowel wet, run it a few times along the wet mix under the slabs to finish off to a more sealed finish, this will help repel too much wet from the grass area once all done. The cement mix should virtually go straight down to allow for soil to come right up to the patio - or grass may die if soil cannot be tight against the slabs. Although cement is quite porous, this action just finishes off the area better.
This is where you have to be very very careful ! The hand tool required for this usually comes with a transformer or can be petrol driven, is quite heavy and awkward to handle and is simply called a stone cutter. It can be an awkward tool to use if you are not used to it - observe all the safety issues given with the tool from the hire shop and stick to them. You can get (for extra cash) a machine that stands on legs, has a water tray in it and is much safer to use than the hand held machine. This type would be best suited and safer.
The Dry Cutter - Be Careful !
The Wet Cutter - Tool for the Job
Slabs are marked so if you are going around a drain, don't cut the slab so it's a tight fit against the drain - leave the thickness of a batten (about an inch) so when the slab is laid, it gives you room for your fingers to move the bit about, and it will match the two inch gap you left along the house as well. A carpenters pencil and a piece of straight batten will do for the marking out. If you did have some damaged slabs left in the pile, use these and arrange so you cut off the damage as you use them up. It may be an idea to look at all your cuts you have to do and to lay out the remaining slabs looking at their damage to see what one goes where best.
Let's say you have a slab and you need to cut a square out of one corner to make the 'l-shaped' bit that's left fit in your patio. Be sure the slab is laid down flat with the top side up showing the cut lines. There is a point on the slab where the two lines meet, this needs to be cut so it's a perfect sharp corner with no 'overcur' scars showing along the edge of this slab.
Cut along one line toward the point where the lines meet. Do not cut right into the other line stop short by a quarter of an inch - repeat on the other line, and make sure the slab is cut all the way through. Carefully lay the slab across a batton on the ground and just tap it with the ball part of your lower palm (or fist if your a man), the square should break away easily. You notice that the corner is not quite sharp nor is it quite far enough - we designed it this way. If you have access to a small grinder with a three or four inch wheel, put a stone cutting disk on it (only a few pounds) and carefully finish off the corner to give a nice, sharp corner. When this slab is set in, this corner makes all the difference between a dodgy quick rushed cut that shows scars you will always see, and a perfect job. Be sure not to bang this slab or any cut slab as hard as you have all the others - it is now a little weaker and it will break much more easily.
The most fiddely cuts are those that would have a notch cut along one edge, like a square but in the middle of a slab - or a cut that tapers off to a point. The notched one's are done much the same way as the one mentioned - dont cut all the way, knock out the bit a fine finish with the samll grinder. The one's that taper off to a point are a bit more tricky. Best is to trap the slab you want to cut between two other slabs and then cut - this gives a bit more support to the tiny sharp tapered end. Never bang these one's down - try to get the mix virtually bang on and if you must tap it, do it with the bare hand, even then, avoiding the sharp end.
Once all your cuts are laid in, try to leave the job for a day or so and allow to go off. You may have forgot what slabs were cuts and what is not and start upsetting them by walking on them trying to do the rest of the job.
This patio has had the slabs butted tight up to each other with no cement between each slab. If the type of slab you have chosen does not butt up tight as mentioned, you have a lot more work laying the patio, as you would have to leave a half inch gap around every slab - this gap needs to be filled in, and it's a lot of work. Be sure to ask when ordering if your slab is a butt finish or is pointing required?
You have to fill in the remaining gaps in your patio. This is mainly the two inch one left along the house, and the smaller one inch one's around all your cuts. Your mix should be the same as you used to lay the slabs, but can be a bit dryer. You are at risk of now making that nice clean slabbed edge all along the house run very dirty and it may show up when the job is done. Get some hardboard again with it's factory finished straight edge running right along the edge of the slabs - all you can see is the bit you need to fill, all the slabs are covered.
Use your trowel to put the mix in the hole, pushing it down as you go. When you have done along about three slabs, get a piece of the batton - a clean bit, and keeping it flat on the hardboard drag along - this evens it all out on the top just right, you can then do a similar action with the trowel. Don't worry too much about the finish at this stage, just make sure there are no holes, low or high areas. When all the run is done, remove the hardboard and very very gently run a soft brush along the freshly laid mix to add a texture - this texture will look ok when dry, helps to hide any imperfections you may have left in and cleans the edge at the same time. But remember what happens to a cement based mix when you play about with it too much? Remember the concrete base? Water will rise to the top if you keep playing with it. If you have not achieved your desired brushed effect within three strokes - leave it alone or the water will rise and you will spread watery cement all over the slabs. You can always go back to an area after half an hour or so to finish it off when dryer.
The very last job is a theraputic one ! Although the slabs are butted tight together, there is still a slight gap between them of just a couple of millimetres. Provided the patio is dry (the surface I mean, not the cement), buy a bag of 'Kiln Dried Sand' - this sand, as the name suggests, has been through an oven and been totally dried - this makes it like the sand in an egg timer, very fine and goes in small gaps. Just one small bag of this goes a long way. Empty all over the patio and move around slowly with a soft broom. The sand will fill all the gaps. You will see the sand dissapearing down the gaps - just keep moving the sand about with the broom until the gaps take no more.
*If the patio had lots of cement bits and other debris on it, it would be a good idea to sweep all this away before doing the sand thing - or you will be mixing the sand with all the debris and you wont get the same result.
Sweep away any excess sand from the slabs onto the eventual grass area, it wont hurt the grass / soil under.
The methods adopted to lay different types of patios varies slightly depending on the type. The block paving blocks are not laid down onto a mortar mix, these are laid onto sand, but the base under is still required and the amount of excavation depth with also differ. A wooden framework around a block paved job is used as a guide to pull the sand to the desired contours and the bricks then laid within. Block paving needs all it's framework (the outer rows of blocks), to be cemented as these hold everything in place - and the sand is used to bond it all together and to stop individual blocks from moving about.
Hexagonal, circular, circle kits, cobbles, and even crazy paving will all need a base and to be laid as detailed above. Just be sure to check if the slabs are tight butted or require that pointing / grouting / annoying gap in between each and every slab. Some Landscapers use a very dry mix and sweep the grouting in between the slabs - this leads to a non sealed finish that tends to 'honeycombe' and therefore fail within a year or two, therefore not reccommended by me on these pages. There are applications where this type of pointing would go, but not here, and not on this type.
This now ends the tutorial on the Patio:
And by the way ...
You have just laid your first complete Patio.
Had your rest? Are you ready for The Lawn ?