Getting the levels right on a patio is a time-consuming and pain-staking job, but putting effort into it will give you a patio that looks good and drains well. The alternative is a patio where the flags don't line up correctly, there are height differences at the gaps that get bigger over time, and water forms puddles when it rains.
As with many other aspects of driveway laying, getting this right is more about the preparation of the supporting surfaces than the actual Laying Of The Stones, flags or other surfaces. No specialist equipment is needed and, although it is now possible to buy cheap laser levels, that's over-kill for just one patio.
What Does Level Really Mean?
There are three different elements to getting the patio levels right. The first is to make sure the area is flat; that is to say that there are no raised edges between stones to trip people up. The second is to make sure it is level, as in all the flags are lined up with each other in the horizontal plane.
And the third, although it seems contradictory, is to make sure the patio surface is not level. For Drainage Reasons you need to have a gradient, known in the trade as a 'fall', from one end of the patio to another. Usually this slope will go away from the house, so that water isn't encouraged to pool next to it and cause damp problems. But in order to be able to make a fall that is not level, you need to know where the level is.
Starting the Level from the House
Assuming the patio site has already been excavated and the edges marked out with pegs, pick a level on the wall of the house that is below your Damp-Proof Course, but not so low as to make too big a step coming out of the house. If your ground is on a steep slope, particularly if it slopes toward the house, then you will have to get creative at this point and perhaps decking would be a better choice than a patio (see When, Where And How To Fit Decking on this site)..
Using reasonably straight edges, such as new timber battens, and the longest spirit level you can lay your hands on, mark that line on the brickwork of the house all the way along with chalk or another semi-permanent marker.
Calculating the Patio Fall
It's now time to calculate the fall, which will encourage water away from the house, using the industry standard ratio of 1:80. This means that for every 80 units of distance along the patio, the level must drop by one unit. So if your patio is a rectangle 6 metres wide and runs 4 metres from the house, it will have to drop by 4m divided by 80, which is 5cm.
Now we know the patio has to drop by 5cm between the house and the end of the patio, but in a straight line. In order to measure this we need to transfer the level from the house to the 4m mark. This can be done by getting the longest straight edge piece of timber you have and attaching your spirit level to it. Set the end near the house on a pile of sand and a brick then do the same for the far end, tamping down the brick on the sand until the timber is level.
Taking the Level Out
The nearest peg can then be marked with a level and the 5cm drop. Continue this procedure along the wall of the house and then join the marks on the pegs with timber boards or lightweight string, perhaps edging boards tamped down into the soil, whichever method you prefer that suits the materials you will be laying. Use those markers as guides when you are laying the top surface of the patio, with straight edges to make sure the slabs line up in all the relevant directions.
This is a simple method which should deliver the goods for the average patio and doesn’t need any specialist equipment. With care it should be good enough to ensure a smooth surface without puddles which won't trip the unwary.
DRIVEWAY EXPERT IS FOR SALE:
This website is for sale [more info].
Hi I want to lay approx 70ms of patio, the issue I have is that the patio wraps around my conservatory,and meets up with my back door approx 10m away, how do I get the fall right when its running around the conservatory for it to meet the back door without the fall going way below the damp course, I hope that makes sense?
Tezzer - 30-Apr-20 @ 2:25 PM
Help! My builder recommended a fall of 1:100 for the patio (which is about 10m x 6m).
Last week he asked me to "accept the risk" of laying at this fall since the manufacturer of our slabs recommends 1:60(they are fairly smooth limestone, well rectified, which wasthe reason the builder gave for1:100 being ok. I was aware 1:80 is more usual).
It islate to change the falls (he's installed block and beam and end wall for patio). It is 6 feet above garden level as house is on a slope.
What is the risk I'm being asked to accept? Since it was his design I don't think I should accept it but he is saying if I don't he won't lay the slabs. And any other layer would be left with the built-in fall he has planned in any case, so I'd still have to "accept the risk" I think.
Mashie - 8-Aug-19 @ 10:18 AM
Hi i have a front garden roughly around 90 square metres I would like to lay down block pavers with a fall from the house to the road however the pavement is around 30cms higher than where i would like to start from. What can i do about this?
KF - 1-Oct-18 @ 11:30 PM
Hi
I have to lay a fairly large (120m2) L-shaped patio and I want it to be at, or very near, threshold level with 3 sliding patio doors - two running N-S and one between then running E-W so to speak (the house is L-shaped as well.
With these requirements, it is difficult to see how to give the patio fall without it spoiling the line along one or other threshold or having diagonal slab cuts. I can lay a linear drain along the house wall but would this be enough if the patio was laid without a fall. I also thought about laying on sand without grout (like block paving) so that it was permeable; would this be a better plan?
Any advice gratefully accepted.
Phil - 23-Apr-18 @ 3:38 PM
Alfie- Your Question:
I have had two patios lays with porcelain paving. They are both about 4.5 metres square running from the house to the brick garden wall. When it rains the water doesn’t go past the grout abc the flags only dry about 12 plus hours after it’s stopped raining. I had the garden designed and then an expert do the work. The fall across the whole patio is about 2 cms. The gardener says that’s right. Is it?
Our Response:
The industry standard ratio is 1:80 i.efor every 80 units of distance along the patio, the level must drop by one unit. Your patio is 450cm from your house, so the drop should be about 5.6cm
DrivewayExpert - 9-Apr-18 @ 12:37 PM
I have had two patios lays with porcelain paving . They are both about 4.5 metres square running from the house to the brick garden wall. When it rains the water doesn’t go past the grout abc the flags only dry about 12 plus hours after it’s stopped raining. I had the garden designed and then an expert do the work. The fall across the whole patio is about 2 cms. The gardener says that’s right . Is it?
Alfie - 7-Apr-18 @ 3:41 PM
Our patio is 3.8 mtrs wide and the widest part . Our fencer commented today about the patio that it needs ripping up as he said the fall is too steep. We asked our builderif it need be this steep and he said that it does. We have measured where we could with a spirit level and the gradient is atleast 10cm and this is only using a 5 foot level. If we put table and chairs on they would no be level.
. - 24-May-17 @ 9:58 PM
When it rains heavily water pools on my paving. The slabs are flush with the backdoor and the water seeps in. Has the paving been incorrectly laid by the builders and if so i can I tell?
Buster Gonad Re: Planning Permission for Driveways
Hi, I have a disturbingly large lump on my left tezzy, will I need permission to remove it by closing my car door hard on it?
Don Re: Planning Permission for Driveways
Hi, I have a driveway behind my house which leads to a garage.
I have recently put a driveway infront of my house and…
24 March 2021
Jim Re: Planning Permission for Driveways
Hi i live in a cul-dey-sac and im looking at making my front garden into a drive but i will have to come over the grass…
Lizzlelog Re: Planning Permission for Driveways
Hi looking at buying a house in Wanstead conservation area. House looking at has a drive that has been in place pre 1996.…
Re: Planning Permission for Driveways
Hi, I have a disturbingly large lump on my left tezzy, will I need permission to remove it by closing my car door hard on it?
Re: Your Property Boundary: What You Need to Know
Hi, we have recently obtained our land registry deeds showing the boundary between us and our neighbour.…
Re: Your Property Boundary: What You Need to Know
Hi, we have recently received our deeds to our house showing the boundary between us and our neighbour. When…
Re: Your Property Boundary: What You Need to Know
Hi, we have lived in our home for 17 years and have recently got the deeds to our property showing our…
Re: Your Property Boundary: What You Need to Know
Hi, we have been in our house for 17 years and there was already a boundary fence and a tree on our…
Re: Planning Permission for Driveways
Hi, I have a driveway behind my house which leads to a garage. I have recently put a driveway infront of my house and…
Re: Planning Permission for Driveways
Hi i live in a cul-dey-sac and im looking at making my front garden into a drive but i will have to come over the grass…
Re: Environmental Issues When Constructing A Driveway
The owners of the middle houses in a block of four have both had sealed drivewaysinstalled, adjoining…
Re: Environmental Issues When Constructing A Driveway
The owners of the middle houses in a block of four have both had sealed driveways installed, adjoining…
Re: Planning Permission for Driveways
Hi looking at buying a house in Wanstead conservation area. House looking at has a drive that has been in place pre 1996.…