DIY GUIDE · GARDEN & OUTDOOR · CHECKED OCTOBER 2026
How to lay a patio yourself
Two to three weekends for a 4 × 3 m patio. €980–€1,420 in materials and tools.
Setting out, depth and fall, the sub-base, bedding and jointing, safe cutting, and where it stops.
- Every step, start to finish
- Checked October 2026 — sources at the end
- Honest about when to call a pro
FIRST, THE HONEST ANSWER
Do it yourself, or get a gardener?
Do it yourself if…
- The patio is at ground level on firm, reasonably level ground, to the rear of the house
- You can dig the area out by hand and move several tonnes of soil and stone over a few days
- You can keep the finished surface well below the damp-proof course of the house and falling away from it
- No drains, manholes, gullies or services need moving or raising
Get a pro if…
- The site slopes enough that one side needs a retaining wall or steps
- The patio would sit against the house with no room to keep below the damp-proof course
- Drains, inspection chambers or gullies are in the area and would need raising or diverting
- It is at the front of the house for parking, or the ground level changes by a large amount
Safety first
- Do not dry-cut concrete or stone with an angle grinder. The HSA warns that cutting concrete, blocks and paving releases respirable crystalline silica, which can cause silicosis and cancer; use a block splitter where you can, or a saw with water suppression or on-tool extraction, and a well-fitted FFP3 mask.
- Wet mortar and cement burn skin. Wear waterproof gloves, long sleeves and eye protection when mixing and laying, and wash cement off skin at once.
- Flags and bags are heavy. The HSA's manual handling guidance is to avoid lifting from the ground with a twist; get help with large flags, use a barrow, and carry bags close to your body.
- Find out where drains, water pipes and cables run before you dig; never dig blind near the house wall.
- Wear steel-toe boots, ear protection with a compactor or saw, and keep children out of the work area.
- Hire a plate compactor only with its operating instructions, and never run a petrol one in an enclosed space.
Stop here: Raised ground, retaining edges, and anything the house relies on
Under the Planning and Development Regulations 2001, Schedule 2, Class 6, a hard surface to the rear of a house for use with the house is exempted development, and landscaping is exempt only where it raises or lowers the ground by no more than 1 metre compared with the ground next to it. A hard surface to the front for parking has its own conditions, and a planning condition on your estate or a protected structure can remove the exemption. Raising ground against the house wall bridges the damp-proof course and risks damp, and retaining a change in level is a danger if done wrongly; both are work for a professional. How to hire a patio layer →
| MATERIAL | COVERAGE | FOR THIS JOB |
|---|---|---|
| Paving flags | 400 × 400 mm concrete flags are 6.25 to the square metre | Area plus spare for cuts |
| Sub-base stone | Compactable crushed stone, compacted 150 mm deep or more | About 0.15 m³ per m² at 150 mm |
| Sharp sand and cement for the bedding mortar | Mixed about 6 parts sharp sand to 1 part cement | A full bed under every flag |
| Jointing mortar or jointing sand | 3 parts soft sand to 1 part cement, or kiln-dried jointing sand | Jointing sand covers 7–10 m² per 25 kg bag |
| Edging kerbs or edge restraint | Laid on a concrete bed | The length of every open edge |
How much you need
Flags = area × flags per m², plus a few spare. Sub-base volume = area × compacted depth. For a 4 m × 3 m patio of 400 × 400 mm flags: 12 m² × 6.25 = 75 flags plus about 5 spare; sub-base at 150 mm = 12 × 0.15 = 1.8 m³ of stone.
Order a little more sub-base than the volume, because loose stone compacts down. Ask the merchant to convert cubic metres to tonnes for the stone you buy.
Concrete flags are the cheapest, the most even in thickness and the easiest to lay. Block paving is laid dry on grit sand and compacted, and suits curves and drives. Natural stone such as granite or sandstone looks best but varies in thickness and must be laid on a full bed of mortar.
The sub-base is the load-bearing layer. Use a graded, compactable crushed stone, often sold as Clause 804, not rubble or topsoil. The manufacturer's guidance for most domestic paving is a compacted depth of 150 mm to 300 mm depending on the soil and the use.
Flags and natural stone go on a full bed of mortar that supports the whole flag, not five dabs at the corners. Block paving goes on a screeded layer of grit sand and is compacted into it. Check which the product you are buying needs.
Mortared joints are traditional for flags. Kiln-dried jointing sand brushed in suits block paving and some open-jointed flags. Brush-in jointing compounds are easiest for an amateur, but read the weather limits on the tub.
Paving made from natural aggregates varies in colour batch to batch. Mix flags from at least three packs as you lay so colour bands do not show, and buy a few spare for cuts and future repairs.
THE PART THAT DECIDES THE FINISH
Before you start — by the ground you have
The ground under the patio decides how deep you dig and how you build up. Find yours and do its checks first.
A lawn or flat garden ground
Turf or soil, roughly level, firm underfoot.
- Lift the turf and stack it to reuse elsewhere
- Dig out all topsoil until you reach firm subsoil
- Remove any roots, soft spots or organic matter and fill them with compacted stone
- Check the depth against the house's damp-proof course before going further
Ground next to the house
The patio will run up to an external wall.
- Find the damp-proof course, usually a line in the mortar or a strip of membrane two or three courses above the ground
- Set the finished patio at least 150 mm below it
- Make the fall run away from the house, never towards it
- Do not cover or block air bricks or vents; if you cannot avoid them, stop
An old concrete or paved area
Existing slabs or concrete you want to replace or lay over.
- Break out loose or cracked slabs and check what is underneath
- Lay over solid, sound concrete only if the levels against the house still work
- Never raise the level against the house over the damp-proof course
- Separate rubble from soil for disposal
Soft, wet or clay ground
Ground that holds water, or that you sink into.
- Dig deeper and use a thicker sub-base, towards the deeper end of the manufacturer's range
- Consider a geotextile membrane under the sub-base
- Make sure the fall leads water somewhere it can soak away or drain
- If water stands in the hole after rain, get drainage advice before you lay
A sloping site
Ground that falls more than a gentle slope across the patio area.
- Measure the drop across the area with a string line and a level
- A small slope can be taken out in the depth of the sub-base
- A bigger slope needs a retaining edge or a step; that is beyond a patio job
- Do not build a raised patio against a boundary wall or fence
THE JOB
The steps, in order
Set out the area and the levels
2–3 hoursStart with the checks above for your ground. Dry-lay the flags on the lawn to confirm the layout and count. Then drive pegs at the corners and run string lines to mark the edges, checking the corners are square by measuring the diagonals, which must be equal. Mark the finished level on a peg against the house, at least 150 mm below the damp-proof course. Set the far pegs lower to give a fall away from the house of about 1 in 60, so a 3 m wide patio falls about 50 mm.
- Leave the pegs in place all through the job as your level reference
- Measure from the house wall, not from the fence
- Plan to whole flags to keep cuts to a minimum
Mistake to avoid: Setting the patio level with the back door and pushing ground water against the house wall.
Dig out to the right depth
1–2 daysDig the whole area out to the depth of the sub-base plus the bedding layer plus the flag, measured down from the string lines, so the dig follows the fall. Remove all topsoil, roots and soft spots. Keep the bottom of the dig firm and roughly even; do not dig too deep and backfill with loose soil. Stack the soil for disposal or use elsewhere.
- Check the depth every metre with a tape from the string
- Dig in dry weather if you can; wet clay is heavy and slippery
- Keep spoil off the lawn on boards or a sheet
Mistake to avoid: Digging too shallow and finding the finished patio sits up against the damp-proof course.
Lay the edge restraints
Half a dayWherever the patio has an open edge against grass or a bed, lay a kerb or edging on a bed of concrete, with concrete haunched up behind it, so the paving cannot spread. Set the kerbs to the string lines and the fall. Leave the concrete to harden before you compact or lay against the kerbs; compacting next to green concrete knocks them out of line.
- Edges against a wall or an existing path do not need a kerb
- Check the kerbs with the level as you set each one
- Keep the cut face of any flag away from the edge restraint
Mistake to avoid: Leaving the edges unrestrained and watching the outer flags creep and rock within a year.
Build and compact the sub-base
Half a daySpread the sub-base stone in layers, no thicker than your compactor can handle in one go, and run the plate compactor over each layer several times before adding the next. Build the fall into the sub-base itself, checking it with the string lines and a level on a straight timber. The finished, compacted sub-base should come to within a few millimetres of its target level everywhere; it is what the paving will mirror.
- Dampen dry stone slightly; it compacts better
- Run the compactor in overlapping passes, edges first
- Fill any dips with stone and compact again rather than making up with sand
Mistake to avoid: Laying the sub-base in one deep layer and compacting only the top, so the patio settles in hollows.
Mix the bedding mortar
30 minFor flags, mix the bedding mortar of about 6 parts sharp sand to 1 part cement, in a mixer or on a board, with just enough water to make it damp and workable, not runny. Mix only as much as you can lay in an hour or so. For block paving, skip this step: screed a layer of grit sand instead, to the depth the supplier gives, and do not walk on it once screeded.
- Mix in the shade on a hot day; mortar stiffens fast
- Keep cement bags off the ground and covered
- Wear gloves and eye protection; wet mortar burns
Mistake to avoid: Making the mortar sloppy so the flags sink unevenly and stain from the excess water.
Lay the flags
1–2 daysStart at a fixed corner, against the house or a kerb, and work outwards. Spread mortar over an area a little bigger than one flag, thick enough to tap the flag down to level. Lower the flag in place without catching its corners. Tap it down with the rubber mallet, working round the flag at points between the centre and each corner, until it sits at the string line with the fall. Check it with the level, set the joint gap with spacers, and lay the next. Mix flags from at least three packs as you go.
- Bed every flag on a full bed, never on dabs at the corners
- Check the level across several flags every few minutes
- Lift and rebed a flag that rocks rather than packing under one corner
Mistake to avoid: Laying on five dabs of mortar and leaving hollows that crack the flags and let water under.
Make the cuts safely
1–3 hoursMark the cut with a pencil and a square. Use a block splitter for straight cuts where you can; it makes no dust. For other cuts, use a hired saw with water suppression or on-tool extraction, wear an FFP3 mask, glasses and ear protection, and cut outdoors with others well away. Do not use pieces smaller than about a quarter of a flag at an edge, which break; adjust the layout to avoid them.
- Wash slurry off a wet-cut flag at once before it dries on the face
- Cut all the pieces for one edge at once
- Keep the saw's water supply topped up
Mistake to avoid: Dry-cutting flags with an angle grinder in a cloud of silica dust.
Leave it to set, then joint it
24 hours, then half a dayKeep off the patio for about a day so the bedding mortar can harden. Then joint it. For mortared joints, mix about 3 parts soft building sand to 1 part cement, damp, not wet, and press it into each joint with a pointing trowel, smoothing it off and keeping it off the face of the flags. For jointing sand, brush the dry kiln-dried sand into dry joints until they are full. Sweep off the excess before it marks.
- Joint in dry weather and cover if rain threatens
- Scrape off mortar crumbs once they have stiffened, not while wet
- Top up jointing sand after a few weeks as it settles
Mistake to avoid: Pointing in the rain and washing cement stains across the new flags.
Clean down and keep off
1 hourOnce the joints have hardened, sweep the patio thoroughly. Keep furniture and heavy traffic off it for a few days while the mortar gains strength. Check the fall with a bucket of water: it should run off towards the edge away from the house with no puddles.
- Do not pressure-wash a new patio; it blasts the joints out
- Cover the patio from frost for the first nights if it turns cold
- Keep the spare flags for repairs
Mistake to avoid: Putting the barbecue and table on it the same evening and rocking the new flags loose.
The mistakes that cost the most
- Finishing the patio too high against the house, over or near the damp-proof course
- A fall towards the house, or no fall at all
- A thin or uncompacted sub-base that lets the flags settle and rock
- Dry-cutting with a grinder and breathing in silica dust
Stop here and get a landscaper
- The ground slopes enough that the patio needs a retaining edge, a wall or steps
- There is no way to keep the finished surface at least 150 mm below the damp-proof course
- Drains, inspection chambers or gullies need raising, moving or connecting
- The paving is at the front of the house for parking cars
| WHAT YOU SEE | WHY, AND THE FIX |
|---|---|
| Puddles on the patio after rain | The fall is too slight or runs the wrong way. Lift and relay the affected flags with the correct fall; small dips can be rebedded. |
| Flags rocking | Laid on dabs, or the sub-base has settled. Lift the flag, clean off the old mortar, and rebed it on a full bed. |
| Joints cracking and falling out | The joint mortar was too wet, too weak or laid in frost. Rake out the loose mortar and repoint in dry, mild weather. |
| White powdery bloom on the flags | Efflorescence, salts coming out of the concrete. It is harmless and usually weathers away within months; brush it off dry. |
| Weeds in the joints | Open joints or jointing sand washed out. Weed, then refill with mortar, jointing sand or a jointing compound. |
| Damp patch inside on the wall next to the patio | The patio is too high against the damp-proof course or falls towards the house. Stop using it and get it lowered; this needs a professional. |
| Cement stains on the face of the flags | Mortar dropped during jointing. Remove with a stiff brush and a paving cleaner made for cement residue, testing on a spare flag first. |
| Colour bands across the patio | Flags laid from one pack at a time. It cannot be fixed without relaying; next time mix from three packs. |
WHAT YOU SAVE
What it costs to do it yourself
| 80 concrete paving flags, 400 × 400 mm | €479–€879 |
|---|---|
| Clause 804 sub-base stone, 3 jumbo bags | €227.85 |
| Sharp sand for bedding, 20 bags of 25 kg | €99–€100 |
| Cement, 6 bags of 25 kg | €60–€63 |
| Kiln-dried jointing sand, 2 bags of 25 kg | €31.98 |
| Spirit level | €46.45–€72.45 |
| Rubber mallet | €14.95–€22.45 |
| FFP3 masks | €21.99–€22.99 |
| Total, first time, before compactor and saw hire | €981–€1,420 |
| DIY total | €980–€1,420 |
Guide prices compiled by the Locufy team from published Irish and UK provider price lists and 2026/27 cost guides. Updated 2026.
The flags are the biggest cost and the sub-base the biggest weight; ask the merchant how many bulk bags of stone your volume needs, since loose stone compacts down. Hiring a plate compactor and a wet saw for a weekend is cheaper than buying either.
RATHER NOT?
Patio layers near you, with prices shown
The ones who cover your area, nearest first, with one score from every review. No account needed to look.
Or post the job free and let them come to you.
Keep heavy furniture and pots off for a few days, and do not pressure-wash it for the first months while the joints harden.
Soil, broken slabs and concrete rubble do not go in household bins. mywaste.ie directs rubble to a civic amenity site that lists it, and skip hire companies generally recycle bricks and similar construction waste.
Top up jointing sand after the first few weeks as it settles, and repoint any mortar joint that cracks before water gets under the flags.
Wash mortar off trowels, the mixer and the barrow before it sets; dried mortar ruins tools.
Laying a patio: questions people ask
A hard surface to the rear of a house for use with the house is exempted development under Class 6 of Schedule 2 of the Planning and Development Regulations 2001, provided ground levels change by no more than a metre. Check first if your house is a protected structure or your estate has a planning condition.
For most domestic paving, the manufacturer's guidance is a compacted crushed-stone sub-base of 150 mm to 300 mm, deeper on soft or clay ground.
At least 150 mm below it, with the fall running away from the house.
About 1 in 60 away from the house, so a 3 m wide patio falls about 50 mm across its width.
Block paving is laid on a compacted grit sand bed. Flags and natural stone need a full mortar bed on a compacted stone sub-base; sand alone lets them rock and settle.
The Locufy Irish price guide puts patio laying at €80–€220 per m², typically €130. The groundwork is most of that cost.
MORE GUIDES
More DIY guides
Sources — checked October 2026
- Roadstone — sub-base and laying course: depths, compaction and falls
- Roadstone — kiln-dried jointing sand: application and coverage
- Kilsaran — block paving installation guide
- Bradstone — laying a patio, step by step: depth below the DPC, fall, bedding and jointing mixes
- HSA — silica dust: a clean air site, employee information sheet
- HSA — manual handling of loads, guide to the General Application Regulations
- Planning and Development Regulations 2001, Schedule 2 — exempted development, Class 6
- mywaste.ie — rubble
- mywaste.ie — bricks
- Woodie's — price check: paving flags and jointing sand
- Woodie's — price check: sand, hardcore and cement
- Woodie's — price check: cement and sand
- Woodie's — price check: FFP3 masks and safety equipment
- TJ O'Mahony — price check: under-paving grit sand
- TJ O'Mahony — price check: cement
- TJ O'Mahony — price check: spirit levels
- TJ O'Mahony — price check: Clause 804 hardcore and rubber mallets
- TJ O'Mahony — price check: rubber mallets