French drain cost UK: read the range before you dig

The lawn is still soft a day after rain, and a line of silt sits along the patio. You look up the French drain cost UK and three 2026 guides hand you three different bills. One talks about £45 to £90 a metre installed. Another puts French drains at £150 to £250 a metre. A third puts many garden drainage jobs at £800 to £6,000, and then, in another answer, a French drain at £40 to £90 a metre. The fleece in the basket is priced in tens of pounds. Excavation, clean stone, pipe, spoil, and the person who digs are the rest of the bill.

Metre rates come from Costwise's French drain page (a September 2026 update note), Checkatrade's garden drainage guide dated May 2026, and BookaBuilderUK's 2026 garden drainage page. Fleece prices are shelf figures from amazon.co.uk listings. Peter F. is the editor for this note, updated in October 2026. We did not dig a trench or run a lab test. A qualifying purchase through our links can earn a commission at no extra cost to you. Blending the guides into one UK average would invent a figure none of them published.

In short

A French drain cost UK search returns bands that disagree: about £40 to £90 a metre in two guides, and £150 to £250 with a £200 average in Checkatrade's May 2026 guide. Materials, if you dig, sit nearer £10 to £20 a metre on Costwise's page. The fleece itself is a garden cut of about £26 to £44 in the amazon.co.uk set. Ask for an itemised quote, and keep any soakaway on its own line.

What the published ranges actually say

Read each page for what it counted. A midpoint blended from all three will not match the invoice. Costwise puts an installed French drain at £45 to £90 per metre, with about £60 as a typical figure, and materials at about £10 to £20 per metre if you dig.

Checkatrade's May 2026 guide prices French drains at £150 to £250 per metre, average £200, and a crate soakaway at £1,500 to £2,500. A lawn trench and a crate pit are different holes. If the quote is only the trench, the crate is another line.

BookaBuilderUK's 2026 page puts many jobs at £800 to £6,000, and in one answer a French drain at £40 to £90 per metre. Ten metres at £40 is £400, under the £800 floor of the whole-job band. The gap is the call-out, the spoil, the reinstatement, or a soakaway the metre rate left out. None of these pages is a tender for your garden.

Where the money goes

The installed bands move because the trench is labour and muck. The fleece does not explain a gap of about £100 a metre between two current guides. In the install notes we used, a French drain is a sloped trench lined with permeable non-woven geotextile, filled with clean stone around a perforated pipe, then closed so soil stays out of the stone. Draintex's sheet asks for about 75 mm of clean stone around the pipe and about 10 mm non-limestone gravel.

Growtivation's sequence uses about a 1% fall, 10 mm of drop per metre. A flat bed lets water sit in the stone. None of the three guides prints a short-run percentage, yet the contractor still attends, shifts clay, and makes the turf good. Ask whether the figure is a hand dig or a micro-digger, and whether the arisings stay on site. A new crate, on Checkatrade's figures, is £1,500 to £2,500 beside the trench.

What drainage fleece costs inside that bill

On the amazon.co.uk cuts on our drainage fleece comparison, garden pieces run from £26.02 for 6.75 m² to £44.06 for 22.5 m², roughly £2 to £4 per square metre. BuildWiz cites bulk 100 gsm nearer £0.78 to £1.56 per square metre. That bulk figure is not an amazon.co.uk price. The narrow piece is the Spudulica 1.1 m by 8 m trench fleece, B06ZYB3XDK, 8.8 m² of stated 100 gsm at £29.55, the top pick here for a short, narrow trench. A review cites a 300 mm clay trench. The average is 4.9 stars from 45 reviews, a small sample and not a lab test. The technical row says plastic while the bullets say non-woven geotextile, so read the live listing.

The 1.1 m by 10 m cut, B07CKQ1C1D, is £30.91, with 4.6 stars from 319 reviews, and one UK review measured it short of 10 m. Stated 100 gsm is not evidence of BS EN 13252 or BS 8661. That limit is on the buying guide. The Caisse cut, B06ZZR2QKZ, is 18 m² at £37.55 when 1.1 m will not close the trench. Skip the Lucky Reptile HF-100 at £8.99, a terrarium sheet. The 2.25 m by 10 m cut, B074S46496, is £44.06 and does not state gsm; a review reports a Lotrak 80 stamp. Fleece and weed membrane are different sheets. Laying order is on how to lay drainage fleece.

What a 15 metre run does to the arithmetic

Fifteen metres will not finish on one 8 m cut, and multiplying a headline by 15 is not a quote. Costwise's installed band is £675 at £45 and £1,350 at £90. About £60 becomes £900, and materials if you dig are £150 to £300. Two 8 m fleece cuts at £29.55 are £59.10. Draintex asks for 300 mm of overlap, and one such lap on two 8 m pieces leaves about 15.7 m of run if both lengths are true. Checkatrade's band is £2,250 to £3,750, £3,000 at the £200 average. A crate at £1,500 to £2,500 is extra. BookaBuilderUK at £40 to £90 is £600 to £1,350, while many of its whole jobs sit at £800 to £6,000.

The sheet around one small crate can be the 2.25 m by 3 m cut, B074PYK7M1, 6.75 m² at £26.02. A UK review used that area on two stacked Polystorm crates, tight once overlap is added. More fabric is set out on the soakaway crate wrap.

What to ask a contractor to include

Ask for length, width, depth at both ends, and fall. Growtivation's sequence is about 1%, 10 mm per metre, with the perforations laid downward into the stone. Name the pipe and the stone size. A Draintex-style note wants clean non-limestone aggregate of about 10 mm, with about 75 mm around the pipe. Name a non-woven geotextile and the overlap: 300 mm minimum on the Draintex trench sheet, or the figure in the guide you are following. If the quote only says membrane, ask which product. Give spoil, reinstatement, and VAT their own lines. A single figure cannot sit beside £60 or £200 until that split is visible.

When digging it yourself changes the bill

Doing the dig yourself is Costwise's step from £45 to £90 installed down to about £10 to £20 of materials. On 15 metres that is £675 to £1,350 against £150 to £300. Fleece at £29.55, or £59.10 for two cuts, does not include pipe or clean stone. The domestic case is a short, shallow lawn trench, services located, about 10 mm of fall per metre, and an outfall you may use. Cover the fabric the same day, and measure folded pieces before you bury them.

Stop when the job leaves that trench. A digger, unknown services, or a soakaway taking water from a building is a contractor's site. English notes talk about soakaways at least 5 m from buildings. That figure is English. It is not a fee, and we cannot state it as the rule in Scotland, Wales, or Northern Ireland. Moving a crate to meet a clearance lengthens the pipe. Ask the building-control body for your address before you compare metre rates.