The phone call comes about four hours after I have left. There is a gap at the skirting. You can see the gripper.
It has happened to me. It has happened to everyone who has run a wand for more than a couple of seasons, and any operator in London who tells you they have never shrunk a carpet is either very new or not being straight with you. What separates the trade is what happens next, because a shrunk carpet is usually recoverable and the recovery is a fitting job rather than a cleaning one.
Most of the time, though, the shrinkage was already waiting. The clean just cashed the cheque.
What is it that shrinks when a carpet shrinks?
Not the face fibre, in the great majority of cases. Nylon and polypropylene are dimensionally stable when wet and they are what most London carpet is made of. The movement comes from the backing.
A tufted carpet is a primary backing – usually woven polypropylene these days, jute on anything older – with tufts stitched through it and a secondary backing laminated on with SBR latex. Jute is the troublemaker. It is a bast fibre, it absorbs a great deal of water, it swells across its width when wet and contracts as it dries, and unlike the polypropylene it is glued to, it does not return to where it started.
Woven carpet is worse again, and Axminster and Wilton constructions carry jute in the weft. There is no secondary backing to restrain anything, so the shrinkage runs straight through the structure and shows up as a carpet measurably smaller than the room.
Wool adds a second mechanism. Wool felts – the scales on the fibre surface ratchet against each other under heat and agitation, and the pile draws in on itself. Felting shrinkage is not recoverable by stretching, and as often as not it turns up alongside jute shrinkage on the same carpet, which is why an old wool Axminster is the highest-risk thing in the domestic book.
The 2 per cent that matters
A jute-backed carpet can move 2 to 3 per cent across its width under heavy wetting. In a bedroom that is not much. Across a 6-metre through-lounge in a Victorian terrace it is 12 to 18 centimetres, which is a gap you can put your foot in.
The maths is why open-plan rooms and long hallways produce almost all the serious claims and small bedrooms produce almost none.
Was it the clean or was it the fitting?
I will state my position plainly and it is one that puts me at odds with a lot of loss adjusters: the substantial majority of post-clean shrinkage in London homes is a fitting failure that cleaning revealed, rather than damage that cleaning created.
Carpet is meant to be installed on gripper under tension, stretched with a power stretcher so the backing is held taut and the gripper pins have real load on them to bite against. A power stretcher is a large, awkward tool that takes twenty minutes to set up in a room. A knee kicker takes none.
Walk into a flat conversion in Walthamstow or a new letting in Sutton and the odds are heavy that the carpet went down with a knee kicker alone, by a fitter paid per room, working four flats that day. That carpet has almost no reserve tension in it. It looks fine dry, it looks fine for years, and the moment it takes on water and the backing pulls even slightly, the edge lets go of the gripper and travels.
The same carpet fitted properly moves the same 2 per cent and stays hooked on, because there was tension to give up.
What I say to a client at that point
Not that it is their fitter’s fault, on the doorstep, four hours in. That conversation lands as excuse-making, and rightly.
I say it can nearly always be put right, I say what it will take, and I get the re-stretch booked. The fitting conversation happens afterwards with the evidence in front of us, which is usually a gripper strip with clean, unworn pin tips where a properly loaded carpet would have worn dimples in the backing.
Can shrinkage be reversed?
Jute shrinkage, yes, most of the time. Felting shrinkage, no.
The method is re-stretching, and it needs a power stretcher and someone who knows how to sequence it. Room stretched from a fixed corner, tension worked across and then down, carpet re-hooked onto gripper, excess trimmed and tucked. Done properly it is invisible.
Timing matters more than people expect. A carpet that has just shrunk is easier to bring back than one that has sat shrunk for six months, because the latex has had time to set into the new geometry and the backing has, as often as not, taken a shape. Inside a fortnight is straightforward. After a year you are sometimes short of material and there is nothing to trim, which turns a re-stretch into a carpet you can no longer fit to the room.
Where the carpet has pulled so far that the width no longer reaches, the options thin out fast. A strip let in from a wardrobe base or a cupboard offcut, seamed and disguised under furniture. Or a smaller repair scope: stretch what you can, accept a beading trim at one edge, live with it.
Felting is different and there is no honest good news. The fibre has physically interlocked and it cannot be unlocked. What can be done is masking – careful pile grooming and sometimes a light steam and brush to lift the surface appearance – and it improves the look without recovering a single millimetre.
Underlay, which nobody checks
Half the re-stretches I attend have a second problem underneath. Crumb rubber underlay that has broken down, or PU foam that has taken water and compressed unevenly, gives the carpet a soft, inconsistent bed and the stretch will not hold.
Lift a corner and press it. If it feels like damp cake, the underlay is spent and re-stretching over it buys you eight months.
How do you avoid it in the first place?
Identify the construction before any water goes down. Fold a corner back at the doorway. Woven jute weft, a jute secondary, or a hessian-look backing on anything that feels like it predates the millennium – that is a carpet I treat differently for the rest of the job.
On those, I run a low-moisture system. Encapsulation or a properly wrung pad, minimal water, aggressive dry passes, air movers in from the start rather than at the end. On a high-risk woven wool I will decline hot water extraction outright, and I have lost jobs to firms who would do it, and one of those came back to me eleven weeks later as a re-stretch quote.
Where hot water extraction is the right call, the controls are solution temperature kept moderate on wool, dry strokes at a ratio of at least two to one, and vacuum pressure that is being maintained rather than assumed. A truckmount with a tired blower puts more water in and takes less out, and a lot of London vans are running on hours nobody has logged.
I also stop and check the edges halfway through a large room rather than at the end. Thirty seconds with a thumb along the skirting at the far side tells you whether the carpet is starting to move while there is still something you can do about it – drop the pass, get the movers on, finish dry. Found at the end of the job it is a phone call. Found halfway it is as often as not just an adjustment.
Something I would push back on, because it gets repeated as if it settles the question: low-moisture systems are sold as shrink-proof and they are not. They reduce the risk substantially. A carpet fitted with no tension on failing underlay in a 24-degree flat can still move under an encapsulation clean, and the operator who believes the machine is doing the safety work stops doing it themselves.
Stair runners and rugs
Runners are their own case because the tension is vertical and the fixings are discrete. A jute-backed runner that shrinks will pull off the nosings and expose the tacks, which is a trip hazard on the exact part of the house where you least want one.
Wash a loose rug off the floor, always. A jute-foundation flatweave dried in situ on a bathroom floor in Ruislip once came back to its owner three centimetres narrower and permanently corrugated, and there is nothing to stretch a rug back onto.
What should you ask for if it has already happened?
Ask whether the firm is going to re-stretch it themselves or subcontract to a fitter. Both answers are acceptable. Neither answer being available is not.
Ask for it inside two weeks. Chase it. The window closes.
Ask what happens if the stretch does not hold. Get that answer before the work rather than after – underlay replacement across a lounge is a real cost, and it is far easier to agree who carries it while everyone is still being reasonable with each other.
If the firm has gone quiet
Document it now. Photographs with a tape measure in frame at each affected edge, the date, and the invoice.
Then get an independent inspection from someone who does not clean carpets for a living, because their report is worth something and mine, on my own job, is worth nothing.
The last one I shrank was a wool-rich Wilton in an Enfield dining room, second week of a heatwave, and I knew before I finished the second pass. I rang a fitter I use from the doorstep and he came the following morning. It cost me ninety pounds and a Saturday I had planned to spend elsewhere, and the client has had me back twice since.