Wet carpet is a two layer problem and almost every failed attempt treats it as one. The carpet is the part you can see and the pad underneath is the part that holds the water, and a pad that stays wet will keep the subfloor wet and grow mould under a carpet that feels dry to the hand. Whether the carpet can be saved depends far more on what the water was and how long it sat than on how much of it there is.
Carpet water extraction in the first few hours, on clean water
With clean water and a fast response, carpet is frequently saved. Extraction comes first and it is not a domestic wet vacuum passed over once: it is repeated slow passes with a proper extractor, which pulls water from the pile and from the pad beneath. Then the carpet is floated, meaning lifted at an edge and air blown underneath, or the pad is removed and the carpet dried separately. Air movers across the surface with a dehumidifier running is the combination that works; a fan alone moves humid air around the room.
Mold in carpet: when the pad goes and when the carpet goes
The pad is discarded far more often than the carpet, because it is a sponge that is cheap to replace and slow to dry. If the water was grey or black, both go without argument, since neither can be decontaminated reliably. If the water sat for more than a day or two, both usually go. If the carpet is delaminating, has lost its backing bond, or has been stained by dyes from furniture legs or from the subfloor, it goes. Wool and natural fibre carpets shrink and are less forgiving than synthetics.
Wet carpet mold, and how fast it starts
Growth on wet materials typically begins within 24 to 48 hours, and carpet backing, pad and the dust in both are ideal substrates. Mold in carpet and mold under carpet are therefore a timing problem more than a hygiene one. The signs are a musty smell strongest at floor level, a carpet that stays cool and damp at the base of the pile, dark patches appearing on the underside, and a subfloor stain following the wet line. Once growth is established in the pad, cleaning the carpet does not solve it.
Carpet cleaning water damage, which is a different service
Ordinary carpet cleaning applies water and extracts it under controlled conditions; water damage restoration removes water somebody else introduced and dries the assembly under it. They use some of the same machines and they are not the same job, and a cleaning company without dehumidification and meters cannot dry a structure. Where the water reached the subfloor or the wall base, the work is restoration and the record it produces, readings and a drying log, is also what the claim is argued from.
Questions people ask about how to get water out of carpet
How do I get water out of carpet?
Extract repeatedly with a proper extractor rather than a single pass, then either remove the pad or float the carpet and blow air underneath, with a dehumidifier running. A fan alone does not dry an assembly.
Carpet flooded: can it be saved?
With clean water and a fast response, often yes. With grey or black water, or after a day or two, the carpet and the pad both go because neither can be reliably decontaminated or dried in time.
How quickly does mold under carpet start to grow?
Growth on wet materials typically begins within 24 to 48 hours. Pad and carpet backing are ideal substrates, which is why the pad is usually discarded rather than dried.
Is this the same as carpet cleaning?
No. Cleaning applies and extracts water under control; restoration removes unwanted water and dries the structure beneath with dehumidification and measured readings. Only the second produces a drying log.
Can water damage carpets be cleaned rather than replaced?
On clean water and inside the first day, often. On anything contaminated, or after the pad has been wet for longer, the carpet and pad are removed, because cleaning does not return grossly contaminated porous material to a sanitary condition.