Skip to content
CleaningHQSearch

Mildew

The flat, powdery surface growth that appears on damp fabric, grout and shower curtains — and the carpet trade's procedure for it names no bleach at all.

In detail

Mildew is the term used for the flat, powdery or downy growth that forms on damp surfaces — fabric, grout, leather, shower curtains, tent canvas — as distinct from the raised, patchy colonies usually called mould. The distinction is not a mycological one and the two words are used loosely, but the practical difference is real: mildew tends to sit on the surface and to have started recently, which is why it often responds to treatment that leaves an established mould growth untouched. Two findings matter. The first is that the carpet institute's mildew procedure opens with a detergent solution and moves to an ammonia solution, and names no bleach anywhere in the entry — which is worth knowing on a soft surface where bleach would remove the colour along with the growth. The second is the one every mould authority repeats: treatment addresses what is visible, and the growth returns on the same schedule unless the moisture that produced it is dealt with. On fabric, mildew that has been left long enough to weaken the fibre or to stain it permanently is past the point where cleaning helps, because the organism has digested part of the material.

What works

Why

Aftercare and prevention

Hacks and claims involving this

Sources for this page

Sources

  1. Spot Solver: spot and spill removal procedures

    The Carpet and Rug Institute (CRI) · Trade or professional body

    Relied on for: That the mildew procedure is a detergent solution followed by an ammonia solution and warm water, and that no bleach is named in the entry. (states this directly)

    Verification: a person has read the passage relied on.

    Read on Sprint 5-10: fifteen entries, stain by stain. Sprint 30: enumerated at 296 from the publisher's own sitemap, 134 more read plus 'Unknown'. Sprint 38: 56 more, chosen against stains the catalogue lacked. 192 of 296 read. Supports the claim as stated.

  2. Mold Cleanup in Your Home

    United States Environmental Protection Agency (EPA) · Government or regulator

    Relied on for: That the moisture problem must be corrected or growth returns, and that removing visible growth is not by itself a solution. (states this directly)

    Verification: a person has read the passage relied on.

    Read on The 'Mold Cleanup' section and the 'Tips and Techniques' list. Supports a narrower statement — our claim was reduced. CleaningHQ had been prepared to attribute a bleach position to the EPA in either direction, which the page does not support. The catalogue now states only what the agency states — detergent and water, dry completely, fix the moisture — and the widespread belief that mould requires bleach is handled as an assessed claim resting on the absence of any authority recommending it, not as an EPA prohibition.

Last reviewed by a person on .

Share this page