Cleaning blinds without ruining them

The blinds we get called out to replace before their time are rarely worn out. They have usually been cleaned — soaked, scrubbed, pressure-washed or polished — by someone doing their best with the wrong method. Blind fabrics are engineered surfaces, and most of what damages them is water where water should not be.

The routine that prevents most work

Dust weekly or monthly with a vacuum on its lowest suction and a brush attachment, working top to bottom. Dust is not cosmetic: on a screen fabric it settles into the weave, holds moisture, and in a humid room becomes the food source that mould grows on. In a kitchen make it fortnightly, because airborne grease binds dust into a film that no dry method will lift once it has set.

Fabric rollers and zebras

For a screen or sunscreen fabric: a cloth damp with water and a drop of mild dish soap, wiped along the weave, then dried with a second cloth. Work with the blind lowered and support the fabric with your hand behind it so you are not pushing against the tube. For a blackout fabric, dust and vacuum only. The acrylic foam backing that makes it blackout will delaminate if it is soaked, and the failure shows up weeks later as bubbles and a stiff, papery panel — this is not a warranty defect and it cannot be repaired. Never put any blind fabric in a washing machine, and never take a scrubbing brush to a zebra: the sheer bands are the weakest part and they ladder.

Spot marks: blot, do not rub, and start from the outside of the mark inwards so you do not spread a ring. Fingerprints and food marks generally come off with the damp-cloth method. Ballpoint, crayon and adhesive generally do not, and solvent will strip the coating faster than it lifts the mark.

Mould spots in a humid room

Common in bathrooms, in coastal houses and in condominium units closed up for weeks with the aircon off. Treat it with a 1:4 solution of white vinegar in water on a cloth, dab the affected area, leave a few minutes, wipe with clean water and then dry the fabric completely with the blind fully lowered and the window open. Do not use bleach on fabric: it takes the colour and weakens the yarn, and on a coated fabric it dulls the coating permanently.

Then deal with the cause, because mould is a humidity problem wearing a blind as a costume. Ventilate, run an extractor, and if the room is persistently damp, change the product rather than the cleaning routine — PVC roller or faux wood in a bathroom, never a Roman blind or real timber.

Aluminium venetians

Close the slats flat, wipe across the whole face with a microfibre cloth, then reverse the tilt and repeat. Two passes and you are done. Support the slats with your other hand as you wipe so you are not putting a bend into a 0.21 mm slat, and never grip and pull a slat to hold it steady. For a kitchen venetian with a set-on grease film, warm water with a little dish soap on the cloth, then a dry pass. Skip the specialist slat-cleaning tongs sold online: they force both faces at once and are the most common cause of the wavy slat people then blame on the blind.

Real wood and faux wood

Dry dusting only on real basswood, or at most a barely damp cloth followed immediately by a dry one. Do not use furniture polish or silicone spray: it builds a film that traps dust and it can soften the lacquer. Water left standing on an end grain is what starts a warp, so if you spill on a wood blind, dry it now rather than later. Faux wood PVC is much more forgiving and takes a damp cloth with mild soap happily, which is precisely why we put it in wet areas.

Verticals and exterior blinds

Vertical louvres unclip from their carriers, which makes them the easiest of all to clean properly: lay them flat, wipe both faces, and rehang. Take out the bottom chain first and note the order. For exterior blinds — acrylic canvas and PVC mesh — hose down and brush gently with mild soap twice a year, quarterly if you are within a kilometre of the sea, and let them dry fully extended before retracting. Never pressure-wash an exterior blind: the jet drives water into the weave, strips the coating, and can force the fabric out of its channel guides.

The four things that void a fabric warranty

• Immersing or machine-washing any fabric, especially a blackout coating.
• Bleach or solvent on fabric, and any abrasive cleaner on a coated surface.
• Pressure-washing an exterior blind, or leaving one down above 60 km/h of wind.
• Forcing a mechanism that has jammed instead of calling for service — a jammed chain is a ten-minute fix, a snapped tube is a new blind.

Once a year, look at the hardware rather than the fabric: check bracket screws are tight, that a chain tensioner is still fixed to the jamb, and that a breakaway connector has not been reconnected wrongly after a snag. Blinds fail at their fixings far more often than at their fabric.