Why uPVC discolours
uPVC frames and doors pick up traffic grime, dust and pollen, and in shaded or damp spots, green algae. Conservatory roofs are the worst affected because they're shallow, collect leaves and get little rain-wash. Left long enough, dirt can make white uPVC look yellow or grey.
What to use – and what to avoid
Warm water with a little washing-up liquid and a soft cloth or sponge is enough for most frames. For stubborn marks, there are cleaners made specifically for uPVC.
- Avoid abrasive pads, scouring powders and cream cleaners – they can dull the surface permanently
- Avoid solvents such as nail varnish remover and white spirit, which can damage the plastic
- Avoid harsh bleach on seals and gaskets
- Test any new product on a hidden area first
Cleaning frames and doors
Brush or vacuum loose dirt and cobwebs first, especially from the drainage channels and the tracks of sliding doors. Then wipe the frames with soapy water, rinse with clean water and dry with a cloth. Check the small drainage holes at the bottom of the outer frame are clear – if they block, water can build up in the frame.
Wipe rubber seals gently. A silicone-based lubricant recommended by your window supplier can keep seals and hinges working smoothly.
Conservatory roofs: safety first
Never climb onto a conservatory roof. Polycarbonate and glass roof panels aren't designed to take a person's weight, and falls from them cause serious injuries. Clean what you can safely reach from a stable stepladder with an extendable soft brush, or leave it to a professional.
Professional window cleaners often use water-fed poles with soft brushes and purified water, which clean roofs and high glass from the ground and dry without spotting.
Get quotes from local cleaners
Dealing with green algae
Light algae on frames usually comes off with soapy water and a soft brush. For heavier growth, use a product designed for outdoor uPVC and follow the instructions, rinsing well. Be careful near plants and ponds. Shaded north-facing frames will turn green again over time, so a gentle clean every few months stops it getting established.
Cleaning conservatory glass from inside
Inside, conservatories collect dust, cobwebs and condensation marks, especially on the roof panels. A long-handled microfibre mop or a soft flat mop on an extendable pole makes the roof reachable without climbing. Work gently – some roof panels have special coatings that scratch easily.
Wipe frames and sills, and clear the corners where insects gather. Condensation in the morning can be wiped with a cloth or window vacuum, which helps stop mould on seals and frames.
Hinges, locks and tracks
Grit in window and door tracks makes them stiff and wears the rollers. Vacuum the tracks, then wipe with a damp cloth. Sliding patio door tracks especially benefit from regular cleaning.
Window hinges and locks on uPVC frames should be kept clean and occasionally lubricated with a product recommended by the manufacturer. Avoid general household oils, which can attract dirt and damage seals.
How often to clean
Wiping frames when you clean the windows, and giving them a thorough wash twice a year – spring and autumn – keeps most uPVC looking good. Conservatory roofs benefit from a clean at least once a year, often after autumn leaf fall.
If you have a regular window cleaner, ask whether frames and sills are included or available as an add-on. Conservatory roofs are usually priced separately.
