Window and door frames tend to gather dust and dirt over time especially depending on your environmental surroundings.
We recommend cleaning the frames every time you are cleaning the glass in order to keep the frames dirt and grime free.
uPVC frames can be cleaned using a mild detergent and water
Do not use thinners or spirits on foiled frames as this can cause them to discolour or peel
Do not use abrasive steel wool or scrapers as these can damage the frame
uPVC cleaners are available online or in most building supplies shops
Cleaning the frames every few months should be sufficient although if you live in a coastal or industrial area you may need to clean them more frequent.