Why has my timber floor changed colour near the windows?

A colour difference near a window or under a moved rug does not automatically mean the floor was installed badly. Timber and its finish can change appearance with light exposure and age. I would first look at the pattern of the change and compare it with where sunlight, rugs and furniture have been.

Different timber species and finishes can respond differently, so I would not promise that every floor will fade in the same direction. An exposed area may look lighter, warmer or darker than a covered one. The contrast can become noticeable when a rug that has stayed in one place is moved.

My first practical step is to reduce prolonged strong direct sunlight with suitable window coverings or shading. Where practical, vary the position of rugs and furniture once the finish's care instructions allow them. These measures can help manage uneven exposure, but they do not guarantee that timber will never change colour.

Before recommending a repair, I would also check that the mark is actually light-related. Moisture, cleaning residue and a reaction beneath a mat can need different treatment. Look at whether the shape follows the window, rug edge or a particular object, and note whether the surface feels different as well as looking different.

Do not try to bleach a patch or aggressively sand one small area to match the rest. For a suitable timber floor, refinishing may be an option after assessment, but the remaining timber and desired appearance still matter. Send a room photo and a close-up in ordinary daylight, and we can discuss prevention and the realistic options for improving the colour difference.