Test one sample in the position that will be seen
Colour and sheen change with daylight, artificial light and surrounding surfaces. Apply a small authorised sample to a prepared test board or inconspicuous agreed area, following product instructions. View it at useful times of day and beside the retained finish. Hardware should also be sampled where possible: check projection, grip, screw spacing and movement before buying a full set. A nominal size or online image is not proof of fit. If the proposed item affects a visible exterior or controlled estate detail, establish permission before sampling on the building. Record the approved sample with its product code and date. This modest trial reduces wasted materials and prevents a widespread mismatch being discovered only after several rooms are changed.

