Quick answer
Measure from the finished mattress top and seated reading position, then move the sample until the page is lit without a bright source in either guest's eye line.
Bedside wall light height above mattress is best set from a finished bed and a seated reader, not copied from a generic floor dimension. The useful reference is the top of the installed mattress with the intended pillows in place. From there, test whether light reaches the book without a bright source appearing in either guest's eyes. A wall sconce used for atmosphere and a focused reading head may need different vertical positions. The room elevation should record both the chosen reference point and the exact fitting geometry before electrical boxes or headboards are fixed.
Measure the bed that will be installed
Confirm the mattress and topper thickness, bed base, headboard height and usual pillow stack. A small change in any one of these can move the reader's eye line and book plane. Mark the top of the finished mattress on the sample-room wall, then mark seated shoulder and eye positions for more than one likely posture. The proposed light should be tested with the selected shade or optic, not just a cardboard outline of its backplate.
Some online guides offer a height range, but those ranges assume a particular bed and source position. Treat them as rough starting points rather than an installation instruction. A fixed shade may be best judged by where its lower edge sits relative to the seated eye. An adjustable head must also be judged by pivot location, reach and parked position. The headboard placement guide covers those additional axes.
Test the page and both eye lines
Place a book where the guest naturally holds it while upright, then again while reclining. Move the sample until useful light stays on the page without the head casting a shadow. From the adjacent pillow, look toward the fitting and check for a visible LED or reflected hotspot. A position that is excellent for one sleeper can be intrusive to the other.
Do the test with the room's ambient lights both on and off. At low ambient level, glare can feel more prominent. Check the switch from the same seated position; a perfectly aimed fitting that is hard to turn off is a poor bedside solution. Record the approved position in a photograph and dimension it on the elevation from the stated mattress datum, not from an undefined “bed height.”
Adapt the height to the mounting format
An adjustable head such as MD-WL-Y092 has a documented flexible 3 W reading light. Its flexibility can help accommodate posture changes, but the installed mount and arm must still clear pillows, artwork and cleaning access. A surface-mounted lamp with a shade may have a different visual center. Do not transfer a successful pivot height from one format to another without retesting.
If the light is mounted in a headboard, the joiner must check the panel thickness, fixing support and cable route before a height is frozen. If it is fixed to the wall behind the headboard, allow for panel projection and a service path. The electrical designer should confirm the wiring and destination-market requirements; an editorial guide cannot authorize field connections.
Release a repeatable detail
Put the final mattress datum, light centerline, horizontal offset, switch position and fixture revision on one coordinated drawing. Include the approved sample photograph and note whether the dimension refers to a mounting center, pivot, shade edge or light-emitting aperture. Those points are not equivalent. Recheck the first installed room against the mock-up before repeating the detail down a corridor. If the bed specification changes, reopen the height decision rather than relying on the old drawing.
