Sightline testing closes that gap, and it’s simple enough that it should never be the step that gets skipped under time pressure.

The simplest version of this test is sitting in the intended back row seat, at roughly seated eye height, while someone writes on a similarly sized board, or a taped-out outline of the proposed size, at the proposed mounting height. Wherever possible, involve a lecturer or teacher who will actually use the room, since someone who plans to write detailed content daily will often notice legibility issues a purely visual walkthrough misses. Having a second person, ideally someone not involved in specifying the room, independently confirm the result adds a useful check against the natural tendency to see what you expect to see.

Beyond whether text is visible at all, check whether normal handwriting size remains legible, since a board can technically be visible from the back row while still requiring uncomfortably large lettering to read clearly. Also check for glare at different times of day, since a sightline that works under overcast light may not hold up under direct sun, and test with the room at least partially occupied where practical, since an empty-room test misses the effect of seated students partially blocking sightlines from behind them.

If a sightline test reveals that the proposed size or position does not work, treat it as useful information rather than a setback. It is far cheaper to adjust the specification at this stage than after a board has been manufactured and installed, and understanding exactly why it failed usually points directly to the needed adjustment. Document a negative result as clearly as a successful one, since it prevents the same oversized assumption being repeated on a future, similar room.

Take photos from the back row, noting the exact seat, time of day, and proposed size and height, so the record is useful if a similar test needs repeating for a comparable room. If your institution has several lecture halls of different sizes and shapes, avoid assuming a test in one room applies to all of them. For larger institutional orders, it’s worth specifying in the supplier contract that a sightline check will be conducted before final sign-off, since the cost of the test itself is negligible compared with correcting a poorly sized board after installation.

Finalising a size before ordering? Chameleon’s large classroom whiteboards team can help plan a sightline check before your specification is locked in.