In short: how to approve samples
A material sample is never approved on its own. It is approved next to the materials that will sit beside it, under light close to the room's final lighting, and recorded in writing: manufacturer, range, reference, colour, finish, format and, for tiles, the batch. The approved sample stays on site as the master until the end of the works, and every delivery is checked against it before installation.
It takes a few meetings and a little discipline. In return, you will not discover that the floor is "a bit cooler than it looked" once it is already glued down.
View materials together and in the right light
Put samples of everything that will sit together on one table: flooring, furniture timber, worktop stone, wall paint, the metal of handles and taps. Materials that work individually can combine unexpectedly: a warm oak next to a cold grey stone, a white paint that looks yellow beside a white tile.
Look at them in daylight from the direction it will come from, and under artificial light. A 2700 K lamp and a 4000 K lamp change the same shade beyond recognition. Look at flooring on the floor, not in your hand; wall finishes vertically. A photo helps you remember the decision, but it does not reproduce the shade and texture accurately.
Natural materials: a sample is not a promise
Stone and timber vary from slab to slab and board to board. A small marble sample shows the colour but not the veining. If that matters, visit the yard, pick the actual slabs and write down their numbers. For parquet, confirm the grade: a rustic grade has more knots and colour variation than a select grade. Ask for a larger sample or photos of an installed floor in the same grade.
In the Urgel flat in the Eixample the floor is herringbone parquet. For a floor like that, besides species and grade, you approve the block size, oil or lacquer and the tone of the finish, because the same oak under different oils looks like two different woods.
What exactly to record on approval
A note like "grey tile, as per sample" pins nothing down. Record the manufacturer, range and reference, the catalogue colour, the finish (matt, polished, brushed), the format and thickness and the edge type. For tiles, the shade and calibre of the batch, which are printed on the box. For installation, the pattern, joint width and grout colour, and the direction.
Add the date, who approved it and a photo of the sample with its label. If approval happens by message, one clear message with these details beats ten voice notes. An approved sample does not mean every future tile will match it exactly, but it sets a clear reference point.
Statuses and a single register
Give every item a status: proposed, sample awaited, approved, ordered, delivered and checked. There is one register: a table seen by you, the buyer and the installer. Two parallel lists in different chats all but guarantee the wrong reference gets ordered.
The rule is simple: nothing is bought on the strength of an ambiguous message. "Go on, I think the second one" is not an approval. If an item is not marked "approved", it is not ordered, even when the schedule is tight. A wrong tile order for an entire flat costs more than a week's wait.
When to approve: lead times decide
Some materials arrive quickly; others take weeks or months: made-to-order stone, parquet in a specific grade, imported sanitaryware, bespoke furniture. Those items are approved first, even before demolition, because their lead times drive the schedule for the whole renovation.
Each item needs a decision deadline tied to a stage of the works. The tiler cannot start the bathroom without tiles, and the joiner cannot start without an approved veneer. A late approval does not just delay one item: it stops a crew that is waiting for the material.
Checking deliveries and the master sample on site
When material arrives, it is compared with the master sample before installation. Several tile boxes from different parts of the pallet are opened, the batch is confirmed to be the same and the tiles are laid out dry on the floor. Parquet is checked from several packs. Stone is checked against the numbers of the chosen slabs.
If something does not match, work stops before installation: fixing it afterwards costs many times more. Substituting an equivalent material goes through a separate review and needs your agreement, which we cover in a dedicated article. The master sample stays on site until final handover: the result is checked against it, not from memory.