A material in Stockroom is something you buy and build with but never sell, tracked in the unit you count it in. It can live as a draft product in your Shopify store, or in Stockroom only - with no Shopify product at all. That keeps one inventory - the one Shopify shows - while letting recipes say "12.5 g of wax" and purchase orders say "3 pails of 5,000 g".
Create or mark a material
In Inventory > Products, switch the segment to Materials and click New material: name, Stock unit, a cost per unit, and an opening quantity. Stockroom creates a draft product in your store (draft, so it is never sold), tracked at your location in that unit. Materials still show on the Products page under its default Active status - Active means everything live, materials included, so you never need to switch the filter to Draft to find them - and the bill of materials and build component pickers always list them. An existing product can become a material with Mark as material on its product page - pick the unit and it keeps its history.
Tick Keep this material in Stockroom only and no Shopify product is created: the material, its stock, its costs and the builds that consume it live entirely in Stockroom. That suits raw materials your store has no reason to list - resin, packaging, fabric by the metre. Everything else works the same: order it on purchase orders, receive it, count it, build with it. It just never appears in your Shopify admin.
Pick the unit small - grams rather than kilos, millilitres rather than litres - because stock counts are whole numbers in Shopify. Recipes take decimals in that unit (0.25 m), and Stockroom rounds across build records so nothing drifts.
Write a recipe in a different unit
A recipe line does not have to use the material's stock unit. If you count resin in grams, a line can still say 0.5 kg: pick kg in the Unit box beside the quantity and Stockroom stores the 500 g that actually comes off the shelf. The box only offers units it can convert exactly - grams, kilos, ounces and pounds for something counted in grams - so a quantity is never rounded behind your back. Pieces and sheets convert to nothing else. A build's component list has the same Unit box.
Weight and volume cross only when Stockroom knows how heavy the material is. Set Density on the material - grams per millilitre, so water is 1 - and something counted in grams can be written in millilitres. Without a density, that line is refused rather than guessed.
Buy in packs
Set a pack size on the material's stock settings ("Pail = 5,000 g") and purchase orders work in packs while stock stays in the unit: the PO line says 3 pails of 5,000, receiving adds 15,000 g, and restock rounds to whole packs. The product page and PO line show the unit everywhere a quantity appears.
Where materials show
Everywhere a product shows, with its unit beside every quantity - inventory, the product page, bills of materials, builds, Restock, reports and CSV exports.
In the component picker of a bill of materials, like any other product.
On stocktakes, adjustments, transfers, reorder points and alerts - nothing is special-cased.
Rename, delete or archive a material
Edit material on the material's product page changes its Name and Supplier. A material that is a Shopify product is renamed in Shopify too, straight away. Two materials cannot share a name.
A material kept in Stockroom only carries a Stockroom only badge and has Delete material on its page. You can delete it only while nothing uses it: no stock on hand, and not on any bill of materials, build, purchase order, adjustment, stocktake or other document. Deleting cannot be undone. When something does use it, the dialog says what, and offers Archive material instead. An archived material keeps its history and leaves your active lists, and Unarchive material on its page brings it back.
A material that is a Shopify product has no delete button in Stockroom. Archive or delete it in Shopify, like any other product.
To list only one kind, use the Material origin filter on the Materials segment: All materials, Shopify materials or Stockroom only. It shows once you have at least one Stockroom-only material.
Good to know
The unit is stored by Stockroom, not Shopify - Shopify shows the plain count. Change it with Change unit on the product page, but only until the material has been used: once you have counted it, put it in a recipe or drawn it into a build, the stock unit is locked, because every number already recorded means that unit.
Density stays editable either way. Changing it does not rewrite recipe lines you already saved - open a line and save it again if you want it restated.
A material that never sells has no sales history, so Restock looks at what builds consume rather than what sold; consumption-based reorder suggestions for materials are on the roadmap.
Un-marking a material (Not a material) keeps the product and its stock; it just stops showing the unit. It is not offered on a Stockroom-only material, which has no product to go back to - delete or archive it instead.