How to insert a DWG file as a block in AutoCAD

Inserting vs externally referencing — pick the right one

AutoCAD offers two ways to bring an external DWG into your drawing, and they behave very differently.

INSERT copies the file's contents in as a block. The geometry becomes part of your drawing, lives in its block table, and survives even if the original file is deleted. This is the right choice for blocks — chairs, doors, symbols — that you place and then own.

XREF (the ATTACH command) links the file rather than copying it. The external drawing stays separate on disk and your drawing just displays a reference to it; if it updates, your drawing reflects the change, and if it moves, the reference breaks. Xrefs are for large, evolving documents like a shared site plan or a structural grid, not for small reusable blocks. For downloaded library blocks, you almost always want INSERT.

Set your units first

Before inserting, make sure your drawing's insertion units are set, because that is what lets AutoCAD scale the incoming block correctly. Type UNITS and confirm the insertion scale matches your drawing — Millimeters for the millimetre blocks on this site in a mm template, or your own unit if you work in metres or inches.

With units set, the DWG comes in at true size automatically. Skip this step and a block can arrive 1000 times too big or small, which is the most common insertion complaint. Setting INSUNITS once in your template means you never think about it again — the file simply lands at the right size whatever unit you draw in.

Inserting with the INSERT command

The classic route is the INSERT command. Type INSERT (or just I) and press Enter to open the Blocks palette, then click the 'Libraries' or 'Recent' tab and use the '...' browse button to navigate to your downloaded DWG. Select it.

Before placing, decide your options. Tick 'Insertion Point: Specify on-screen' so you can click where it goes. Set the scale — leave it at 1 if your units are correct — and set a rotation angle, or tick 'Specify on-screen' to rotate as you place. Then click in the drawing to drop the insertion point, and if you chose on-screen rotation, move the mouse and click to set the angle. The DWG is now a single block reference in your drawing, ready to move, copy or array.

Inserting from the Blocks palette

Modern AutoCAD leans on the Blocks palette (the BLOCKSPALETTE command, or Insert > Block from the ribbon), which is friendlier for browsing.

Open it and you get tabs for Current Drawing, Recent, Favorites and Libraries. To insert a downloaded file, go to the Libraries tab, browse to the folder holding your DWG, and the palette shows a thumbnail. Set the scale, rotation and 'Repeat placement' options along the bottom, then either drag the thumbnail onto the canvas or click it and click to place. 'Repeat placement' is handy when you are dropping several of the same block — it keeps the insert command running so you can click, click, click down a row of seats without restarting each time.

Scale, rotation and mirroring as you place

You can transform the block at the moment of insertion rather than fixing it afterwards.

Scale: enter X, Y and Z scale factors in the dialog. Enter 1 for true size. A negative X scale mirrors the block horizontally — useful for flipping a door's hand or mirroring a kitchen layout without a separate MIRROR command. A negative Y scale flips it vertically.

Rotation: set an angle in the dialog, or tick 'Specify on-screen' and rotate live by moving the cursor. Snapping rotation to a known angle (with ORTHO or polar tracking) keeps a block square to a wall.

Uniform scaling is usually what you want for furniture and fixtures so proportions hold; non-uniform X/Y scaling is occasionally useful for stretchable elements but can distort a symbol, so reach for it deliberately.

After insertion — layers, exploding and editing

Once placed, the block is a tidy single object, which is usually exactly what you want. A few follow-ups are worth knowing.

Layers: the block typically inserts onto your current layer, while its internal geometry may sit on the layers it was drawn on. Set a sensible current layer (a furniture or fixtures layer) before inserting so the block reference lands where it belongs and you can freeze it as a group.

Exploding: if you need to edit the raw geometry of one copy, EXPLODE breaks the block reference back into lines and arcs — but you lose the single-object behaviour, so explode a copy, not your whole layout. To change every instance at once, use BEDIT instead and edit the definition. Keeping blocks unexploded is what preserves their main benefit: copy them freely, and one definition edit updates them all.