Curtain linings, compared.

Unlined.

A single layer of face fabric with a hem. Light passes through it, heat passes through it, and the sun will fade it faster than a lined curtain because there is nothing behind it taking the UV.

There is one job unlined does well: a sheer or voile layer that softens glare and gives daytime privacy while keeping the outlook. As a warmth or darkness solution it does effectively nothing, so we would not specify it alone in a bedroom or a room you heat.

Standard lining.

A plain cotton-polyester lining sewn behind the face fabric. It adds a second layer and a small trapped air gap, which gives a modest thermal contribution, and it protects the face fabric from sun damage, which materially extends its life on a north or west-facing window.

It also improves how the curtain hangs, adding just enough weight to give a proper fold instead of a limp one, and it makes the window look consistent from the street because every curtain in the house shows the same neutral back. Standard lining is the baseline we assume unless there is a reason to go further.

Blockout lining.

A dense lining that passes effectively no light. This is the route to a dark bedroom when you want a particular face fabric that is not available as a triple weave. Two fabrics and more making labour puts a lined blockout curtain at $350 to $900 per window against $300 to $750 for triple weave.

Worth understanding: the blockout lining stops the light that hits it and nothing else. If the top, sides or bottom of the curtain are open, the room will not be dark no matter how good the lining is. That is covered properly in bedroom blockout curtains.

Thermal and coated lining.

A lining with a denser construction, or an acrylic foam coating applied to the back, designed to resist heat transfer better than standard lining. It adds $60 to $180 per window over a standard lining, which makes it the best value upgrade on most quotes if warmth is the goal.

A coated lining is a little stiffer than a standard one, so the curtain hangs with a flatter, more architectural line rather than a soft one. Some people prefer that look, others do not. Coated linings should be handled gently in cleaning, since the coating is the working part.

As with everything thermal, the lining only earns its keep if the curtain is sealed at the top, returned at the sides and long enough at the bottom. The mechanism is in the winter thermal guide.

Interlining, or bump.

A soft flannel-like layer sewn between the face fabric and the lining, so the curtain becomes three layers. This is the premium option and it does three things no other lining does. It adds genuine insulating bulk. It deadens sound, which matters near the Princes Highway or a main road. And it gives the deep, heavy, evenly spaced folds that people recognise as expensive curtains without knowing why.

Cost is $600 to $1,400 per window all up. The practical consequences are weight and space. An interlined curtain is considerably heavier, so the track, the brackets and the fixing surface all have to be specified to suit, and it takes more stack space when open, which has to be planned into the track length. It is the lining we specify most often in Berwick formal rooms and on the coldest windows in Emerald.

The condensation trade off, honestly.

This is the part nobody mentions until it becomes a problem. When you fit an effective thermal or coated lining and seal the curtain properly, you keep more heat in the room. The direct consequence is that the glass behind the curtain runs colder overnight than it did before, because less of your heat is leaking through it. Colder glass condenses more moisture out of whatever damp air is sitting in the pocket between fabric and window.

In tighter new double-brick estate homes around Officer and the Pakenham estates this is a real effect, and over a season it is where mould on the reveal starts. It is manageable and it is not a reason to skip lining. The practical rules are: open the curtains during the day so the reveal and the glass dry out, keep some ventilation in the wet rooms, avoid drying washing indoors against a closed window, and put the heaviest coated linings only in the rooms you actively heat rather than on every window in the house.

Relining curtains you already own.

If you like the face fabric and it is in good condition, adding or replacing the lining runs $150 to $400 per pair, which is usually the cheapest meaningful upgrade available. We check the heading, the hem allowance and whether the existing track will carry the extra weight, because a relined curtain is heavier than the one you started with. Pairing that with a pelmet, at $180 to $600, often transforms an existing curtain for a fraction of what a new one costs. See pelmets explained and the full 2026 cost guide.

Frequently asked questions.