The Short Answer

A blackout curtain fabric is made to stop light passing through it, so a closed curtain can darken a room for sleep at any time of day. A dim-out fabric only reduces the light: the room becomes noticeably darker, but daylight still shows through the cloth. For hotel guest rooms, blackout is the standard choice, while dim-out fabrics suit restaurants, lobbies, meeting rooms and other spaces that need softer light rather than darkness.

The fabric is only half of the answer. A blackout curtain that is too narrow, hung too low or mounted with a gap above the track will still let light around its edges. This guide covers both parts: choosing the fabric and specifying the curtain so it actually darkens the room.

What Blackout and Dim-Out Mean

The two terms describe how much light a fabric lets through, not its colour, weight or style.

Blackout fabrics

A blackout fabric is constructed to block light. Manufacturers achieve this in different ways, for example with a dense multi-layer weave or with a coating or backing applied to the fabric. The result is that, when you hold the fabric up to a bright window, you should not see light through it.

Blackout fabrics come in many surfaces: plain weaves, textured looks and soft velvet-like finishes. A blackout curtain does not have to look heavy or technical. If an interior design calls for a particular look, the usual route is to find a blackout fabric with that surface, or to combine a decorative face fabric with a blackout layer behind it.

Dim-out fabrics

A dim-out fabric is dense enough to reduce light and glare noticeably, but it is not designed to block light completely. Behind a closed dim-out curtain, a room is shaded and calm, yet you can still tell whether it is day or night. Terms vary between suppliers: you will also see "room darkening" or "light reducing" used for the same idea.

Because there is no single industry-wide percentage behind these words, always judge a dim-out fabric from a physical sample held against daylight, not from its name.

Blackout vs Dim-Out at a Glance

The table summarises the practical differences for hotel use. Fabric performance always depends on the specific fabric and colour, so confirm it with the manufacturer's sample.

Point	Blackout curtain	Dim-out curtain
Light through the fabric	Designed to block light	Reduces light; daylight still visible
Main purpose	Sleep at any time of day	Glare control and softer light
Typical hotel areas	Guest rooms, suites, staff rest rooms	Restaurants, lobbies, lounges, meeting rooms, corridors
Usual partner layer	White sheer on a double track	Often used alone, or with a sheer
Appearance	Full, heavier drape; many surface finishes	Often lighter drape; wider range of looks
Edge light leaks	Very noticeable in a dark room, so width and mounting are critical	Less noticeable, because the room is not fully dark
Colour choice	Colour does not change the blackout effect	Darker colours generally reduce more light than pale ones
How to verify	Hold a sample to a bright window	Hold a sample to a bright window and compare options

Why Guest Rooms Usually Need Blackout

Guests arrive on late flights, sleep in after events, rest between conference sessions or work night shifts. A guest room has to be dark whenever the guest wants it to be, which in practice means a blackout curtain.

In the hotel tenders we have worked on recently, the request was almost always the same: one blackout curtain and one white sheer curtain per window, on a double track. The sheer gives privacy and filtered daylight during the day; the blackout is drawn at night or whenever the guest wants a dark room. Our hotel curtains page describes this room package in detail, including the standard fabrics we use.

Dim-out curtains in guest rooms tend to generate complaints for one simple reason: guests expect a hotel room to be dark. If the design team wants a lighter-looking curtain, choose a blackout fabric with a lighter colour or a softer surface rather than dropping to dim-out.

Where Dim-Out Makes More Sense

Outside the guest rooms, the goal is usually comfortable light rather than darkness:

Restaurants and breakfast rooms: reduce glare on tables in the morning or evening sun without making the room feel closed.
Lobbies and lounges: soften strong daylight on large glazed areas while keeping the space bright.
Meeting and function rooms: dim the room for screens and presentations. Where a full blackout is needed for projection, specify blackout for these rooms as well.
Corridors and stairwells: reduce heat and glare where no one sleeps.

For large glazed walls in public areas, blinds are often a practical alternative or complement to curtains. Blackout and light-filtering roller blinds and motorised blinds can be combined with curtains in the same project.

Stopping Light Around the Curtain

A blackout fabric only darkens the room if the curtain closes off the window completely. Most "my blackout curtain lets light in" complaints come from the edges, not the fabric. These are the points to specify:

Width and side overlap

A curtain made to the glass size alone ends up too narrow. For hotel blackout and sheer curtains we add an allowance of 10 cm on each side of the window or wall width, so that the closed curtain covers the window edges. That is why we ask for the wall or facade length per window, not only the glass size, together with the number of panels per window.

Fullness

Fullness is how much fabric is used compared with the finished width. In the hotel tenders we have priced recently, the specification was 80% pleating, meaning a fabric width of 1.8 times the finished curtain width. Too little fullness makes a curtain look flat and can open gaps where panels meet.

Track position and drop

Light leaking over the top of the curtain is common when the track sits low on the wall with a gap to the ceiling. Ceiling-mounted tracks, or a pelmet or ceiling recess, reduce this. At the bottom, the curtain drop is calculated from the room height and the track position; because room heights often differ between room types in the same building, send the height per room type.

Overlap in the centre

Where two panels meet, they should overlap rather than just touch. Discuss this detail with your manufacturer when you choose the track system.

Double track layout

On a double track, the sheer runs on the window side and the blackout on the room side. Both layers are made to the same measurement logic, so they hang together correctly.

Fire Requirements Apply to Both

Whether a fabric is blackout or dim-out has nothing to do with its fire performance. Many hotel projects have fire-safety requirements for curtains, and the required documentation depends on the country, building type and authority. Documentation applies only to the exact fabric it was issued for, so state your requirement at tender stage. Our guide to hotel curtain fire-retardant regulations explains how to approach this, and our Quality Documents page lists the documents we can currently share.

How to Write It Into a Tender

To get comparable quotes, write the light requirement per area into the BOQ or room schedule:

Curtain type per window type: blackout, dim-out, sheer, or a combination.
Fabric reference or colour: or a description of the look you want, so suppliers can propose matching fabrics.
Fullness and heading: for example 80% pleating with a single pleat heading.
Wall or facade length per window: plus the number of panels per window.
Room height per room type: and whether tracks are ceiling- or wall-mounted.
Track type and operation: single or double, manual or motorised.
Fire requirement: the documentation your project needs.

Our article on how to prepare a hotel curtain tender walks through the full BOQ and room schedule.

How We Supply Hotel Curtains

LuxiVeil is the export brand of Gökcan Home, a curtain and blind manufacturer producing in Antalya, Türkiye, since 1994. For hotels we make guest-room packages of blackout and white sheer curtains, made to measure in our own workshop, on single or double tracks, manual or motorised. Our standard hotel blackout fabrics typically weigh around 300 g/m². Fabric samples are sent for approval before production, so your design team can check colour and light blocking under the room's own lighting. We have produced for hotels including Sirene Belek Hotel and Titanic Hotels. For curtain dealers and projects outside hospitality, see our wholesale curtains page.

Frequently Asked Questions

What is the difference between blackout and dim-out curtains?

A blackout fabric is made to stop light passing through it, so the closed curtain can darken a room completely. A dim-out fabric reduces light and glare but still lets some daylight through. The difference is in the fabric's construction, not its colour.

Are blackout curtains necessary in hotel rooms?

For guest rooms they are the usual standard, because guests need a dark room at any time of day. Most hotel tenders specify a blackout curtain together with a sheer curtain on a double track.

Why does light still come in around my blackout curtains?

Usually because of the edges rather than the fabric: the curtain is too narrow for the window, the track leaves a gap to the ceiling, or the panels do not overlap in the centre. Side allowance beyond the window, ceiling mounting and centre overlap solve most of these problems.

Does a dark colour make a curtain blackout?

No. A dark dim-out fabric is still dim-out. A blackout fabric blocks light because of how it is constructed, and it can be produced in light colours too.

Can a decorative fabric be made blackout?

A common approach is to combine the decorative face fabric with a blackout layer behind it, or to choose a blackout fabric with a similar surface. Send the fabric reference or a photo, and ask for samples before approval.

Do you supply blackout and sheer curtains for hotel projects?

Yes. We make blackout and sheer curtains to measure with single or double tracks, manual or motorised, and price each curtain type against your BOQ or room schedule. Send your documents through our RFQ form.

Request a Quote or Fabric Samples

If you are planning a hotel renovation or a new build, send us your BOQ or room schedule with window sizes, room heights, the curtain type per area, fullness and heading, fabric reference or colour, track type and operation, your fire requirement and the delivery address. We will return a quotation per curtain type with freight shown separately, followed by fabric samples for approval. Use the quote form on our contact page, or message us on WhatsApp for a quick first answer.

Blackout or Dim-Out Curtains: Which Should a Hotel Room Use?