Flame Retardant
Made To Measure
Heavy Weight
British Made
Acoustic
5 Year Guarantee
Thermal
Mimas Soundproof Curtain | ✅ Lab Certified | Room Divider | Window, | Thermal | FR
Flame Retardant
Made To Measure
Heavy Weight
British Made
Acoustic
5 Year Guarantee
Thermal
Currently 3-4 Weeks - UK Manufactured
UK Mainland Over £250
FREE
Mimas Acoustic Curtains
Sound absorbing and sound reducing curtains, lab tested by two UKAS-accredited laboratories to BS EN ISO 354 and BS EN ISO 10140-2 / 717-1. Room dividers, windows, studios and stages.
Room divider
10 dB
certified, Lined Acoustic Blackout
Over a window
+2 dB
certified, 29→31dB
Absorption
0.80αw
Class B, EN ISO 354
Thermal
30%
less heat loss
Acoustic figures above are independently lab tested by UKAS-accredited laboratories. Thermal performance is a manufacturer specification, not a UKAS lab result.
Will it work for my situation?
Pick the closest match. This keeps expectations realistic.
Room divider / partition
One of the strongest use cases — 10dB certified, with no window or wall doing extra work alongside it.
Studio, stage or hall echo
Class B absorption reduces reverberation and improves clarity — used in recording studios and village hall stages.
Traffic and voice noise through a window
Genuinely helps, especially 800Hz–4000Hz. Result depends heavily on your glazing and how well the window is sealed.
Deep bass, engines, low-frequency rumble
Below around 200Hz the curtain makes little to no measurable difference — no lightweight curtain stops bass-frequency noise, and we don't claim otherwise.
Straight talk: over a window, your glazing is doing most of the work already. The curtain is a proven, certified upgrade on top of it — not a replacement for poor glazing or draughty frames.
What you get
Absorption and insulation
0.80αw Class B absorption. 10dB certified as a room divider, +2dB over a double-glazed window.
True blackout
3-pass coated acoustic lining blocks light entering or leaving the room.
Thermal regulation
Reduces heat loss by 30% over a double-glazed window when lined.
Hotel-quality fabric
28 colourways. A standard 200cm×200cm lined pair weighs around 8kg.
Fire retardant
Face fabric to BS5867 Part 2C, lining to Part 2B. The assembled curtain is rated to the lower of the two standards.
Choosing a construction
Three real constructions, not three marketing names for the same thing — see "Which option is right for me" below before you order.
Fitting makes the difference
This is exactly how our certified window test was rigged — not a generic recommendation.
Ideal vs practical: floor-to-ceiling and wall-to-wall gives the best possible result, but that's not achievable in most rooms — around 90% of the rooms we fit can't do it. Based on our own lab testing, the standard we recommend and test to is 30cm above the window or opening, down to the floor, and 30cm past each side.
1) 30cm above
Mount the track 30cm above the window or opening, down to the floor. This is the exact rig used in our UKAS window test.
2) 30cm past each side
Extend the track 30cm beyond the window or opening on each side to reduce sound leaking around the edges.
3) Seal drafts first
Air gaps are sound gaps. Improving seals around the frame or opening improves results before the curtain even goes up.
How the certified figures were measured
In our UKAS-accredited window test, the track was mounted 30cm above the window, extended to the floor, and 30cm past each side — the same standard we recommend for every installation. Fitting tight to the frame will produce a lower real-world result than the certified figure.
Why we publish the full breakdown, not just one number
A single weighted figure hides where the improvement actually happens. Honest framing sells better than a rounded-up headline number — see the frequency-by-frequency table below for exactly what to expect at each band.
You will also need a suitable track
Acoustic curtains are heavy — a standard lined 200cm×200cm pair weighs around 8kg. Standard plastic tracks and lightweight poles are not suitable.
Heavy duty metal curtain track
We recommend a metal heavy-duty track — our optimal track or roller runner track are both suitable for the full Mimas range.
View Roller Runner Track →Proof and testing
We publish our certificates. Many suppliers in this category don't test at all.
Window test: 29 dB baseline → 31 dB with curtain (+2 dB certified)
What the window test means
- Double glazing alone measures 29 dB
- Our Lined Acoustic Blackout curtain takes it to 31 dB (+2 dB, certified)
- Room divider result is 10 dB — curtain tested in isolation, no window involved
- Fitting height, width and draught-sealing all affect the real-world result
Absorption result
BS EN ISO 354:2003 · Unlined vs Lined Acoustic Blackout
Window insulation result
BS EN ISO 10140-2:2010 · Lined Acoustic Blackout
Room divider result
Rw by construction · 3-Layer figure is an estimate
What you actually hear, frequency by frequency
The dB scale is logarithmic and the single certified figure hides where the real improvement happens.
Where the +2dB weighted figure comes from
The certified Rw figure is a single standardised average across all tested frequencies, including deep bass below 200Hz where the window itself already provides good isolation and the curtain adds almost nothing. That pulls the average right down.
Why the mid and high range tells a better story
Across 800Hz to 4000Hz — where traffic, speech and most everyday noise actually sits — our curtain adds between 5.4dB and 10.5dB per band, averaging roughly 7dB across that range. This is real UKAS test data, not a rounded-up marketing number.
Frequency by frequency — window baseline vs window with curtain
Lined Acoustic Blackout construction. UKAS-accredited report 80096-SRL-RP-XT-002-P1, Tests 10 & 11.
+2 dB
Certified weighted average (Rw)
across all frequencies
~7 dB
Average improvement at
800 Hz to 4,000 Hz
Where traffic and voices sit
+10.5 dB
Peak improvement at
4,000 Hz
High-pitched sounds
Why does the certified figure show only +2dB? The weighted Rw calculation includes low bass frequencies (below 200Hz) where the curtain adds almost nothing, which pulls the single-number average down. The frequencies where you actually hear the difference — the range where traffic, speech and everyday noise sit — show a considerably stronger result, as the table above shows in full.
Watch before you buy
Our full acoustics guide, plus a real installation working in an office.
Our Full Guide on Acoustics — Absorption vs Insulation Explained
Mimas Acoustic Curtain Working in an Office
Laboratory proven to BS EN ISO 10140-2 / 717-1: +2dB over a double-glazed window and 10dB as a room divider (Lined Acoustic Blackout construction). Works with standard curtain tracks and poles.
Room divider results assume no other obstruction between spaces. If there's already a door or wall doing the work, the perceived improvement from the curtain will be lower.
The face fabric
Hotel-quality Mimas face fabric in 28 colourways, designed to perform acoustically while looking like a premium curtain in its own right.
Absorption
EN ISO 354: Class B lined (0.80αw), Class C unlined (0.65αw).
Fire retardant
Face fabric BS5867 Part 2C, lining Part 2B — assembled curtain rated to the lower of the two.
Colourways
28 colours across all three constructions.
Headings
3" pencil pleat, 44mm eyelet, 60mm wave, 80mm wave.
Want the full technical breakdown?
Download our full spec pack with UKAS lab reports, or read our absorption vs insulation explainer.
Quick reference: a 10dB change is commonly described as sounding roughly half as loud, or twice as loud in the other direction. Your actual result depends on the room, the window or opening, and how the curtain is fitted.
What customers say
Verified Trustpilot reviews from genuine Direct Fabrics customers.
"The wide choice of heavy duty rails helped with getting just what we needed for our very large curtain at the local village hall."
Samantha Lipscomb
✓ Verified · 3 Aug 2026
"Curtain samples turned up very quickly and seemed very high quality."
Stacey Graham
✓ Verified · 29 Jul 2026
"Helpful ordering process. Track arrived promptly, is good quality and as I expected."
Nicola
✓ Verified · 23 Jul 2026
Real installs
Residential rooms, offices, studios, colleges and stages — real Direct Fabrics installations, not renders.
Not sure which construction is right for your room?
Get in touch for a free quotation, free fabric samples, or advice on what will actually work for your space and budget.
Three constructions, one fabric range
Every Mimas curtain uses the same face fabric. What changes is the lining behind it — and that's what determines which of the three constructions below you're getting.
Face fabric alone. 0.65αw absorption, Class C — reduces echo and reverberation. Not designed to block sound transfer between rooms.
Face fabric plus one layer of acoustic blackout lining. 0.80αw absorption, Class B. 10dB as a room divider, +2dB over a double-glazed window (29→31dB). Also blocks light and adds thermal insulation.
Face fabric, acoustic blackout lining, and face fabric again — decorative on both sides, for room dividers viewed from either side. Estimated ~12dB as a room divider based on a closely related tested construction. This build hasn't been independently tested yet; we're committed to getting it lab tested rather than carrying an estimate long-term.
Room divider appearance
If you want a room divider to look finished on the reverse side too, select double sided in the lining options — that's the 3-Layer Double Sided construction above.
Which option is right for me
Three real constructions. Figures marked * are engineering estimates pending independent testing — everything else is UKAS-accredited lab data.
| Feature | Unlined | Lined Acoustic Blackout | 3-Layer Double Sided |
|---|---|---|---|
| Reduce echo | Yes | Yes | Yes |
| Block external noise | No | Yes | Yes (estimated) |
| Colours | 28 | 28 | 28 |
| Blackout | Partial (face fabric only) | Full | Full |
| Hangs as a curtain | Yes | Yes | Yes |
| Heading options | 3" pencil pleat, 44mm eyelet, 60mm wave, 80mm wave | ||
| Reduces road / flight noise* | No | Yes* | Yes* (estimated) |
| Sound absorption (αw) | 0.65 — Class C | 0.80 — Class B | Not independently tested for this build |
| Sound insulation, as room divider | Not tested — not designed to block sound | 10dB, certified | ~12dB, engineering estimate |
| Sound insulation, over a window | Not tested | +2dB, certified (29→31dB) | Not tested |
| Improves acoustics in a studio | Yes | Yes | Yes |
| Compatible with standard pole / track | Yes | Yes | Yes |
*Road and flight noise reduction depends heavily on your room, windows and building construction — see the FAQs below.
- Reduce echo
- Yes
- Block external noise
- No
- Colours
- 28
- Blackout
- Partial (face fabric only)
- Reduces road / flight noise*
- No
- Sound absorption (αw)
- 0.65 — Class C
- Insulation, room divider
- Not tested
- Insulation, over window
- Not tested
- Reduce echo
- Yes
- Block external noise
- Yes
- Colours
- 28
- Blackout
- Full
- Reduces road / flight noise*
- Yes*
- Sound absorption (αw)
- 0.80 — Class B
- Insulation, room divider
- 10dB, certified
- Insulation, over window
- +2dB, certified
- Reduce echo
- Yes
- Block external noise
- Yes (estimated)
- Colours
- 28
- Blackout
- Full
- Reduces road / flight noise*
- Yes* (estimated)
- Sound absorption (αw)
- Not tested for this build
- Insulation, room divider
- ~12dB, estimate
- Insulation, over window
- Not tested
All three: hang as a curtain, work with standard pole/track, improve studio acoustics, and come in 3" pencil pleat, 44mm eyelet, 60mm or 80mm wave headings, 28 colours.
*Road and flight noise reduction depends heavily on your room, windows and building construction — see the FAQs below.
Frequently asked questions about sound proof curtains
Will the curtain stop the road noise entering my rooms? ⌄
Will my curtain stop air traffic noise? ⌄
Which track should I use with my curtains? ⌄
What is the difference between room divider curtains and window curtains? ⌄
What is acoustic absorption? ⌄
What is acoustic insulation / blocking? ⌄
How much difference does a few decibels actually make? ⌄
A 1dB change is almost imperceptible, 3dB is just perceptible, 5dB is clearly noticeable, and 10dB sounds twice (or half) as loud.
| Change in sound level | Change in apparent loudness |
|---|---|
| ± 1dB | Almost imperceptible |
| ± 3dB | Just perceptible |
| ± 5dB | Clearly noticeable |
| ± 10dB | Twice (or half) as loud |
- ± 1dB
- Almost imperceptible
- ± 3dB
- Just perceptible
- ± 5dB
- Clearly noticeable
- ± 10dB
- Twice (or half) as loud
| Sound level dB | Source | Sensation |
|---|---|---|
| 130 | Jet aircraft at 100ft | Physical pain |
| 110 | Thunder / artillery / disco | Deafening |
| 90 | Loud street / loud factory | Very loud |
| 70 | Cocktail party, noisy office, average street noise | Loud |
| 50 | General office, noisy home | Moderate |
| 30 | Private office, quiet home, empty gym | Faint |
| 10 | Rustle of leaves, whisper | Very faint |
| 0 | Threshold of audibility | Nil |
- 130dB
- Jet aircraft at 100ft — physical pain
- 110dB
- Thunder / artillery / disco — deafening
- 90dB
- Loud street / factory — very loud
- 70dB
- Noisy office / street — loud
- 50dB
- General office — moderate
- 30dB
- Quiet home — faint
- 10dB
- Whisper — very faint
- 0dB
- Threshold of audibility
Will my curtains stop sound as a room partition / room divider? ⌄
Will it be fully soundproof? ⌄
How will my curtains perform in a real-world environment? ⌄
Can I return made-to-measure curtains? ⌄
| Washing / Cleaning Information Face Fabric | 71 Degress C, Iron Low Heat, Non Bleach |
|---|---|
| Flame Retardant Certified Rating | BS5867 Part 2B |
| Delivery | Currently 3-4 Weeks - UK Manufactured |
| Flame Retardant | Yes |
| Fabric Style | Plains |
| Fabric Width (cm) | 150 |
| Pattern Repeat Vertical (cm) | 1 |
| Composition | 100% Polyester |
| Features | Flame Retardant, Blackout, Thermal, Soundproof, Acoustic Absorption |
Customer Product Reviews
Top customer reviews
Reviews with images
Images in this review
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A stellar company!This is a fantastic, friendly and helpful company to deal with! Every member of staff I've spoken to has been lovely and very personable. In the days of AI chatbots, it's been really nice to deal with real humans. My curtains came well before I expected them to and have exceeded my expectations having never had custom made curtains before. The material is flawless, the curtains are thick and do exactly as promised- block the light, control the temperature and muffle the sound from the road! Well worth the money for an immaculate purchase. I forgot to add my colour of choice to the order as I was managing a bereavement and a house move simultaneously; I felt like a bit of a fool but the lady I spoke to was so sweet and understanding and also matched my sense of humour which I appreciated greatly. I highly recommend this company, a business that deserves your support and your money! 10/10!0 people found this helpful
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Great customer service;) great product…Great customer service;) great product :)0 people found this helpful
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Supplied and Fitted Acoustic CurtainsBuilding Contractor Feedback and Customer Feedback - name redacted. Shortly after the space became operational, demolition works began on the courthouse directly opposite the building. This has created significant challenges for the company (large plc), as the newly completed office functions as a presentation suite. The noise from the demolition is substantial and vibrations are clearly felt through both the walls and floor. This has led to ongoing discussions with the property agent, as this activity should have been flagged earlier in the process. What this situation has clearly demonstrated, however, is just how effective the curtain solution is. When the curtain is closed and a live presentation is running, the difference is immediately noticeable. The reduction in noise and vibration is not subtle, it is genuinely significant. This applies both to in room presentations and those being broadcast globally at the same time. The feedback from company has been extremely positive. The curtain has proven to be a critical element in maintaining the usability of the space under very challenging conditions, and everyone involved has been impressed by the level of performance it delivers.
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quick deliveryquick delivery0 people found this helpful
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Internal Check Measure FittingProject undertaken in house and installed by Direct Fabrics.
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Direct Fabrics, a super companyFrom initial enquiry through to delivery of the soundproof curtain, everything was spot on. The quality was very good, the price very competitive and delivery was on time. Definitely recommend them.0 people found this helpful
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Direct Fabrics were extremely helpful...Direct Fabrics were extremely helpful in resolving an unexpected issue, and I will definitely use them again.0 people found this helpful
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Mimas Black and White
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