Short answer: Blindspace concealment for an electric roof lantern blind typically costs about £2,300 to £8,700 including VAT, supplied and delivered, for openings from about 1 × 2 m to 3.5 × 6.5 m. That works out at roughly £355 to £420 per metre of box. The roof blind itself is priced separately.
Enter your structural opening below. The estimator shows which electric roof blind systems fit, draws the Blindspace boxes to scale, tells you the ceiling void to form, and prices the concealment line by line. Architects and builders can download a PDF estimate and the Blindspace technical drawing for the chosen system.
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Typical Blindspace concealment prices
These figures come from the estimator above, for one lantern in standard white (RAL 9016, 30% gloss), supplied and delivered to the UK, including VAT at 20%. Blindspace 2026 prices, checked 6 November 2026.
| Structural opening | Roof blind system | Concealment | Boxes fitted | Length of box | Price inc VAT |
|---|---|---|---|---|---|
| 1,000 × 2,000 mm | Venus CTS 85 | 4-sided (head box and tension box) | Beyond the opening | 6.60 m | £2,371.30 |
| 1,200 × 2,000 mm | Athena | 3-sided (hem bar visible) | Beyond the opening | 5.66 m | £2,263.01 |
| 1,500 × 2,500 mm | Athena | 3-sided (hem bar visible) | Beyond the opening | 6.96 m | £2,632.64 |
| 1,500 × 2,500 mm | Athena | 4-sided (hem bar box) | Beyond the opening | 8.72 m | £3,143.58 |
| 1,500 × 2,500 mm | Athena | 4-sided (hem bar box) | Within the opening | 7.74 m | £2,870.63 |
| 2,000 × 3,000 mm | Athena | 4-sided (hem bar box) | Beyond the opening | 10.72 m | £4,062.34 |
| 2,400 × 5,000 mm | Twin Athena | 4-sided (head box at both ends) | Beyond the opening | 15.52 m | £5,487.47 |
| 3,000 × 4,000 mm | Hercules XL Standard | 4-sided (hem bar box) | Beyond the opening | 14.72 m | £5,441.93 |
| 3,500 × 6,500 mm | Hercules XL Max | 4-sided (hem bar box) | Beyond the opening | 20.72 m | £8,658.79 |
Which electric roof blind systems fit
Each system is checked against its size limits using the finished blind size. When the boxes are fitted beyond the opening, the blind grows by the head box, the end box and the side boxes, so a lantern near a limit may need the next system up.
| System | Size limit (width × projection) | Blindspace boxes | Concealment |
|---|---|---|---|
| Venus CTS 85 | Projection up to about 2,500 mm; recommended working size 1,500 × 2,500 mm | C130 × 150 head box and tension box; 50 mm side boxes | Always 4-sided |
| Venus CTS 110 | Projection up to about 3,700 mm; recommended working size 1,500 × 2,500 mm | C160 × 160 head box and tension box; 50 mm side boxes | Always 4-sided |
| Athena | Up to about 3,000 × 3,000 mm or 2,500 × 4,500 mm | C135 × 230 head box up to 3,000 mm projection, C155 × 250 above; 80 mm side boxes; 100 mm hem bar box | 3-sided or 4-sided |
| Twin Athena (two blinds meeting in the centre) | Up to about 3,000 × 6,000 mm or 2,500 × 9,000 mm | C135 × 230 head boxes up to 6,000 mm, C155 × 250 from 6,000 to 9,000 mm; 80 mm side boxes | Always 4-sided (head box at both ends) |
| Hercules XL Standard | Up to 4,000 mm wide × 5,000 mm projection | C155 × 250 head box; 80 mm side boxes; 100 mm hem bar box | 3-sided or 4-sided |
| Hercules XL Max | Up to 4,000 mm wide × 7,500 mm projection, used over 5,000 mm | C190 × 340 head box; 80 mm side boxes; 140 mm hem bar box | 3-sided or 4-sided |
Blindspace technical drawings: Athena under 3,000 mm and Athena over 3,000 mm. Drawings for the other systems are available on request.
How the estimate is worked out
- Beyond the opening: the boxes are built into the ceiling behind the upstand, so the full opening stays clear. The blind is made larger by the boxes, and the builder forms a timber surround to the ceiling void size the estimator gives, plus a 3 mm recess allowance. This is easiest to plan before the ceiling is finished.
- Within the opening: the boxes sit inside the upstand and the blind is made to the opening size, so the visible opening reduces. For a 1,500 × 2,500 mm opening with Athena 4-sided, the clear aperture becomes 1,340 × 2,170 mm, about 78% of the opening.
- 3-sided or 4-sided: 3-sided leaves the blind’s hem bar visible; 4-sided adds a hem bar box to hide it. Venus CTS and Twin Athena are always 4-sided.
- Box lengths: each run includes a 100 mm allowance for cutting on site. Runs over 3 m are supplied in equal lengths joined with splice pins and plates.
- Included: Blindspace boxes with covers and hinges, end caps, splices, a cable grommet, cutting, packing and delivery to the UK (one delivery covers up to two openings).
- Not included: the roof blind, the timber surround, fixings, electrics and installation. A bespoke RAL powder-coated colour is an option.
- Lead time: Blindspace C Series boxes are typically 3 to 4 weeks from a complete order, plus about one week shipping to the UK.
- Status: an indicative estimate, not a quotation. Final sizes are confirmed with you before manufacture.
Terms used
- Structural opening: the inside size of the hole in the roof or ceiling that the lantern or skylight sits over.
- Projection: the direction the blind travels; the head box runs across the width.
- Upstand: the frame or kerb the lantern sits on.
- Head box: the box that hides the blind’s roller and motor.
- Side boxes: narrow boxes along each side that hide the blind’s side guides.
- Hem bar box: a box at the far end that hides the hem bar when the blind is open.
- Tension box: on Venus CTS, the box at the far end that holds the tensioning mechanism.
- Ceiling void: the space formed in the ceiling around the boxes when they are fitted beyond the opening.
Questions
Does the price include the roof blind?
No. The estimator prices the Blindspace concealment only. See how much electric roof lantern blinds cost for the blind itself.
Can Blindspace be added after the extension is finished?
Yes, by fitting the boxes within the opening, which keeps the ceiling as it is but makes the visible opening smaller. Fitting beyond the opening keeps the whole opening clear, but the ceiling has to be formed around the boxes, so it is best planned at design stage.
Who builds the ceiling void?
Your builder or joiner, to the size the estimator gives and the Blindspace drawing for your system. We fit the boxes and the blind.
What colour are the boxes?
Standard white RAL 9016, 30% gloss. Any colour on the standard RAL chart can be powder coated for an extra charge, which the estimator shows.
Next step
Book a free call with a specialist to talk through your lantern, the right blind and the concealment. Useful reading: electric roof lantern and skylight blinds, Blindspace concealed roof blinds, concealing Athena roof blinds with Blindspace and planning the roof structure for internal roof blinds.
