Local Shutter InstallersSystems · Survey
Box sizes from about 137 mm upward
Updated
Boxes grow with the curtain height and the slat. Common cassettes step through sizes around 137, 150, 165, 180 and 205 mm, and security or tall doors go larger.
Sun, in watts
The worked opening for Box sizes from about 137 mm upward is 1.2 m wide by 2.1 m high, 2.52 square metres of glass. This figure puts 545 watts per square metre on the pane and uses a g-value of 0.76, about 1044 watts into the room if the curtain is up. An opaque external shutter, taken as stopping 90 percent of that gain while it is fully down, leaves about 104 watts and keeps about 940 watts out. That is a noon figure for comparison. An internal blind does not get the same reduction. For Box sizes from about 137 mm upward, use the noon figure to compare two openings on the same house, then let a measured survey replace the figure.
An internal blind does not get that reduction, because the energy has already crossed the glass.
On this opening
A soffit that only has 140 mm will not accept a polite fiction. Measure the soffit before you fall in love with a tall door curtain.
The same glass in winter
Winter figure for Box sizes from about 137 mm upward: glass at 2.6 W/m2K, 2.52 square metres, a 12 degree inside-outside gap and eight night hours. The bare pane is about 0.63 kWh a night on that crude sum. A closed shutter cutting about 30 percent of the flow leaves 0.44 kWh and saves about 0.19 kWh a night, only while it is down. Open it when you want winter sun.
I would not order yet
Stop Box sizes from about 137 mm upward if the solar panel would sit in a soffit with no sky, and the quote has no wired alternative. A photograph is not a manufacturing size.
Nottingham is only a setting for Box sizes from about 137 mm upward. The streets there are not the product.
How to use the figure
The 1.2 by 2.1 metre opening inside Box sizes from about 137 mm upward is there so a quote has something to disagree with. If the tape gives a different size, the tape wins.
The example drive is a solar motor, and the illustration is £2,246. A belt, a wired motor and a solar motor can share a curtain and still be different jobs. Compare those lines, not a single bold total.
What the survey still has to write down
For Box sizes from about 137 mm upward, ask where the box lands, what colour reference will be ordered, and how the curtain opens when the motor is dead. Those three answers move the job more than a rounded price.
Leave the lantern, the side light and the next elevation off the order unless they are drawn. Box sizes from about 137 mm upward covers one kind of opening. The house may have three.
When I would not order yet
Box sizes from about 137 mm upward should wait if the opening is an escape door with no way to raise a dead motor, or if the front is the elevation a conservation area was drawn to protect.
A photograph is not a manufacturing size. Two quotes for Box sizes from about 137 mm upward only compare when the slat, the box and the drive are the same kind of thing.
Questions worth asking the fitter
Is the price on this page a quote?
No. £2,246 illustrates Box sizes from about 137 mm upward for a 1.2 by 2.1 metre opening with a solar motor, at September 2026 rates. Your survey replaces it.
Does the shutter cover every pane?
It covers the opening it is built for. Here that example is 2.52 square metres. A roof lantern, a side light or the next elevation is another line.
What if planning is unclear?
Do not pay the factory for Box sizes from about 137 mm upward until a listed building, a conservation front, a flat or a shopfront has a written answer. Ordinary rear walls on houses are sometimes simpler.
What should two quotes share?
The same openings, the same slat type, and the same drive. Box sizes from about 137 mm upward uses a solar motor in the example so you can see how much the motor choice moves £2,246.