Local Shutter InstallersMyths · Ruling
The myth that any shutter stops heat
Updated
Internal plantation shutters and internal blinds are not external shade. They are good at privacy and moderate at glare.
What is being claimed
The heat in a glass extension needs something outside the pane. The word shutter is doing too much work in UK search results.
The illustration beside the claim
The worked opening for The myth that any shutter stops heat is 0.9 m wide by 1.2 m high, 1.08 square metres of glass. This figure puts 470 watts per square metre on the pane and uses a g-value of 0.76, about 386 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 39 watts and keeps about 347 watts out. That is a noon figure for comparison. An internal blind does not get the same reduction. For The myth that any shutter stops heat, 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.
A night cover is not a consent
Winter figure for The myth that any shutter stops heat: glass at 2.6 W/m2K, 1.08 square metres, a 12 degree inside-outside gap and eight night hours. The bare pane is about 0.27 kWh a night on that crude sum. A closed shutter cutting about 30 percent of the flow leaves 0.19 kWh and saves about 0.08 kWh a night, only while it is down. Open it when you want winter sun.
Paper before manufacture
Stop The myth that any shutter stops heat if the only place for the box is a listed street front and nobody has written advice from the council. A photograph is not a manufacturing size.
Liverpool is only a setting for The myth that any shutter stops heat. The streets there are not the product.
How to use the figure
The 0.9 by 1.2 metre opening inside The myth that any shutter stops heat 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 £1,636. 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 The myth that any shutter stops heat, 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. The myth that any shutter stops heat covers one kind of opening. The house may have three.
When I would not order yet
The myth that any shutter stops heat 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 The myth that any shutter stops heat 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. £1,636 illustrates The myth that any shutter stops heat for a 0.9 by 1.2 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 1.08 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 The myth that any shutter stops heat 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. The myth that any shutter stops heat uses a solar motor in the example so you can see how much the motor choice moves £1,636.