FAQs – Top 10 Questions & Answers

1) Why are external blinds more efficient at reducing over heating than internal blinds?

External blinds are installed on the outside of the window and block up to 90% of the solar heat from penetrating the window. Internal shading cannot stop solar gain from penetrating the window.

2) What is meant by the g value when considering external shading?

The G value quantifies the solar heat transmitted through a window, expressed as a number between 1 and 0, where 1 indicates the maximum possible solar heat gain and zero no solar heat gain.

3)Do external blinds allow light and ventilation into the room when closed?

External roller screens offer a choice of mesh fabric with different openness factors (OF), which allow light and ventilation into the room. Soltis 86 fabric has an OF to 14%, allowing 28% of natural light into the room with the blinds closed. Fabrics with a smaller openness factor such as Serge 92 at 4% OF and Serge 600 at 5% OF offer less light and ventilation but better performance against solar gain. Please speak to us and we will be happy to advise you.

Aluminium roller shutters when not fully closed, feature perforations between each slat allowing light and ventilation into the room.

4)What is the wind class of our external blinds?

Our external blinds are guaranteed up to wind class 3 which is equivalent to Beaufort speed 6 or 30 miles/hour equating to a strong breeze. Our zip screens have been successfully tested up to wind class or 50 miles per hour. Motorised screens can be specified with wind sensors which retract blinds and awnings automatically in the box to protect against wind damage.

5)What is the best option to shade bi-folding doors that open outwards?

The best solar shading solution would be a retractable awning, wall  mounted pergola as they allow the doors to be open, maintaining access in and out of the room.

6)What is the best option to shade large sliding doors?

External zip screens up to 6 metres wide work well with large sliding doors as they can be retracted into a small box above the window and the zip seal keep the fabric taut.

7)How can you Install external screens where there is no wall or window frame to fix the side guides?

External screens can be specified with cables instead of side guides. Depending on the location and width of the screen, we would recommend installing a wind sensor with a cable screen.

8)How do manual systems operate from the inside?

The mechanism for the crank is drilled through the wall so that the external blinds can be operated from the inside. There must be enough room by the side of the window for the crank mechanism and the internal wall will require making good. Manual systems cannot usually be fitted in the recess of a window.

9)Are any electrical works required for solar powered screens or shutters?

The beauty of solar powered screens or shutters if that no electrical works are required! The battery is neatly integrated into the box providing an ideal energy saving solution for retrofit installations. Backup batteries are an option should the solar power fail to operate

10)What power supply is required for a motorised external blind?

Each blind requires a maximum power supply of 230V wired into a 13-amp fuse spur or pin plug to connect the motors, which can be specified on the left or right-hand side of the window. Please contact us to find out the precise power supply requirements for your project.

11)What maintenance is required for external blinds?

Our products are designed and manufactured with durable materials to last for many years with a minimum of maintenance.

The aluminium profiles should be cleaned at least once a year with warm water, soap or detergent and a sponge or rag. Avoid using chemical cleaning agents and all types of abrasives which could damage the surface of the blinds.

Spray silicone should be used to lightly oil the profiles taking care not to stain the screen fabric.

Screen fabrics are treated with a special dirt shedding product but dust deposits may accumulate over a period of time. Dust may be brushed away with a paintbrush or soft bristle hand brush, blown away using filtered air with no trace of dampness or gently sucked away using a low airflow vacuum without rubbing the suction nozzle on the screen.

Any dirt deposits of tree sap, bird droppings or dead insects which stick to the screens, should be cleaned with mild soapy water. Specialist cleaning products are also available from Serge Ferrari.

Inspect the blinds several times per year to check for the following:

Increased noise when being pulled up or dropped down

Uneven raising or dropping of the blind

Visibly compromised condition of textile straps or ladders

Loose screws in the side guides

Please contact us if you need any further advice.