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ENERGY EFFICIENCY & U-VALUE PERFORMANCE
At Best Deal Windows, we proudly supply and install window and door systems manufactured with the highest industry standards. Partnering with Selecta Systems, we offer Eurolook70 profiles combined with Thermaglas sealed units to deliver exceptional thermal efficiency and compliance with current UK Building Regulations.
Our multi-chambered window and door profiles, in combination with 40mm triple glazing (TGU) or 28mm double glazing (DGU), can achieve U-values as low as 0.8 W/(m²K). These performance levels help homeowners reduce energy bills, improve comfort, and meet sustainability targets.
DOCUMENT L — Future Homes Standard Compliance
Our products fully comply with Document L, ensuring energy efficiency standards are met for both new and existing homes.
New homes now require:
✓ Windows: U-value ≤ 1.2 W/(m²K)
✓ Doors: U-value ≤ 1.2 W/(m²K)
For existing homes:
✓ Replacement windows must meet at least 1.4 W/(m²K)
✓ Replacement doors (with >60% glass) must also meet at least 1.4 W/(m²K)
DOCUMENT F — Ventilation Requirements
As of June 2022, homes must have background ventilators with trickle vents unless other adequate systems exist.
✓ Kitchens/Living Rooms: 8000mm² (2 EA)
✓ Bathrooms/Toilets: 4000mm² (1 EA)
Stricter requirements may apply where natural ventilation is limited.
2022 BUILDING REGULATION CHANGES
As of 15 June 2022, updates to Part L and F require:
-
Lower U-value limits for both new and existing homes
-
Mandatory background ventilation
-
Full compliance with carbon efficiency targets
SUPPORTING THE NET ZERO 2050 GOAL
Best Deal Windows is committed to the UK government's goal of achieving net zero carbon emissions by 2050. By offering energy-efficient windows and doors, we help reduce overall carbon impact, support sustainable building practices, and future-proof properties against tightening regulations.
WHY CHOOSE US?
✓ A-rated systems with U-values as low as 0.8
✓ Fully compliant with Document L & F
✓ Expert installation with technical support
✓ Ideal for new builds and renovations
✓ Environmentally responsible solutions
📞 Contact us today to discuss your project requirements or request technical documentation.
At Best Deal Windows, we proudly supply and install window and door systems manufactured with the highest industry standards. Partnering with Selecta Systems, we offer Eurolook70 profiles combined with Thermaglas sealed units to deliver exceptional thermal efficiency and compliance with current UK Building Regulations. Our multi-chambered window and door profiles, in combination with 40mm triple glazing (TGU) or 28mm double glazing (DGU), can achieve U-values as low as 0.8 W/(m²K). These performance levels help homeowners reduce energy bills, improve comfort, and meet sustainability targets. [...]DOCUMENT L — Future Homes Standard ComplianceOur products fully comply with Document L, ensuring energy efficiency standards are met for both new and existing homes.New homes now require:
Windows: U-value ≤ 1.2 W/(m²K)
Doors: U-value ≤ 1.2 W/(m²K)
For existing homes:
Replacement windows must meet at least 1.4 W/(m²K)
Replacement doors (with >60% glass) must also meet at least 1.4 W/(m²K)
DOCUMENT F — Ventilation RequirementsAll replacement and new-build installations follow Document F, which requires background ventilation to ensure healthy air flow:
Trickle vents must be fitted regardless of whether existing windows had vents
Minimum vent sizes per room type:
Kitchens/Living Rooms: 8000mm² (2 EA)
Bathrooms (with or without toilet): 4000mm² (2 EA)
For new homes with natural ventilation, stricter requirements apply based on layout and air tightness.--- 2022 BUILDING REGULATION CHANGES As of 15 June 2022, updates to Part L and F require: - Lower U-value limits for both new and existing homes - Mandatory background ventilation - Full compliance with carbon efficiency targets Our windows and doors are manufactured in line with these updated standards, helping customers stay compliant while reducing energy use. --- SUPPORTING THE NET ZERO 2050 GOAL Best Deal Windows is committed to the UK government’s goal of achieving net zero carbon emissions by 2050. By offering energy-efficient windows and doors, we help reduce overall carbon impact, support sustainable building practices, and future-proof properties against tightening regulations. --- WHY CHOOSE US? ✔ A-rated systems with U-values as low as 0.8 ✔ Fully compliant with Document L & F ✔ Expert installation with technical support ✔ Ideal for new builds and renovations ✔ Environmentally responsible solutions Contact us today to discuss your project requirements or request technical documentation.
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TRANSOM OPENING WINDOWS





This is the horizontally operating application of single opening windows. The hinges are connected to the horizontal part of lower sash. The handle is on the upper horizontal part The handle is in closed [normal] position while it is parallel to the ground, namely, horizontal. The handle Is opened by being turned in downward position, by turning the sash on the axis of hinges on lower horizontal part. A transom switch is available on the side of the sash so that the profiles or hinges are not damages due to the fully turned [180°] sash hitting the wall or being strained. The switch will allow the sash to be opened to a certain extent Switches that accommodate different opening sizes can be used in line with the magnitude of the joinery or customer's preference, the locks that are closed with a strike can also be used instead of handles. To close the window, it is enough to hold it by the handle and push the sash towards the frame, then turn the handle once the sash has been secured in the frame. Sometimes, double switches can be used in especially large size transom windows. Assisting with the other hand while closing transom joineries that are large and in different forms [triangular, round, elliptical, trapezoid, etc.] will be beneficial in terms of the functionality and lifetime of the mechanism. For stricken lock applications, the closure of the window is performed by pulling down the latch of the lock and pushing the sash [then, immediately releasing the latch]. It is enough that you pull down the latch of the lock and pull the sash towards yourself while opening the sash. When it is intended to set the sash released for cleaning purposes, the transom switch pin is removed from its slot while the sash is semi-open, then the sash is slowly released downwards. The window is cleaned after necessary precautions to ensure that the sash, hinge and mechanism are not damaged have been taken. After cleaning, make sure that the switch is secured in place and the system is operating smoothly.
If the transom windows are outside the range of reach, namely, if they are high above [garage windows, factory windows, etc.], then a different accessory is used. There is no handle on the sash in this application which is called high transom. The transom sash and espagnolette are activated by means of a different mechanism. This mechanism, which extends downwards from the side of the high transom window as being built in the wall ensures that the high transom window is opened and closed by means of a special mechanism handle fixed on the wall that will ensure convenient control from the ground at the normal distance of an arm. The high transom mechanisms enable simultaneous control of multiple transom windows. If necessary, the same mechanism is also used in reverse transom systems. Multiple high transom applications can also be implemented on condition that they are one on top of another or side by side.