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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:
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Lower U-value limits for both new and existing homes
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Mandatory background ventilation
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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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THRESHOLD
Choosing your threshold
best deal windows composite doors come with three different threshold styles which are suitable for different applications. An ultra low threshold measuring only 15mm high, a slim pvc threshold measuring 52mm and a full pvc threshold measuring 72mm. Choosing the right threshold for your new best deal windows composite door will ensure you are happy with your choice for years to come.
uPVC composite door thresholds?
A threshold for traditional uPVC doors is located at the foot of the door itself to provide a weather tight seal from the elements. In previous years, uPVC door thresholds featured a solid piece of outerframe that went around the entire door, meaning you had no options but to step over a piece of plastic to gain entry to your home through the front door or back door.
This was considered awkward for many homeowners over the years, but against the benefits of dramatically increased thermal efficiency over timber doors many opted for the threshold.
since the introduction of composite doors many homeowners can now benefit from the convenience of a low aluminium threshold, but with excellent thermal efficiency properties due to new technology.
There are 3 different threshold options to choose from for Best Deal Windows Composite Doors. 1, Low Aluminium (suitable for open-in and open-out doors), 2, Slimline PVC or 3, Full PVC.
What to consider when choosing a threshold?
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U Value & Thermal Efficiency
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whilst all thresholds provide excellent thermal efficiency inline with building regulations, the lower u-values can be found with the full PVC threshold.
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Functionality
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You may require the convenience of a Low Aluminium Threshold if you need disabled access, or if you need to take a pram in and out for example. It also prevents you tripping over the door threshold when entering the front door or back door.
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Flooring height
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different thresholds are suitable for different applications. Very often flooring heights will dictate what type of threshold is right for your property which your installer may highlight.
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Flooring style
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again different thresholds suit different floor styles, so please talk this through with your Best Deal Windows installer.