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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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BI-FOLD DOORS
Add the wow factor to your home Imagine being able to open up an entire wall of your room, creating space and letting fresh air and natural daylight flood into your home.
Whether you have a bedroom with Juliette balcony, a dining kitchen, a conservatory or an orangery, bi-folding doors can provide a stunning alternative to patio or French doors.best deal windows bi-folding doors were the first fully bespoke PVCu bi-folds to be designed, engineered and made in the UK – and we believe they are still the best. Available in a wide choice of opening configurations and colours, your best deal windows bi-fold has ultra-slim sightlines, providing your room with a clean, modern appearance.
Safety features include the innovative low threshold option for family friendly and wheelchair use. What’s more, the best deal windows bi-fold offers high energy efficiency, combined with the best security features on the market – bringing you a modern space- saving solution for your home that will definitely give it the ‘wow’ factor.
One of the most effective ways you can save energy within your home is through installing energy efficient windows, doors and roofs. best deal windows frames outperform most of the other leading brands in the UK when it comes to thermal efficiency – mainly due to our innovative PVCu multi-chambered profile design. The thermal efficiency of a door is measured in U-values, which demonstrate how effective the door is at preventing the transfer of heat into and out of a building. The lower the U-value, the higher the doors’ effectiveness at keeping the heat inside your home when it’s cold outside. The standard best deal windows bi-folding door range can achieve a U-value of 1.3 W/m2K when fitted with cost effective double- glazed units, which means you’ll be able to enjoy a warmer and quieter home as well as lower energy bills. And for even greater thermal efficiency, the best deal windows ModLok bi-folding range can be fitted with triple glazing, reaching an impressive U-value of 1.0 W/m2K
The best deal windows bi-folding door range is beautifully designed for modern living.
Built to create the perfect summer ambience, it’s equally as important that our doors withstand the worst of the British winter weather. We’ve rigorously tested our bi-folding doors to make sure they exceed the appropriate British Standards for weather performance. We also subject our doors to a regime of robot cyclic testing in our purpose-built laboratory, making sure all mechanical parts will stand up to the repeated operation necessary for daily living.
Your home, your choice The best deal windows range offers complete flexibility, whatever the room or the size of opening you need.
Manufactured in our decorative sculptured profile, best deal windows bi-folding doors are available in a wide variety of colours. With options from two to seven panes, all with our beautiful, super-slim sightlines, you can also choose how many doors fold back to each side of the frame. The best deal windows standard bi-fold door range is available in a wide range of configurations whilst the best deal windows bi-folding door range offers an even greater number, due to its additional strength and rigidity (see full table opposite).
Combining aluminium reinforcing within the bi-fold doors and frame with a high security locking mechanism, the best deal windows bi-fold offers all the structural benefits of an aluminium door set combined with the thermal benefits of PVCu – bringing you the best of both worlds. Our door pane numbering works like this:
• The first number shows the number of doors in total within the frame.
• The second number shows the majority of doors folding back to either left or right. • • The third number shows the balance of doors opening in the opposite direction.
A brand new concept in locking technology, best deal windows has been developed by best deal windows to enable even wider door configurations.