Bi-fold doors are increasing in popularity, with the market expected to grow by 7% year on year. Their aesthetically pleasing modern design lightens up a room, creating an enviable inside and outside space. The installation of bi-folds also has the power to increase a property’s value by as much as 10% – it’s no surprise they’re so sought after! While bi-fold doors are a sleek home addition, with the average large format doors filling an aperture of over 3.5m wider and 2.1m high, product quality and air tightness are incredibly important. It is recommended to review the doors energy efficiency before purchasing. Less energy efficient models that let in a draught will let heat out of a property and won’t be as protective of the interior.
Here’s what you should look out for in order to identify an energy efficient bi-fold door system:
The U-value measures how effective a material is as an insulator. As a rule, the lower the U-value, the more efficient the material and therefore, the lower the annual energy bill will be. With bi-folding doors you generally want a value of 1.4 or less to ensure that you have optimal thermal performance. There are a variety of energy efficient bi-folding doors, with low U-values, such as bi folding doors from Quickslide.
- Weather Testing
A suitable weather resistant bi-folding door should have been rigorously tested to ensure they are watertight and remain protected against an array of weather conditions. Bi-fold doors are subject to a weathertightness test, more formally known as a BS6375 Part 1. This assesses the air permeability (varying levels of air pressure are applied to the material, testing the amount of air leakage), water tightness (water is sprayed at varying pressures to see at what point it starts to penetrate) and wind resistance (varying levels of wind pressure are applied to see what the maximum resistance levels are). When purchasing a bi-folding door, make sure to check the exact model has undertaken a weathertightness test. This will offer homeowners peace of mind that the doors will keep their home fully insulated from all weather conditions.
- CE Marking
CE Marking is a legal requirement for products sold in the European Economic Area. It is mandatory for all UK manufactured bi-folding doors to be CE marked. For a product to receive this accreditation, the manufacturer must present evidence under a series of categories, including thermal efficiency and weathertightness. Therefore, you can rest assure that any door you are purchasing with this marking, will be compliant with required performance characteristics, in line with UK requirements, such as weathertightness and thermal.
- Polymide Thermal Barrier
Aluminium is a natural conductor, so to improve the insulation of the door frame, they can be upgraded to include polymide thermal barrier technology. Aluminium bi-folding doors that have been upgraded to this technology over old resin thermal barrier give at least a 30% improvement to thermal efficiency. The advanced profile technology creates a thermal transmittance barrier between the cold outside and the warm inside. This works to thermally secure the home, keeping it warm in the winter months, and reducing the energy bills.