Steve Bromberg of Express Bi-Folding Doors outlines the essential factors for self-builders who are considering sliding doors – from size limitations to energy efficiency
OTHER THAN SAVING SPACE, WHAT BENEFITS CAN SLIDING DOORS OFFER OVER BI-FOLDS?
The main benefit of sliding doors over bifold alternatives is the overall aesthetic when the doors are closed. Due to the technology of the mechanism, sliding door panels are generally larger, meaning more glass and less frame. This is obviously a benefit for those consumers looking to sliding doors for showcasing their view, as it means that the outside will not be completely obscured by the frame. Also, because of how sliding doors are manufactured the frames are always a lot slimmer – another reason why they’re increasing in popularity.
WHAT MATERIALS ARE FRAMES AVAILABLE IN, AND HOW THIN CAN THEY BE?
Materials are available in PVCu and timber, but the real benefits are seen in aluminium. Sightlines vary considerably but frames slimmer than 40 mm are quite standard and some go as slim as 21 mm. Some manufacturers offer a glass sliding door with a completely concealed frame and a visible sightline of just 25 mm – this means you have large pieces of glass literally separated by only 25 mm of profiles – this is becoming a very popular solution, as it fulfils the needs of consumers, both practically and visually.
IS THERE A LIMIT ON HOW LARGE I CAN GO?
When it comes to size limitations, it varies entirely on the system. However, as a general rule of thumb we recommend keeping each individual glass panel less than 5 m2. The reason for this is because glass within that size can be 6 mm toughened. If 5 m2 is exceeded then the glass needs to be 8 mm toughened both sides. This is very heavy and expensive, as well as bringing logistic and access issues – it’s doable, but at a premium.
WHAT OTHER DESIGN OPTIONS ARE AVAILABLE?
There is a wide range of top-quality sliding doors available on the market, offering a variety of styles. The designs which boast the slimmest frames are the slim-line bonded sliding doors, while there are also slim-line products available that have been created specifically for patio doors, as well as lift and slide doors. Doors are generally available with two, three, four, and six panels, so there are plenty of options including a triple track with three panels which allows for a 66 per cent clear opening, or even a quadruple track which allows for four panels and a 75 per cent clear opening – a great solution for really wide openings.
HOW ENERGY EFFICIENT ARE SLIDING DOORS?
Due to the reduction in framework, sliding doors are generally more thermally efficient than bi-folding doors. With the doors being predominantly made from glass, as long as a highquality, low emissivity glass is used in the installation, the doors will be very thermally efficient.
ARE THEY ‘USER-FRIENDLY’ I.E. NOT TOO HEAVY TO OPEN AND CLOSE?
Panoramic sliding doors can be heavy because the weight of the glass is directly on the rollers – this is another reason why you shouldn’t be too ambitious with the size of the panels. Lift and slide doors alleviate this problem as the mechanism lifts the glass slightly, making them much lighter and easier to slide. Lift and slide doors are perfect for really big doors, and are popular with elderly couples and family homes with young children.
WHEN IT COMES TO INSTALLATION, WHAT POTENTIAL ONSITE ISSUES ARE THERE AND HOW CAN THESE BE OVERCOME?
The biggest potential issue which arises is access. There is demand for bigger and bigger glass, but this must be placed near the door opening safely, which is difficult on a building site. In terraced houses in London for example, sometimes a crane is the only way to do this. The tracks on sliding doors are a lot deeper than standard doors, so it’s never a simple task to remove existing doors to replace with panoramic sliding doors. The doors need to be installed onto a solid base as they’re so heavy you can’t have the bottom track floating over a cavity. These issues can be overcome by dealing with professional companies who are experts in their field, and can offer sound advice at every step. The company installing the doors will carry out a full site survey to root out the potential issues and find workable solutions.
HOW LONG WILL INSTALLATION TAKE?
It depends how big the doors are, but generally a sliding door should be installed in a few hours.
ARE THERE ANY OTHER CONSIDERATIONS TO BEAR IN MIND?
Like any construction job, there are various factors to consider. The number of panels is a big consideration as well as the practically of the doors. Safety must always be your first consideration, for example, floor to ceiling glass doors look great, but you have to be wary of children playing in and around them. As well as safety, there are the obvious logistical obstacles to overcome. Things such as considering the level thresholds from inside to out. These are a key requirement, so it is important for clients to pick their door products early in the project so they can prepare the site properly for their installation.
Steve Bromberg is managing director at Express Bi-Folding Doors