External French doors

External French doors are usually used where a doorway opens out to a garden, patio, or similar area. They are hinged glass doors, where patio doors are glass doors which open with either a sliding or folding mechanism. They are designed to allow plenty of light through them.

They are usually double doors, but occasionally they will be a single leaf. They can be installed to open either inwards or outwards. Sometimes they have static panels, which are used to replace wall sections, so light can pass through them. The glass can be frosted or textured to increase privacy, or you can fit blinds or curtains.

Any glass used in external doors needs to comply with certain building regulations for safety and insulation. They can be a point in your home which is vulnerable in terms of security and insulation, more so than some other external doors. Wonkee Donkee XL Joinery supply top quality external door frame sets  for easy installation of beautiful French doors.

How is an external French door constructed?

French doors are usually fully glazed doors, meaning the majority of the door leaf is glass within a solid frame. Some French doors have some solid panels as well, depending on the specific design of the door. 

Traditional French doors were made up of many individually framed glass panels joined to form the door's leaf. This is an expensive process, so most modern french doors use a large single glass panel which can be decorated with glazing bars. This gives the appearance of separate panels. The downside to this construction is that the entire panel needs to be replaced if there is a breakage in the glass. 

French doors use a panel and frame construction, with stiles either side and rails at the top and bottom framing the glass. The glass is held in place with glazing bars. The door hardware is fitted to the frame around the glass.

What can external French doors be made of?

French doors can be made using different types of glass, which can create various effects. You need to make sure an appropriate grade of glass is used for an external door. The frames of French doors can be made of various materials, with different finishes available, depending on the desired look you want and what properties the doors should have. 

Glass 

The glass used to make external French doors needs to be suitable for use in external applications or the door will be a key point of heat loss and a security risk. There are a number of different grades of glass that can be used, including single, double and triple glazed. You will need to weigh up which glass offers the best properties for your budget. 

If you're planning on fitting French doors somewhere that's exposed to direct sunlight you might want to consider glass which is coated or tinted to prevent things like carpets and pictures from fading in the sunlight.

What can external French door frames be made of?

The material used to make the frames of external French doors will affect their strength and insulation properties, as well as the overall look of the doors. Some French external doors will have different materials used for external and internal parts, due to the different atmospheres each side is exposed to. This means you can achieve a different look either side of the door.

Wood

The most traditional material for doors is wood, and it's generally considered to be the most attractive. They can be painted or stained to achieve different looks, but these finishes need to be regularly maintained.

Different species and types of wood can be used for French doors, so you'll need to check the exact type of wood being used to ascertain what properties it will have. Woods can warp or rot when exposed to the weather so some external doors will have wood on the inside, and will be clad with another more durable material on the outside.   

Natural woods are usually the most expensive, but this depends on the type of wood used; the higher the quality, the more expensive the doors will be. Wood can also be used as a veneer over less expensive materials. This gives the look of wood with less of the cost, but these need to be fixed with appropriate adhesives and may peel over time.

The advantages and disadvantages of wood 

ADVANTAGES

DISADVANTAGES

• Looks attractive

• Expensive natural wood veneers can easily be applied to other materials

• Can be stained, or painted, and can come ready finished

• Good insulation properties

• Can be expensive

• Requires more maintenance than other materials

• Can be prone to warping and rot if it does get wet

• Needs to be sealed on all edges with appropriate paint or stain

uPVC

uPVC, or vinyl, is often the cheapest option for French doors, and it has a lot of excellent features for external applications. uPVC is also commonly used for window frames, so it may be a uPVC door will match well with the rest of the outside of your home. 

uPVC has excellent insulation properties and can be used as a cladding for wood. It's generally long lasting and requires minimum maintenance. However, it's not considered to be very visually appealing, and the standard will always be white; other colours and woodgrain finishes will make the doors more expensive.

The advantages and disadvantages of uPVC

ADVANTAGES

DISADVANTAGES

• Usually one of the cheapest options

• Easy to maintain

• Excellent thermal insulation 

• Won't rot, peel or flake

• Changing door hardware or the finish will be difficult or even impossible

• uPVC will not last quite as long as most other materials

• Extreme temperature shifts can cause it to crack

• Not considered attractive

Aluminium

Aluminium is strong and durable, but relatively lightweight. It requires little maintenance as it naturally resists corrosion. This makes it useful as a cladding for wood, when installed on the external side of the door. 

It's not considered to be as visually appealing as wood, but can be coated in various colours. Aluminium frames will have a thermal break, which increases its insulation properties, but the metal itself can get very hot or cold when the temperature changes. 

The advantages and disadvantages of aluminium

ADVANTAGES

DISADVANTAGES

• Tough and durable

• Naturally rust resistant, and usually protected with an anodised finish

• Lighter than steel and fibreglass

• Available with various finishes

• Won't look as elegant as natural wood

• Can be prone to denting, especially on corners as aluminium welds are not as strong as steel ones

• Can have weak weld joints

Fibreglass 

Fibreglass, or GRP (glass reinforced plastic), can be one of the most expensive frame materials, but the quality varies quite a lot between different manufacturers. Cheaper fibreglass doors will be lower quality and not as durable.

It's often used as a composite with other materials which combine to provide optimum properties, although these enhancements will make the door more expensive. It has particularly good insulation properties and is available in a number of finishes including wood grain effect.

The advantages and disadvantages of fibreglass 

ADVANTAGES

DISADVANTAGES

• Very durable and resists denting

• Resistant to moisture and won't peel, swell, or warp

• Requires very little maintenance

• Available in many different colours and with various finishes, including wood grain

• Excellent thermal insulation properties

• Can crack under severe impact and is very difficult to repair

• There is a big difference in the quality of individual fibreglass doors; high-quality fibreglass is expensive

• Cheaper versions are painted, rather than having the colour all the way through them; this shows scratches

• It won't be expected to last as long as a solid wooden door

Steel

Steel frames are usually the strongest, but also the heaviest, which can make them difficult to install. The steel used needs to be treated to make it resistant to rust, and the different treatments will vary in durability and cost. This does mean it can rust if it gets scratched and isn't retreated to protect it. 

Steel can be used to strengthen other materials, such as wood, which is more common than having a solid steel frame. If it is maintained properly it should be a long lasting material. It needs to have a thermal break to improve its thermal properties, although the metal itself will be affected significantly by temperature change. 

The advantages and disadvantages of steel 

ADVANTAGES

DISADVANTAGES

• Won't warp or crack

• Offers excellent protection against the elements and any rough treatment

• Steel doors will be durable and long lasting

• They are available in many colours

• Even when they are finished they won't be as attractive as natural wood 

• Steel is heavy and can be difficult to install

• Needs to have a thermal break to improve insulation properties

• Can be prone to rust if scratched and not immediately repainted

• Can dent and is difficult to repair