What is the purpose of a back door?
As well as being the secondary entrance to your house, the back door is also the main entranceway to the back yard or patio, which may be a feature you want to play up! These doors come in all sorts of styles to suit all kinds of exteriors; it doesn’t matter if your back yard is a feature or a folly. Back doors should be secure too, especially if your yard is facing a busy street, or if your yard backs onto an alleyway, a park or some other area that's open to the public.
What qualities should a good back door have?
If you have a nice, scenic back yard, the back door will ideally provide a panoramic outlook to your yard, decking or patio, giving you unobstructed views when open or closed. This will help both to give your living areas a greater sense of space, and to introduce natural light into your home.
Likewise, regardless of what type of door you choose, it should also have good weather protection and thermal insulation and should offer the same amount of security as your front door does (i.e. solid construction, deadbolt if appropriate).
What sort of doors are appropriate for back doors?
Contemporary home designs generally 'integrate' the back yard, rather than trying to hide it like older homes did. Large glass panel doors such as sliding doors, stacker doors and convertible bi-fold doors are popular these days, especially to lead out onto decking or a patio. These doors most commonly come with timber frames, although this is largely a matter of taste.
It'll really depend on the design of your home, of course - if you've got a fairly plain view out the back (or if your house backs onto an alley) then you may well feel more comfortable with a good solid timber door instead.
What materials are appropriate for back doors?
If you are considering big glass slider, stacker or bifold doors, you should also consider how much heat the glass panels and framing will let in or out of your home, both through the glass panels and through the frame (particularly metal frames). Glass doors are effectively large windows, and they can be responsible for a significant amount of unwanted heat transfer. Double glazing, solar window films, low-e glass and sensible shading can all make a difference - as will less conductive frame materials (wood's pretty good in this respect)!
For more modest back doors, a solid hinged door will do the job. Back doors often have screen doors attached too, to allow them to stand open and still keep insects at bay. Back doors should be secured just as well as front doors, and should ideally have a deadbolt installed.
