Measuring for Juliets

How to measure for a new Juliet balcony

There’s a lot of jargon out there – openings, recesses, centres, flanges and sills – but you shouldn’t need to be an expert to buy a balcony with confidence.

So we’ve kept things simple; the only measurement you need for a Forjj Juliet balcony is the aperture. This is the horizontal measurement of the structural opening you want to cover with a balcony. Order based on this size (you’ll see below that there are only 6 standard choices) and we will automatically make the balcony slightly wider (around 350mm [or 1ft] overall) to ensure a secure, safe & suitable fit.

Please note: There are some circumstances where you will not want the balcony to be a lot wider than the aperture – most commonly for dormer windows and timber frames – please use the product guide to select the appropriate aperture or just give us a call to check.

Tips for Measuring

  1. Use a metal tape measure as cloth ones can stretch and give you an inaccurate reading.
  2. Measure at 2 different locations [at the base and roughly mid height].
  3. Don’t worry if you get two different measurements. As long as they aren’t wildly different (something is wrong with your tape measure or your building if that’s the case!] use the larger of the two measurement as your aperture size.
  4. Measure twice, order once. It’s best to be confident about the size you are ordering so double-check your measurement or have someone else verify it.
  5. Don’t worry about millimetre accuracy – most window and door openings in the UK are a standard size and you will see below that each balcony design covers a range of aperture values.
  6. If you’re in any doubt about what to measure or what to order, just drop Forjj a line for more advice.

Should I look out for anything else?

Inspect the walls / surfaces to a distance of 1ft (30 cm) around your window aperture. The balcony won’t extend this far, but any obstacles in this area may be important. Look out for any protruding features such as over-sized window sills, drain pipes, electrical cables or stonework that might clash with the balcony frame. Be aware too if you have less than 1ft (30 cm) of space around the balcony area which might cause problems for fixing. Don’t panic if you see any such issues as we can (and have) worked around all sorts of unusual obstacles in the past. Just get in touch or even send us a photograph if you would like any advice.

Which size do I choose?

Apertures do vary slightly so each of our standard Juliet balcony sizes will suit a maximum and minimum aperture range:

I’ve measuredAperture size to orderApproximate Balcony Width
between 890 and 940mm900mm1250mm
between 1190 and 1240mm1200mm1550mm
between 1490 and 1540mm1500mm1850mm
between 1790 and 1840mm1800mm2150mm
between 2090 and 2140mm2100mm2450mm
between 2390 and 2440mm2400mm2850mm
Something else!See belowTo your requirements
I’ve measured: between: 890 and 940mm
Aperture size to order: 900mm
Approximate Balcony Width: 1250mm
I’ve measured: between: 1190 and 1240mm
Aperture size to order: 1200mm
Approximate Balcony Width: 1550mm
I’ve measured: between: 1490 and 1540mm
Aperture size to order: 1500mm
Approximate Balcony Width: 1850mm
I’ve measured: between: 1790 and 1840mm
Aperture size to order: 1800mm
Approximate Balcony Width: 2150mm
I’ve measured: between: 2090 and 2140mm
Aperture size to order: 2100mm
Approximate Balcony Width: 2450mm
I’ve measured: between: 2390 and 2440mm
Aperture size to order: 1200mm
Approximate Balcony Width: 1550mm
Something else!
See below    To your requirements

My measurements don’t match any of your standard sizes?

If your aperture measurements fall outside of these ranges please contact us and we will be happy to help. We can accommodate any other size that you require, sometimes at little or no additional cost.

I don’t have the windows or doors yet, can I order the balcony anyway?

Yes, even if the opening hasn’t been made in the building yet, your window or door manufacturer should be able to advise the aperture size of your new windows or doors and that’s all you need to be able to place your order.

See also our FAQs for more measuring and selection advice.