Measuring a bay window

[gaz_moose]

I Have fitted normal flat windows/front/back doors/french doors and sliding doors so I'm fairly confident i can fit a pair of bay windows. The kind i have are the ones that just stick out with no brickwork below or above, I think some people call them bow windows.

 

The current window bays are a bodge and have some big trims around the edges. so i think they got their measurements wrong so im not going to copy them. When i first moved in i peeled the internal trims off and there was some nice big gaps filled with scrunched up newspaper so i dug that out and foamed them. 

 

Is there a way i can survey them from the outside? like ive done all the other windows/doors ive done.

 

 

 

 

[craig]

Without seeing the outside, it’s impossible to say but do you mean survey as in inspect?

Edited 15 hours ago by craig

[gaz_moose]

Survey as in measure for replacement, 

 

id found THIS  which had me on the right track but then i was stumped on the internal measurement. 

 

I will get a picture later.

[craig]

You should be able to take measurements internally/externally in the same fashion. That diagram is perfect.

 

The internal measurements compared to external will be different and depends on finishes, they could be the same but if brick to brick externally, then I’d expect internal to be slightly smaller as the window measurement will be reduced by the plasterboard (if it is not sitting behind the ingo/check reveal). 
 

I doubt it is a check reveal if you’re in England.

Edited 3 hours ago by craig