Help calculating if my patio doors are too big for the room

[Rowanm]

Hi

Can someone help me calculate whether or not my patio door will be too big for a room - as per building reg L1 maximum glazed area must not exceed 25% of floor area.

Room width - 4650 mm
Room depth - 2600mm (this is measured into the window sill)

Size of glazed unit 3016mm

Please Help

 

[Robert too]

add up the area of glazing that the extension will cover up , ie old windows and doors that previously led to the outside air.

Now add your 25% of the proposed additional floor area , the combination of the 2 totals is the amount of glazing you can have in your extension.

If that struggles , then work out the floor area of the entire house , and assuming the existing house is double glazed , then you can have a total of 25% of the entire house area as glazing throughout the property.

 

[Rowanm]

Thanks, but this is existing space, not a new extension, so not sure if I can take into account the window and door that this new larger patio door will be replacing?