We get lots of enquiries about finding the right size lampshade for your lamp base ā and we try and give information on the website to help you do that but sadly, this is not an exact science.
However I am going to try and give some advice here to help you along the way.
It may sound obvious but the easiest and best way to be sure is to find an existing shade in your house and try it for size! This may not be possible so you might try cutting out a shape on paper or card and holding it up on the lamp.
The critical measurement in a lampshade is the diameter of the bottom of the shade. As a rule of thumb ā for all lamp bases except very thin ones ā such as our candlestick , the height of the lamp base to the base of the bulb holder should roughly equal the diameter of the bottom of the shade. And ideally the shade should be at least Ā½" wider than the base.
As I have said, this does not apply to very narrow table lamps where you will want a shade roughly a half to two-thirds the height of the base.
And the height of the shade should be approximately three-quarters the height of the base.
Another thing to think about is how high you want the shade to sit on the base.
Since all of our larger shades (everything 14ā or more) are made with a Duplex fitting, this gives you some flexibility ā as shown in the picture. Here are 3 different sized shades sitting on the same table lamp ā in Picture A we have a 14ā sitting on a 5ā shade carrier; in Picture B we have a 16ā sitting on a 6ā shade carrier and in Picture C the shade is 18ā sitting on a 7ā carrier.
Generally we recommend the following size ratio of shade carrier to shade:
5ā to 14ā (35cm)
5ā to 16ā (40cm)
6ā to 18ā (45cm)
7ā to 20ā (50cm)
9ā to 24ā (60cm)
In the end the size of shade is dictated by personal preference, the height of the article of furniture it sits on and the size and style of the room. Large, high ceilinged rooms will take a large shade but if your room has a low ceiling you need to go for something smaller.
As for Floor Lamps ā they will usually require at least a 45cm shade ā although again you may find that a smaller shade will work in a more contemporary setting.
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