What is a dado rail?
In architecture, the lower part of the wall above the skirting board is called the dado, and the dado rail sits just above this.
The diagram below shows the classical origins of interior architectural mouldings and how they represent the classical order.
The dado represents the die (also known as a dado) in classical architecture which sits above the base of the pedestal.
In pre-industrial design books, the dado rail was called the dado or the wainscot cap. The term "chair rail" only came later.
A little history
Before the 18th century, chairs and other pieces of furniture were only moved into the middle of the room when it was being used. The furniture stayed against the walls when it wasn't being used, so that the centre of the room was empty most of the time. There is a wonderful example of what this would have looked like at Blickling Hall.
These wall-hangings are exact reproductions of the original 1779 silk-damask hangings that originally covered these walls. The dado rail with the dado below were used to protect the very expensive wall coverings from being damaged by the furniture.
How do I restore my dado rail?
Where the dado rail is still in its original place and it's in fairly good condition, then it's definitely worth restoring. If the dado rail has been previously removed, and you'd like to replace the original, remember the following:
If you can see where it has been removed, replace the rail at the same height. Look for bumps or old fixing holes in your plaster-work to determine the original height.
Do not place the dado rail too high, this can make the whole room feel wrong. Some carpenters will give you a specific height, or advise you to divide the height of the wall in three and fit the rail a third up the wall. I've even heard someone say that you should measure the back of your chairs to determine the height of your chair rail. The simple answer to this question is that there is no set rule. There cannot be a "one size fits all" rule to tell you where to put your chair rail because it all depends on the ceiling height. It's all about proportion. The dado rail should fit proportionally into the room, so let your ceiling height guide you.
If I don't have any architectural features left in my period house, how do I find out what was there originally?
Try to read up as much as you can on your house and it's history.
Look for bumps or old fixing holes in your plaster work.
Look at other houses of similar age and style in your area to see whether they have any original mouldings.
How should I paint my dado rail?
Historically, during the early 18th century, the panelled walls, along with the dado rail, were often painted in one colour.
I'm a big fan of using the same colour on the whole wall, all the way from the skirting board to the cornice. When you paint everything, the skirting, the dado and picture rails in the same colour, it makes the room appear bigger and creates a calm, elegant atmosphere.
According to Patrick Baty in his book The Anatomy of Colour "...the relative complexity of the panelled wall surface was not an excuse for the elaborate 'picking out' beloved by so many modern interior designers." You can follow Patrick on Instagram @theanatomyofcolour.