The minimum tread size is commonly stated as 9 inches for residential construction.
Minimum stair tread size.
According to building codes stair tread for wood stairs has to be anywhere from 1 to 1 in thickness.
Stair tread depths shall be 11 inches 279 mm minimum.
Minimum 10 inch stair tread depth with nosing or minimum 11 inches with no nosing.
Buildings codes have been created to control the minimum and maximum measurements of risers and treads.
As general rules of thumb for achieving comfortable relationships between riser and tread dimensions the following formulas can be used.
The stair tread depth shall be measured horizontally between the vertical planes of the foremost projection of adjacent treads and at right angle to the tread s leading edge.
Handrail graspability to be either type i or ii with a minimum 1 1 2 inch clearance from a wall.
There isn t one unifying rule for every kind of material stair treads may be built out of.
The stair tread depth shall be measured horizontally between the vertical planes of the foremost projection of adjacent treads and at right angle to the tread s leading edge.
The greatest depth at the 12 inch mark must not exceed the smallest on any other tread by more than 0 375 inches.
However the americans with disabilities act ada lists the minimum tread size as 11 inches which would be the effective minimum and likely the average size of the tread for any stairs built for public use.
However if the steps do not have nosings and the steps have solid risers not open risers the minimum tread depth is 11 inches.
This distance must be at least 10 inches.
This narrow side must have a minimum tread depth of 10 inches.
Tread inches 2x riser inches 24 25 26 for exterior stairs riser inches x tread inches 72 75.
The minimum general tread depth remains 11 inches but it is measured at a right angle from the leading tread edge that is 12 inches from the narrowest side.
When it comes to other materials the thickness may differ.
Staircase risers should be adequately deep to allow a majority of your foot to have enough room to rest on the stair.
This is because stair treads can be crafted from thick oak to think stainless steel.
Stair tread depths shall be 11 inches 279 mm minimum.