Padstone

A padstone is a block made from stone or concrete that is used to distribute a point load evenly into a structure. In modern building, they are typically installed to distribute the load evenly at points where the ends of beams and lintels are built into a wall. They therefore relieve a concentrated load, so the risk of crushing or cracking the material below the padstone is reduced.

In modern masonry, a wall made from concrete blocks may have padstones made from a more dense concrete block to withstand point loads; without this, the standard blocks could crack causing structural damage. Dense blocks used as padstones are typically manufactured to have compressive strengths in the region of 40N/mm2. An alternative in the same construction is to use a few courses of dense clay bricks immediately below the beam ends.

In traditional timber-framed construction, foundations in the modern sense would not usually be provided. For a cruck-framed building, the point loads from the cruck feet or posts would be transferred into padstones and eventually to the bearing layer of soil.

The concept of this early type of foundation continues today: pad foundations are used to transfer point loads into the soil and are usually placed at shallow depths. They may be square, rectangular or circular, and may even be stepped if subjected to heavy loading from the superstructure. They can be made from plain or reinforced concrete. See pad foundations for more information.

[edit] Related articles on Designing Buildings Wiki

• Architectural styles.
• Building component.
• Building element.
• Building design.
• Building regulations.
• Building technology.
• Building works.
• Construction works.
• Pad foundations.
• Housing stock / building stock.
• Structure definition.
• Timber frame.
• Types of building.
• Wall types.