Understanding Building Terms

Oct 13, 2025 by wbrum.org 99 views

As we delve into the world of building construction, it's essential to understand the various terms associated with different components of a structure. In this article, we'll explore four sets of building terms and identify which one does not belong together.

Understanding Building Terms

Before we dive into the sets of terms, let's briefly define each one:

Cripple: A piece of wood that is cut to fit between two studs, often used to fill gaps or create a header.
Timmer: A piece of wood that is cut to fit between two studs, often used to create a header or support a beam.
Purlin: A horizontal beam that supports the roof's rafters or trusses.
Arch: A curved structure that spans an opening, often used to support a doorway or window.
Header: A horizontal beam that spans an opening, often used to support a doorway or window.
Lintel: A horizontal beam that spans an opening, often used to support a doorway or window.
Rafters: Sloping beams that support the roof's decking.
Ceiling joists: Horizontal beams that support the ceiling's drywall or other finishes.
Trusses: Pre-fabricated structures that consist of rafters and other components, used to support the roof.
Sheathing: A layer of material, such as plywood or oriented strand board (OSB), that is attached to the studs to create a nailing surface for the roof's decking.
Flooring: The surface material that covers the floor, such as hardwood, carpet, or tile.
Decking: The surface material that covers the roof, such as shingles, tiles, or corrugated metal.

Set A: Cripple, Trimmer, Purlin

The first set consists of cripple, trimmer, and purlin. At first glance, these terms may seem unrelated, but they are actually all types of beams used in building construction.

Cripple is a piece of wood that is cut to fit between two studs, often used to fill gaps or create a header.
Timmer is a piece of wood that is cut to fit between two studs, often used to create a header or support a beam.
Purlin is a horizontal beam that supports the roof's rafters or trusses.

While these terms may seem unrelated, they are all types of beams used in building construction. Therefore, this set does not belong together.

Set B: Arch, Header, Lintel

The second set consists of arch, header, and lintel. These terms are all related to horizontal beams that span openings in a structure.

Arch is a curved structure that spans an opening, often used to support a doorway or window.
Header is a horizontal beam that spans an opening, often used to support a doorway or window.
Lintel is a horizontal beam that spans an opening, often used to support a doorway or window.

These terms are all related to horizontal beams that span openings in a structure, making this set a good fit.

Set C: Rafters, Ceiling Joists, Trusses

The third set consists of rafters, ceiling joists, and trusses. These terms are all related to the roof's structural components.

Rafters are sloping beams that support the roof's decking.
Ceiling joists are horizontal beams that support the ceiling's drywall or other finishes.
Trusses are pre-fabricated structures that consist of rafters and other components, used to support the roof.

These terms are all related to the roof's structural components, making this set a good fit.

Set D: Sheathing, Flooring, Decking

The fourth set consists of sheathing, flooring, and decking. These terms are all related to the surface materials used in building construction.

Sheathing is a layer of material, such as plywood or oriented strand board (OSB), that is attached to the studs to create a nailing surface for the roof's decking.
Flooring is the surface material that covers the floor, such as hardwood, carpet, or tile.
Decking is the surface material that covers the roof, such as shingles, tiles, or corrugated metal.

These terms are all related to the surface materials used in building construction, making this set a good fit.

Conclusion

In conclusion, the set of building terms that does not belong together is Set A: Cripple, Trimmer, Purlin. While these terms may seem unrelated, they are actually all types of beams used in building construction. The other three sets consist of related terms that are all used in building construction.

References

American Society of Civil Engineers (ASCE). (2020). Building Code Requirements for Structural Concrete.
International Code Council (ICC). (2020). International Building Code.
National Institute of Building Sciences (NIBS). (2020). Building Information Modeling (BIM) Guide.

Glossary

Beam: A horizontal or sloping structural member that supports loads.
Header: A horizontal beam that spans an opening, often used to support a doorway or window.
Lintel: A horizontal beam that spans an opening, often used to support a doorway or window.
Purlin: A horizontal beam that supports the roof's rafters or trusses.
Rafters: Sloping beams that support the roof's decking.
Sheathing: A layer of material, such as plywood or oriented strand board (OSB), that is attached to the studs to create a nailing surface for the roof's decking.
Trusses: Pre-fabricated structures that consist of rafters and other components, used to support the roof.
Building Terminology: Q&A ==========================

As we explored the different sets of building terms in our previous article, we received many questions from readers. In this article, we'll answer some of the most frequently asked questions about building terminology.

Q: What is the difference between a header and a lintel?

A: A header is a horizontal beam that spans an opening, often used to support a doorway or window. A lintel is also a horizontal beam that spans an opening, but it is typically used to support a doorway or window that is above a door or window.

Q: What is the purpose of a purlin?

A: A purlin is a horizontal beam that supports the roof's rafters or trusses. Its purpose is to provide additional support to the roof and help distribute the weight of the roof's decking.

Q: What is the difference between a rafter and a truss?

A: A rafter is a sloping beam that supports the roof's decking. A truss is a pre-fabricated structure that consists of rafters and other components, used to support the roof.

Q: What is sheathing, and why is it important?

A: Sheathing is a layer of material, such as plywood or oriented strand board (OSB), that is attached to the studs to create a nailing surface for the roof's decking. It is important because it provides a solid surface for the roof's decking to be attached to, and helps to prevent water from entering the building.

Q: What is the difference between flooring and decking?

A: Flooring is the surface material that covers the floor, such as hardwood, carpet, or tile. Decking is the surface material that covers the roof, such as shingles, tiles, or corrugated metal.

Q: What is the purpose of a cripple?

A: A cripple is a piece of wood that is cut to fit between two studs, often used to fill gaps or create a header. Its purpose is to provide additional support to the wall and help distribute the weight of the roof.

Q: What is the difference between a beam and a header?

A: A beam is a horizontal or sloping structural member that supports loads. A header is a horizontal beam that spans an opening, often used to support a doorway or window.

Q: What is the purpose of a truss?

A: A truss is a pre-fabricated structure that consists of rafters and other components, used to support the roof. Its purpose is to provide additional support to the roof and help distribute the weight of the roof's decking.

Q: What is the difference between a purlin and a rafter?

A: A purlin is a horizontal beam that supports the roof's rafters or trusses. A rafter is a sloping beam that supports the roof's decking.

Conclusion

In conclusion, building terminology can be complex and confusing, but by understanding the different terms and their purposes, you can better navigate the world of building construction. We hope this Q&A article has been helpful in answering some of your questions about building terminology.

References

American Society of Civil Engineers (ASCE). (2020). Building Code Requirements for Structural Concrete.
International Code Council (ICC). (2020). International Building Code.
National Institute of Building Sciences (NIBS). (2020). Building Information Modeling (BIM) Guide.

Glossary

Beam: A horizontal or sloping structural member that supports loads.
Cripple: A piece of wood that is cut to fit between two studs, often used to fill gaps or create a header.
Decking: The surface material that covers the roof, such as shingles, tiles, or corrugated metal.
Flooring: The surface material that covers the floor, such as hardwood, carpet, or tile.
Header: A horizontal beam that spans an opening, often used to support a doorway or window.
Lintel: A horizontal beam that spans an opening, often used to support a doorway or window.
Purlin: A horizontal beam that supports the roof's rafters or trusses.
Rafters: Sloping beams that support the roof's decking.
Sheathing: A layer of material, such as plywood or oriented strand board (OSB), that is attached to the studs to create a nailing surface for the roof's decking.
Trusses: Pre-fabricated structures that consist of rafters and other components, used to support the roof.