When I was first getting into home improvement and DIY stuff, it felt like every resource I found used a bunch of terms that I didn’t know. Few of these are, in and of themselves, particularly technical or complicated ideas. It is just lingo that people in the construction trades use. I thought it would be helpful to compile a glossary of these terms. This is hardly an exhaustive list. I’ve tried to include terms that I think are likely to be encountered by the average person trying to take on projects around the house.
Working With Lumber
- Rip Cut: Cutting a piece of lumber with the grain. These are often longer cuts and fence or guide is needed to deliver an accurate result
- Cross Cut: Cutting a piece of lumber against the grain. These are typically shorter cuts and can be done free hand with a circular saw, for example, although a miter saw or table saw with a cross cut sled will provide more accuracy.
- Round Over: Finish an edge with a rounded profile, often done by a router with a round over bit.
- Movement and dimensional stability: Wood is a natural product and will expand and contract seasonally based on ambient humidity. Softwoods will move more than hardwoods and engineered woods like plywood and MDF move so little that you don’t need to factor movement in to a design or installation. There is much to be written about wood movement.
Wood Joints
- Butt:
- Miter:
- Scarf:
- Lap:
- Rabbet:
- Dado:
Types of Lumber
- Trim: Trim can take many different forms but is usually thinner stock than structural lumber. It is also typically appearance grade, meaning fewer knots and other blemishes. 3/4 inch flat stock trim is common and can be often be bought in 1×4 or 1×6 dimensions. Pine is a commonly used wood, although poplar is also often available at home improvement stores. Both are most often used for paint grade finishes. PVC is often used for exterior trim. Trim is also commonly available in MDF or finger-jointed.
- MDF: Medium Density Fiberboard
- Finger-joint: Boards, often made from multiple distinct pieces of pine, that have been joined together by gluing edges cut with a “finger-like” profile together. This is going to be less expensive to purchase than a solid wood board and will lack the structural characteristics of solid wood, but is fine for trim applications.
- Plywood: Usually purchased in 4’x8′ sheets, plywood can be purchased in a variety of thicknesses for many different applications. Plywood is an engineered product and is very strong and dimensionally stable.
- Dimensional Lumber: When someone says 2×4 or 1×6 what they are referring to is dimensional lumber. There are about a dozen or so sizes of dimensional lumber that are regularly used in construction projects, often in framing applications, and typically softwood (pine, fir, cedar, etc). The first number refers to the thickness and the second number refers to the width, so a 2×4 is 2 inches thick and 4 inches wide. These are nominal dimensions though. a 2×4 is actually 1.5″ thick by 3.5″ wide. Dimensional lumber is commonly sold in 8, 12 and 16 foot lengths.
- 5/4 Inch Decking: Most decking is sold as 5/4, which is actually one inch thick, with a rounded profile.
- Pressure Treated Lumber: Most PT lumber is Southern Yellow Pine that has been injected with a chemical treatment that makes the lumber resistant to rot. For exterior use. There are few woods that are naturally resistant to the abuses of exterior use. In the US, cedar (just the heartwood), cypress, osage orange, and black locust are examples of woods that are appropriate for exterior use. Several tropical woods, like Ipe, will last for decades outside, but there are lots of environmental problems associated with tropical hardwoods. While there are some debates about the toxins used in pressure treating, PT lumber is the most commonly used lumber in exterior applications.
- Hardwood: Almost all wood that is classified as “hardwood” comes from deciduous trees. Softwoods are generally coniferous (or evergreen). Hardwoods are not likely to be sold as dimensional lumber, although home improvement stores often stock a limited selection of hardwood boards in a 1×6 dimension. Most woodworkers purchase rough sawn hardwoods from a sawmill or hardwood lumber yard by the board foot. Hardwoods are much more expensive than softwoods and purchasing lumber by the board foot is the most economical way to buy.
Moldings and Trim Profiles
- Crown molding
- Classical moldings
- Plinths
- Astragals
- Casements
Measuring
- Proud
- Flush
- Square
- Plumb
Fasteners
- Brads:
- Screws vs Nails:
- Drywall Screws:
Lumber
- Rip cut
- Cross cut
- Trim
- Round over
- Plywood
- Dimensional lumber
Measuring
- Proud
- Flush
- Square
- Plumb
Fasteners
- Brads