Some of the terms used in the preceding guide to building raised beds may confuse you. Fear not for this brief article will help.
What follows is a list of some common terms, tips, tools and techniques to help you build raised beds. They also apply to many other home carpentry projects.
Use what you need. If you still have questions, ask a professional.
|This bed uses 2-by fir attached to 4x4 posts with lag screws.|
Four types of wood are often used in raised beds: redwood, pressure treated fir (or other wood), untreated fir and untreated pine. Each has its advantages and disadvantages.
Redwood can withstand direct contact with the soil and last at least 10-20 years. However, it often costs about three times more than untreated pine or fir.
Untreated pine or fir generally lasts 5-10 years, longer if sealed with a clear coat. This tends to be the least expensive material because it is frequently used in home construction.
|Year-old planters are made with redwood. Pressure treated|
wood is used to line a walking path, not in planting beds.
Wood sizes are often misleading to novices. When someone talks about a “2 by 4,” they are talking about a piece of wood in its raw, untreated size. Milling reduces these dimensions by about 25 percent, making a 2 by 4 actually 1.5 inches thick by 3.5 inches wide.
Be wary of warps and crowns. Warps will cause the wood to bow in or out. Crowns will cause it to bow up or down at one end. You can correct for a slight warp by using screws. Crowns are harder to fix.
Saws and Cutting
Wood needs to be cut to make your raised beds. Some stores and lumber yards will cut your wood at no charge. Others charge a nominal fee. If you are uncomfortable working with power saws, have the pros do it but be sure to carefully measure what you need first.
If you are going to cut the wood yourself, consider buying what’s commonly known as a Skil ® saw with a blade 5 inches or greater in diameter. These saws give you a lot of flexibility but require a steady hand and care when using.
When attaching your wood, also try to use at least one end with a square cut. This is a cut with a perfect 90-degree angle, like what you will get from a lumber yard. Some homeowners' do not cut perfectly straight, which can throw their beds off when assembled. Using square cuts on at least one edge results in a better bed.
Drills and Screwdrivers
Your typical small cordless screwdriver does not have enough power for this type of task. Either get an 18-volt or greater cordless model or a fairly powerful corded electric drill.
Since assembling the sides of your raised beds involves pre-drilling holes then inserting screws, you might find it efficient to have two drills and load one with a drill bit slightly shorter and narrower than your screws. Use the second drill for driving in the screws.
Measuring and Leveling
One of the most frequently used tools in any carpenter’s kit is a carpenter’s square. This simple device has a 12-inch metal ruler, a simple bubble and a 45-degree stop. Use this for drawing cutting lines and for perfectly positioning drill holes on wood up to
Larger squares (they look like a large metallic “L”) are better when working with bigger pieces of wood such as sheets of plywood.
Bubble levels come in a variety of lengths. A 2-3-foot bubble level is sufficient for most home construction projects. Longer levels, such as 6-footers, are only needed for major construction projects.
Screws and Hardware
You can attach the sides of your raised bed to your posts using nails, screws or lag screws.
A personal preference is avoiding the use of nails because too much force can split boards, costing you money and time.
Your typical Phillips head wood screws work just fine most of the time, provided you make sure they are wider and longer than the drill bit used to pre-drill their holes. Consider using regular screws when building raised beds with “one by” wooden sides.
Lag screws are larger and far heavier than normal screws. You will need a socket wrench to drive them. Personal preference is using lags when working with “two by” thick wood and 4-by-4-inch posts because lags have the strength to handle the additional weight.
If are going to use lag screws, pre-drill a 1-inch diameter (or smaller) hole about a half-inch deep in your side board, then pre-drill your screw hole. The larger diameter hole adds depth to screw hole and keeps the screw head flush with the outer edge of your board.
You can also use brackets but they can add a substantial cost to your project.
Power tools are not forgiving. The slightest amount of inattention can cost you a finger or worse. Splinters can fly up and destroy an eye. Boards can bounce back and clobber you. Loud noises, such as saws, can damage your hearing.
For those reasons, it’s always a good idea to wear gloves, clear plastic eye protectors and either foam earplugs or slip-on hearing protectors. Keeping a solid grip and even pressure on wood being cut will eliminate the bounce backs.
There Is No Substitute for Experience
Building raised beds is a simple project for anyone, even novices. However, pros know what to and how to do it so they are much faster and more accurate. When in doubt, talk to people and hire a pro.