5 Best Types of Wood to Build Outdoor Signs

If you are building a wooden sign that will be displayed outdoors, the first thing you need to do is decide which type of wood to use. Different types of wood are best suited to different applications and some are not great for outdoor signs.

This article will explain why it is important to choose the right type of wood and give you some examples of the best woods for outdoor signs. It will also give some great information about creating and weatherproofing your signs too. So, read on to find out the best types of wood to build outdoor signs.

Does the Wood Type Matter for an Outdoor Sign?

Yes, there are a few key reasons why you need to pick the right wood for your outdoor sign. The first is durability. Some types of wood hold up well when exposed to the elements, like Cedar and Redwood, for example. Others will take on a lot of moisture and rot, or they will dry out and crack in the sun. 

You also need to consider how you are going to get your design onto the sign. If you are painting it on, you need something that takes paint well. However, you may be carving into the wood, in which case, you need softwood.

Finally, think about the aesthetic you want. If you plan to go for a rustic sign and keep the natural wood, you need something with a nice grain. On the other hand, you could paint or stain the sign to change the color.

Although durability is probably the most important thing, you need to consider all of these factors when deciding which wood to use for your outdoor sign.

5 Best Woods for Outdoor Signs

Here are my top picks for wood for outdoor signs. The best choice for you depends on your specific needs but these are all solid options.

1. Medium Density Overlay (MDO)

three light plywood boards stacked on top of each other

Medium Density Overlay, or MDO, is probably the best choice if you want something hard wearing that will stand the test of time. It is plywood that has been heat and pressure treated with a weatherproof resin. You won’t be able to use this for carving a nice rustic wooden sign, but if you want a painted sign, this is ideal. It takes paint nicely and the wood itself will easily stand up to the elements.

When painting an MDO sign, check whether it has been primed or not. Some have already, but most of the time, you will need to apply a coat of primer first. Don’t skip this step because it will take a lot longer to get a nice finish if you apply paint straight onto the surface.

You can expect an MDO sign to last at least a decade without much maintenance at all. If you apply a sealer on a semi-regular basis, it will last indefinitely.

2. Redwood

MDO is a good choice if you are purely interested in longevity, but if you want a natural wood sign on the outside of your home, for example, it’s not the best choice. Redwood is a close second on the list because it’s incredibly durable and it looks great. It has a lovely rich color that is great for carved or painted signs. Redwood has a high oil content too, which makes it naturally moisture-resistant. Technically, you can use it outside with treating or sealing it at all and it will last a good few years. However, if you want to get the most out of it, there’s no harm in treating the wood.

3. Cedar

cedar boards great for a sign

Cedar is another very durable wood with a high oil content for natural moisture resistance. It has a lighter color than redwood but can easily be stained or painted if you like. Cedar is a softwood, making it easy to carve too.

Both redwood and cedar are excellent choices because they are naturally resistant to moisture. The only potential downside is that they can be more expensive than other types of wood.

4. Cherry Wood

Cherry is a great hardwood that looks beautiful and works brilliantly for exterior signs. It’s hard-wearing and has a very close grain, which means that it is not prone to shrinking or warping. This is a big bonus if you live somewhere with a varied climate because exposure to moisture and rapid temperature changes can often lead to cracking.

The other great thing about cherry is the way that it weathers in the sun. Many types of wood will lose their color and turn a dull gray after prolonged exposure to UV rays but cherry turns a deep shade of red and actually looks better with age.

5. Douglas Fir

Stacked untreated Douglas fir,

Finally, you have douglas fir. This is the most common type of softwood in the US, so it’s a more affordable option, especially for carved signs. It has a nice reddish brown color, sometimes more orange depending on the tree it comes from. It has a very high strength compared with other wood, as well as a natural moisture resistance. It may not be the most durable wood species in the world, but when you consider the relative price, it’s perfect for your outdoor signs. 

What Signs Can You Make Using These Types of Wood? 

These are all great types of wood for making exterior signs. They can be used for all manner of signs including: 

  • Business Sign
  • Home Welcome Sign
  • House Number Sign
  • Neighborhood Signs 
  • City and Town Signs
  • Road Signs
  • Garden Signs
  • Real Estate
  • Campground Signs
  • Forest/Nature Walk Signs
  • Open and Closed Signs for Retail
  • Farm Signs
  • Golf Course Signs
  • Map/Direction Signs
  • Wedding Signs
  • Health and Safety Signs
  • Any other sign you can think of!

What Type of Wood is Best for Carving Outdoor Signs?

If you want to carve an outdoor wood sign, you will usually use softwood. As discussed above, redwood and cedar are both excellent softwood varieties that you can carve into. Other great softwoods include pine and douglas fir.

However, you don’t always need to use softwood. Some of the softer varieties of hardwood, like Poplar, are also excellent for signs. Although they are not considered high quality woods, things like MDF and plywood can be carved if you want. They will need to be painted if you want a good finish, but they’re a cheap option.

Overall, I would go for something like redwood or cedar, or if you want a more affordable option, pine is great.

Are There Any Types of Wood to Avoid Using?

Moisture is your biggest problem when using wood outside, that’s why you should look for species that have a high oil content, giving them natural resistance to moisture. But even though some wood is better than others, all wood is technically suitable for use outdoors, it just depends on the level of maintenance. Wood that has less natural moisture resistance will require more protection and regular sealing, but even the most durable wood will eventually rot and so it will need sealing.

If I had to pick woods that should be avoided, I would say things like Ash, Birch, Beech, and Spruce, which all score very low on the durability scale, so won’t last more than a year or so outside without a lot of maintenance.

What are Some Wood Substitutes for an Outdoor Sign? 

If you don’t want to use wood for whatever reason, there are plenty of alternatives:

  • Metal 
  • Vinyl
  • Polyester
  • High-density urethane (HDU) foam
  • Dibond (plastic core with an aluminum exterior)
  • Composite wood products

In most cases, these other materials will withstand the weather better than wood. However, you won’t get the same authentic look that you would with real wood. Also, many of them are less eco-friendly, especially things like polyester and vinyl.

How Can You Make an Outdoor Sign Weatherproof? 

No matter what kind of wood you use, you should treat it to make it weatherproof. This will drastically increase its lifespan so you don’t need to replace the sign for years to come. Wood oil is a good option if you are using a nice wood like cedar or cherry and you want to bring out the natural grain. It also offers protection from moisture, but it needs to be reapplied more often than other options, like a clear coat. 

Clear coats are excellent because, not only do they create a seal against moisture, but many of them also protect against UV. If you are using a type of wood that goes gray in the sun, a clear coat is the way to go. Check out our excellent guide on the best clear coats for outdoor wood for more info. 

Can You Paint an Outdoor Wood Sign? 

Absolutely! You might decide that you want a painted sign when building a new one, or you could paint an old sign to bring it back to life. Painting not only gives you some fresh color but it also protects the wood against moisture, as long as you use the right paint.

What Type of Paint Should You Use on Outdoor Wood Signs?

When you are choosing paint for your sign, you must make sure that you are using a product that is specifically designed for exterior use. If you use interior paint, it will wash off the first time it rains and you’ll be left with a big mess. As a general rule, oil paints are the way to go when painting exterior wood because they’re tougher and they give a nice finish. That said, if you want something that dries faster and is easier to clean up, there are some good water-based options on the market. If you are planning to paint your outdoor wood sign, you can find a full guide to help you choose the right paint here.