Should I Use 2X4 or 2X6 For Shed Exterior Walls?

Recently I was talking with a friend about what size of lumber to use when framing a shed. When I framed my shed, I never considered using anything beyond 2×4 lumber for the exterior walls. However, my friend mentioned that he used 2×6 wall framing not just for his shed but also for his garage.

Using 2×4 lumber for shed exterior walls is more than adequate for a standard, single-story shed. Exterior shed walls using 2×6 lumber are more suited to sheds with walls higher than 8’, or sheds that will double as living space. The wider lumber allows you to install more insulation and also place the studs further apart.

Since you can spread your 2×6 studs further apart – 24” on center – it reduces the amount of lumber you’ll need compared to 2×4 16” on center walls. The total cost of a shed with 2×4 walls is similar to that of a 2×6 shed.

In this article, we’ll go over all the pros and cons of using 2×4 versus 2×6 lumber for your exterior shed walls. Plus, we’ll also go over interior walls and how to determine if your shed should have 2×6 or 2×4 exterior walls.

How Thick Should Exterior Walls Be?

This depends on how you intend to use your shed. The minimum sized lumber for a shed exterior wall is 2×4. Since 2×4 lumber is 1.5” x 3.5”, your walls aren’t as thick as you’d think.

However, we know that your shed walls will be more than just studs. The sheathing is anywhere from ⅝” to ⅜” thick. Siding can range from ½” to 1” thick. Therefore, you are looking at a minimum of 5” of thickness. And that’s not counting any type of drywall or interior sheathing.

There is not a maximum in terms of exterior shed wall thickness. But when planning your shed wall design, you must account for the shed size and space it will occupy. If your backyard can support a maximum shed size of 8×8, then you will want to minimize the thickness of your walls to maximize the relatively small square footage of an 8×8 shed.

Insulation is also a factor when calculating whether you will use 2×4 or 2×6 wall framing. If you plan on adding foam panels outside your sheathing for extra insulation, then you are looking at a wall of around 8” thick for a wall using 2×6 lumber. On the other hand, if you use batts to insulate, you can fit more insulation between 2×6 lumber.

Your exterior walls should be thick, using 2×6 lumber, if you are going to spend lots of time in the shed. That will allow you significant insulation and maximize the efficiency of whichever heating or cooling source you choose to use.

If your geography doesn’t experience huge swings in temperature, and you are not going to make a loft or second story on your shed, then less thick walls using 2×4 framing is perfectly acceptable.

Should Exterior Walls Be 2×4 or 2×6?

Your shed can have either 2×4 or 2×6 walls – it depends on your preference, what you intend to use your shed for, and the dimensions of the entire structure.

The ultimate consideration of whether to use 2×4 or 2×6 shed wall framing is what you actually want to use your shed for, whether it is a tiny house, workshop, or just a simple storage area.

If space isn’t an issue because you have a huge backyard, then you could use 2×6 lumber.

However, if you are building a storage space and do not intend to spend time in the shed, there is not much benefit to using 2×6 framing. Why? It will cost you more, provide a negligible structural benefit, and take up more interior space than 2×4 framing. As well, 2×6 lumber is not significantly more expensive than 2x4s.

The only time it makes sense to use 2×6 lumber is if you plan to use your shed as a work or living space. 2×6 framing gives you more options for insulating, and it also provides a better foundation for creating a loft space above.

Let’s take an 8×8 shed built with 2×6 lumber as an example. A 2×6 is actually 5 ½” thick. Add another ½” of sheathing and ½” for siding. Now you’ve got over half a foot per side of your shed devoted to wall framing. Multiply by 2 and you have 13” of interior space gone thanks to your use of 2×6 lumber. Alternatively, you’d only sacrifice 9” of interior space using 2x4s.

But what if you want to use your shed as a liveable space or a workshop? 2x6s might be a better option, and here’s why: you can insulate a space more efficiently and more cheaply than you can with 2x4s.

Insulated 2×6 shed walls would use R-22 batts. To achieve the same results with 2×4 framing, you would need to add 1 ½” of foam insulation on the outside of the shed walls to achieve a similar R-value. With the added foam, the 2×4 framing would be the same thickness as the 2×6 framing without the foam.

Additionally, the added cost of foam insulating panels would offset any savings you’d gain by using 2x4s and the corresponding batts that would fit with 2×4 framing.

Therefore, you don’t gain any floor space with 2×4 wall framing that is insulated to equal 2×6 framing. Plus, when you use 2×6 framing, you can frame your walls over 8’. This will allow you to have an extra high ceiling or build a loft in your shed. Walls over 8’ require 2×6 lumber. Also, if your shed is wider than 16’, then you’ll also want to use 2×6 wall framing.

Another factor to consider is how your windows and doors will fit into your shed wall framing. Doors and windows are designed to fit into 2×4 framing. If you do opt for 2×6 framing and want the interior of your shed to be a nice, liveable, finished space, then you’ll need to special order your doors and windows to fit 2×6 framing, which will cost you more.

Remember that a simple storage shed does not need 2×6 construction. A properly constructed 2×4 shed will withstand any snow load or wind storm. Consider 2×6 construction only when outfitting your shed for a specific purpose other than storage.

2×4 vs. 2×6 Strength

People often use 2×6 framing because they are stronger. However, since 2×6’s are spaced further apart – 24” on center – it negates their strength value as compared to 2×4 16” o.c. wall framing. The improved strength only works if you space the 2×6 lumber at 16”, just as you would 2×4 walls.

2×6’s are better for areas that sustain high winds or storms, as they can withstand bending for better than a 2×4. As mentioned above, heavy snow loads can easily be handled by appropriately constructed 2×4 framed sheds.

Can you Use 2×6 Insulation in 2×4 Shed Walls?

No. You cannot compress batts. Fiberglass and Stone Wool insulation utilize millions of tiny air pockets to minimize conductive heat transfer – which is the transfer of heat between solid objects.

If the air pockets are compressed, such as when you put an R-22 batt into a 2×4 wall cavity meant for R-13, then you’ve essentially negated the insulating capabilities of the entire batt.

Better to use foam along the outside of the 2×4 sheathing to achieve the same R-value as a 2×6 framed shed wall. The other benefit of exterior rigid foam insulation is that it breaks the thermal barrier between the studs and sheathing. The downside, of course, is that rigid exterior foam is an added cost – up to $25 for a 4×8 R-5 piece.

Naturally, the more insulation you use, the better efficiency you’ll achieve within your workspace or tiny house. However, the cumulative energy savings between different types of insulation over the course of a year in a space that isn’t a primary dwelling will be negligible.

Therefore, your primary consideration should always be accounting for interior space and structural stability. Since insulation can always be applied to the exterior via rigid panels, the question of using 2×6 vs. 2×4 framing in shed walls should, thus, not hinge on insulation.

Interior Shed Wall Thickness

If you opt to have interior walls in your shed, then you do not need to use 2x4s as these walls will not be load-bearing.

A better option is 2x3s. These are often finger-jointed pieces of lumber that are more than adequate to hold up an interior wall. It also means they are cheaper than a 2×4 and quick to erect.

A 2×3 will hold drywall or other interior finishes easily. These are a common interior framing lumber for non-load bearing walls in basements, garages, and other structures where loads are not a factor.

It is also possible to use 2×2 lumber to frame an interior shed wall that is not load-bearing. While this might seem too narrow, many old houses throughout North America used this dimension of lumber for non-load bearing walls.

Just understand that if you choose to use 2×2 walls, you’ll need a conduit to run wires within those walls and use care when joining the members. ⅜” drywall is an acceptable weight to put on these walls, but don’t go any thicker as a 2×2 wall can only hold so much weight.

Is 2×6 Construction Better Than 2×4?

Yes. Two exterior walls constructed with 2×6 and 2×4 respectively, without any added foam or other insulation around the outside, show that 2×6 is superior to 2×4 exterior walls.

Strength

While dead load strength between the 2×4 and 2×6 framing is virtually the same when 2×4’s are framed at 16” o.c. and 2×6’s are framed at 24” o.c., the values vary much more widely when considering the wind.

A 2×6 wall is not nearly as prone to bending or twisting – such as during a wind storm – compared to 2×4’s. The width of a vertical 2×6 is too much for a high wind to cause any type of structural change.

2×6 shed wall framing is stronger than 2×4 framing, particularly with walls greater than 8’, supporting a loft or another level, and during high winds.

Insulation

Without any rigid exterior foam, the 2×6 shed wall can hold more insulation than a 2×4 wall. Adding rigid insulation adds cost and time to a project. Therefore the 2×6 framed wall for a shed is superior. The added cost for the 2×6 lumber and larger batts is negligible considering the reduced heating and cooling costs you’ll achieve with the larger lumber.

A 2×6 wall cavity can hold a higher R-value of insulation, making it more practical for work or liveable space.

Cost

The overall cost of using 2×6 lumber vs traditional 2×4 studs is more – roughly $3 more, on average for an 8’ length. However, keep in mind that you’ll need fewer since you’ll be framing at 24” o.c.

Using an 8×8 shed as an example, you would need 7 2×4’s per side if using 2x4s. But you would only need 5 per side if using 2x6s. If a 2×4 costs $5, then you’d spend $35 per wall using 2x4s and $40 per wall using 2x6s.

In total, you’d be spending an extra $20. While that is a smaller shed design, you can extrapolate that data and conclude that the extra cost for a larger shed would still be minimal. For that reason, opting for the 2×6 wall construction makes fiscal sense.

2×6 wall framing allows for larger gaps between studs, which keeps the cost of using 2×6 lumber in line with using 2×4 lumber.

Installation

The construction of 2×6 shed walls is no different than using 2x4s. In fact, constructing a wall of 2x6s for a shed is likely faster since you’ll be using fewer pieces of lumber.

One consideration, however, is that if you are constructing a larger shed using 2x6s, you’ll likely need a hand erecting a wall as the weight of the 2x6s can quickly become a burden if attempting to lift the wall on your own.

There is no difference when installing 2×6 framing vs. 2×4 framing, and using the 2×6 lumber for framing may be even faster.

Conclusion

Remember that any consideration of different types of lumber for wall framing should first consider the space it will be occupying. A thoroughly detailed plan of not only the shed but also space in the yard where the shed will live is critical.

Once you’ve assessed the area where the shed will go, then you’ll need to consider the function of your shed. These two factors will then influence what type of shed wall framing you’ll use.

No matter which type of lumber you use, the proper use of either will result in a perfectly stable and sound shed that you’ll be able to use for years, if not decades. Just be sure to abide by local building codes and pull all necessary building permits.

Once again, I hope you’ve enjoyed this article. Thanks for taking the time to read it and please drop me a line if you have any suggestions or feedback regarding the framing of shed walls.