How Far Can a Deck Overhang a Joist (Everything You Need to Know)

There is no denying that decking is incredibly aesthetically pleasing, and a big part of this is because of the overhang. You do not need to have an overhang on your deck, but if you do not, it can make your deck look dense and bulky. Whereas, if you have an overhang, it can make your deck look a lot more attractive, as well as making it appear more spacious and luxurious. But when does an overhang become unsafe? 

If you are designing your deck yourself, and you do not have professional experience in this, then you might not have the necessary knowledge regarding this. That is why we have put together this handy guide. So, if you want to find out everything you need to know about overhang for decking, then keep on reading. 

Can Decking Overhang Joists?

Yes, as you probably already know, your decking boards can overhang the joists that support your decking. As we have said, this overhang is what makes up a large part of the decking aesthetic, so it is likely that you will want an overhang if you are designing your deck yourself. 

But, it is very important that you take care when designing this, and do the proper research to find out how much of an overhang is safe for your decking. Like we have said, it is perfectly fine to have an overhang, but it is important that you follow rules and regulations to ensure that your decking is safe. 

If you are having a professional joiner design and build your decking, then the amount of overhang that you are allowed will be less important. This is because the joiner will have a lot of experience in designing and building decks, and because of this they will know the rules and regulations for decks. So, your knowledge will become less important, as the joiner will not build a deck that is unsafe. 

However, generally speaking, it is a good idea to get a general understanding of the rules and regulations of decking before you invest in one. 

How far should Decking Overhang?

If you are in the process of installing a deck, then you might be wondering just how far your decking should overhang. Like we have said, if you are having a professional do the job, then they will be able to give you advice on what the ideal overhang is for the style of decking that you are having installed. But, if you are taking on this task yourself, then it can be a little more difficult to find out exactly how far your decking should overhang. 

There are lots of different things that impact the ideal overhang for decking. We will take a further look at these later on, but they mainly concern the type of wood used, and the size of the joists that you are building upon. As there are so many factors that impact the exact amount of overhang that is suitable for decking, it is vitally important that you do research to calculate how much of an overhang is suitable for your deck. 

This is the main reason why so many people choose to have a professional in to do the necessary work on their decking. There is a lot of planning that goes into building a deck that you might not have previously considered. But, if you have a professional to do the job, then they can do the majority of the planning work for you. 

What Impacts Overhang on Decking?

As we have said, there are lots of different things that can impact the ideal overhang for decking. Above all, the major influence on what is a suitable amount of overhang is safety. But there are lots of things that affect how safe decking will be. In particular, the type of wood and length of wood that you use for the joists will affect this. 

The type of wood that is used to make the joists for the decking is incredibly important because different types of woods will have different strengths and densities. Due to this, some woods will be better able to support an overhang than others. For example, some types of pine wood are able to support a much larger overhang than some other species of wood. 

But, this isn’t the only thing that will impact the suitable overhang for your decking. Other factors such as the length of the joists that you are using and the overall size of your deck will also affect the best overhang for your deck. In most cases, these different factors will work together to affect the exact overhang that you are allowed for your deck. To help you out, here’s a little more information you should know. 

Calculating the Suitable Overhang for your Deck

There are lots of different things that affect the suitable overhang for your deck, and in most cases these different factors work together to dictate what is safe. To help you calculate what is a safe overhang for your deck, we’ve put together this table to help. 

Joist Spacing12 Inches16 Inches24 Inches
Species SizeAllowable OverhangAllowable OverhangAllowable Overhang
Southern Pine2 × 6
2 × 8
2 × 10
2 × 12
1 ft 0 in
1 ft 10 in
3 ft 1 in
4 ft 6 in
1 ft 1 in
2 ft 0 in
3 ft 5 in
4 ft 2 in
1 ft 4 in
2 ft 4 in
2 ft 10 in
3 ft 4 in
Spruce Pine-Fir, Hem-Fir, Douglas Fir-Larch2 × 6
2 × 8
2 × 10
2 × 12
0 ft 11 in
1 ft 8 in
2 ft 10 in
4 ft 4 in
1 ft 0 in
1 ft 10 in
3 ft 2 in
3 ft 11 in
1 ft 2 in
2 ft 2 in
2 ft 9 in
3 ft 3 in
Western Cedars, Redwood, Red Pine, Ponderosa Pine2 × 6
2 × 8
2 × 10
2 × 12
0 ft 9 in
1 ft 5 in 
2 ft 5 in
3 ft 7 in
0 ft 10 in
1 ft 7 in
2 ft 7 in 
3 ft 9 in
0 ft 11 in
1 ft 9 in
2 ft 8 in
3 ft 1 in

Summary

In short, the distance that your deck can overhang the joists that are holding it up will depend on the type of wood that you are using for the joists, and their dimensions. To calculate the safe overhang for your deck, check out the table that we have put together above.