Whenever I think of Building a Deck, the framing process is always what comes to mind. And this makes sense because framing the deck is 70% of the entire deck building process!

The good news is that deck framing is not inherently difficult. The bad news is that you will be working with large lumber (and a lot of it). 

Pro Tip: Deck framing goes much more smoothly if you have a second set of hands helping you. However, it is possible to frame a deck entirely by yourself (which is what I had to do for this 95% of this deck). 

Note that the deck framing process is sometimes easier to understand visually. So if you are more of a visual learner, consider watching my “How to Frame a Deck YouTube Video” Linked below. 

Now this is a long article becasue it is very detailed (so bear with me) – Let’s begin!

Tools and Materials Needed to Frame a Deck

Below are some of the most common tools and materials that will be needed to frame a deck: 

• Pressure Treated Lumber (Various types and sizes) 
• Ledgertite Screws (for attaching the ledger board to the House)
• Flashing Tape (To waterproof crucial connections)
• Joist Hangers
• Joist Hanger Hardware
• Rafter / Hurricane Ties
• 3” exterior rated screws
• Framing Nailer (Optional)

Deck Framing “Anatomy” (Understanding all the Components) 

Before you can actually frame a deck, you must ensure that you understand all of the deck framing components. Refer to the image below which illustrates all of the framing components for a typical deck. 

Within this article, I am going to show you how to install each of the deck components in the image above so that you can frame you deck like a professional. 

How to Install a Deck Ledger Board

The ledger board is the horizontal framing member that attaches to your house and carries one end of your joists. It’s one of the most critical structural elements of the deck – as it is also the most common “failure point” for decks. 

If the ledger fails, the deck fails.
If the ledger isn’t flashed properly, the house rots.

Lovely… 

You are going to be attaching your Ledger Board to your home’s existing Rim Joist – so you need to ensure that the rim joist is in good condition. If you are replacing an existing deck, remove the old ledger board and flashing and inspect the Rim Joist. If you are building a new Deck from Scratch, your home’s Rim joist is likely in good condition – but you will likely need to remove the siding and flashing to access it.  Fortunately, my home’s rim joist is still in good condition – so we can proceed with the ledger board installation process. 

PRO TIP: If your home’s Rim joist is fully rotted out, you have a repair job on your hands that is beyond the scope of this article. However, there is a way to frame a deck without a ledger board. To do this, you will actually install a Beam directly at the house. Instead of attaching the Joists to your house, this Beam will support the joists instead – giving you a “freestanding” deck. Refer to the image below. 

Waterproofing Your Home’s Rim Joist

Before you even think about hanging the ledger board, your want to protect the home’s Rim Joist from water. There are many different waterproofing membranes / flashings that you can use to accomplish this, but I applied a peel-and-stick underlayment (GAF ice-and-water style membrane) directly to the rim joist of the house:

The goal here is simple – If water ever gets behind our ledger, we want it to contact our waterproof membrane, not our home’s Rim Joist (or the structural lumber behind it!).

Once the flashing is applied, we can mark the height for the ledger board. 

Setting the Ledger Board Height

To set the height of the ledger board, I like to use a laser level. 

I like to set my Ledger Board 2”-3” below the door threshold for the following reasons: 

• This will give space for our 1” decking boards to be installed on top of the ledger board and joists. 
• The additional 2″ drop helps ensure that under heavy rain, water doesn’t sneak into the house.

Adjust your laser level so that the projected level line is ~3” below the door threshold. This will be the mounting height for the top of the ledger board. 

Pro Tip: Laser levels are amazing… until the batteries die, sunlight washes them out, or someone bumps into them. Always snap a chalk line once you’re happy with the laser projection.

Installing the Ledger Board

Ledger boards are typically 2×8”, 2×10”, or 2×12” pressure-treated lumber. Typically, your ledger board size will match your joist size. 

Before installing the ledger board (or any board on your deck), you will want to “crown” your lumber (more on that in the joist section). For now, just know: crown up.

Below are the Steps for Hanging the Leger Board: 

Tack the Ledger Board in Place with a Framing Nailer and Double Check level using a 6’ level (having a second person is very helpful)

These 3” framing nails are temporary – The real structural connection comes later with ledger screws or structural fasteners.

Ledger Board Waterproofing and Flashing 

With the Ledger board tacked in place, it’s time to waterproof the ledger like our long-term happiness depends on it… because it does.

Flashing on Top of the Ledger

First, I apply a 6″ wide strip of flashing tape on top of the ledger board:

Ledger “Z” Flashing (Metal or Vinyl)

Next comes the main piece of flashing that covers the joint between the wall and the ledger:

I’m using metal flashing because that’s what was available locally, but vinyl is often easier to work with (you can cut it with scissors or a utility knife).

I fasten the flashing to the wall every 18″–24″ or so using a roofing nailer (or just a hammer and roofing nails).

If your deck is longer than 8′, you’ll likely need multiple pieces of flashing. To Join two pieces of flashing together:

This way, any water that runs along the flashing will flow over the joint, not under it.

Final Flashing Layer — Joist Tape Over Nail Holes

Now you might be thinking:

“Okay, now there are nail holes in the flashing. Isn’t that a problem?”

Well, yes… that’s why I run a final piece of joist tape (flashing tape) along the top of the ledger and over the nail line of the metal flashing. This will Seal the nail penetrations and add one final waterproof layer.

Structurally Fastening the Ledger

With the ledger board waterproofed, it’s time to make the ledger structural.

I’m using PowerPro LedgerTite screws, 3⅝” long. These are structural screws specifically designed for securing ledger boards.

General best practices (always check your specific code and manufacturer instructions):

• Follow spacing and pattern requirements from your local code / deck guide.
• I installed the screws roughly every 12″–16″, with two screws between each joist bay, staggered vertically (one high, one low).

Before driving these screws, I highly recommend that you mark your 16” O.C. Joist Spacing on your Ledger Board before installing the structural screws

This saves you from trying to drive joist hanger nails into hardened structural screws later.

At this point, the ledger board has been secured with structural screws and we can begin installing the Posts and Beams.  

How to Install the Deck Posts and Beams (Building the Primary Support Structure)

With the ledger in place, we shift our focus to the outer support system: posts and beams.

Setting The Post Height Using a Laser Level

The goal is for the top of each beam to be at the same height as the bottom of the ledger board – this way your joists will sit level from the house to the beam.

Since we’re using 2×8 joists, the bottom of the joist aligns with the bottom of the ledger. That’s our reference point for post height. 

First, establish a laser line that is even with the bottom of the Ledger Board .

Below are the Steps that I used to mark my Post Height: 

Stand a 6×6 post in the post base hardware on the concrete footer. Use a Post Level to make sure the Posts are perfectly Plumb. 

Mark where the laser line intersects with the post and mark where the line hits the post. 

That mark indicates where the bottom of the joist needs to be, and will indicate the cut line for your post. 

Cut the posts to height with a miter saw—usually cutting one side, then flipping and cutting the other side of the post is required to the 6”×6” thickness.

On this deck, I chose 6”×6” posts instead of 4”×4” posts for added stiffness and peace of mind, especially considering the future load of a hot tub.

Beam Connection Methods – Why Notching Wins

Next up, we need to think about how we are going to attach the beams to the posts.

There are three common methods:

1. Side mounting beams to the post with hardware (DO NOT USE)
   • Beam is bolted to the side of the post
   • Puts a lot of stress on the hardware
   • Less direct load transfer
   • Increasingly frowned upon or prohibited in many jurisdictions

1. Sitting the beam directly on top of the post with hardware
   • Good load transfer (beam bearing on post)
   • Uses post caps or similar hardware

1. Notching the post and nesting the beam in the notch
   • Beam bears directly on the remaining post section
   • Provides excellent load transfer and lateral restraint
   • Strong, clean, and my preferred method

For this deck, we’re using the third method: notched posts.

For more information on the various options for attaching the Deck Beam to a Post, Check out my Blog Article Linked here. 

Notching the 6”×6” Posts for the Double 2×10 Beam

For my deck, I am using a beam made from two 2×10 boards (called a double 2×10)

Note that there are many different deck beam size options and that you may want to use a different deck beam type / size for your deck. 

Measuring the Notch

First, determine the actual depth of your beam:

Then:

1. Mark 9½” down from the top of the post on the face.
2. Transfer that mark around both sides of the post to outline the height of the notch.
3. Next, mark the thickness of the beam notch:
   • Each 2×10 is about 1½” thick
   • So, two together = 3″ total
   • I marked 3¼” to give just a hair of extra clearance so the beam would “nest” easily.

You’re essentially drawing a 3″ (or 3¼”) deep by 9½” tall rectangle on the top side of each post.

Cutting the Notch

To cut the notch, follow the process below:

First, cut the Beam Notch Using a Circular Saw. Next, finish the cut using a reciprocating saw.

Finally, I also trimmed about ½” from the top of the post so the beam would sit slightly proud of the post, rather than the post sticking above the beam.

Treating Cut Ends of Pressure-Treated Lumber

Any time you cut pressure-treated lumber, it is recommended that you apply an end-cut treatment (a liquid wood preservative for PT lumber) to all fresh cuts.This helps maintain rot resistance where the factory treatment has been cut away.

Assembling and Installing the Beams

Once the posts are notched and ready, we bring in the beams.

Building the Beam

• Pick two 2×10s that are similar in depth.
• Lay them side by side and line them up.
• Nail them together with 3″ framing nails (space them every 16″–24″).
• You can come back later and add structural screws, but nails are fine to get everything in position.

Next, it’s time lift the Beams and position them in place. This is a two-person lift if you can get help. If not, move methodically and be prepared for some awkward (and Heavy) moments.

• Set the beams on the notches at the tops of the posts.
• Make minor adjustments so the edges line up with your layout.
• Ensure each beam segment has any splices directly over posts, per code.

What matters is that when you’re done:

• The beam is fully seated in each notch.
• The tops of the beams line up level with the ledger board.
• All posts are still plumb.

Securing the Beams to the Posts

There are two Primary methods for attaching the Beams to the Posts:

Old-school method:

• Drill a ⅝” hole through the beam and post.
• Use ½” carriage bolts with washers and nuts.
• Tighten everything down.

Modern method (which I used):

• Use Thru-Lok style structural fasteners
• No pre-drilling required.
• Drive from one side, add washers and nuts as required, and tighten from the screw side.

You’ll need:

• Two fasteners per post-beam connection,
• Or four where there’s a beam splice at the post.

Before tightening everything down, use a post level to confirm your posts are plumb in both directions.

Finally, to help extend the life of the beam, Apply a strip of 6″ flashing tape over the top of the double 2×10 beam.

This prevents water from sitting between the two boards, which could otherwise encourage rot over time.

With the Beams in place and waterproofed, it’s time to install the Joists. 

How to Install the Deck Joists

If you didn’t mark you joist spacing as part of the ledger board installation, you will want to mark all of your joist locations now. Joists are typically installed 16” On Center (O.C.) but sometimes 12” O.C. (or even 24” O.C. Joist Spacing is used). 

I Highly Recommend that You Mark all of you Joist Locations on the Ledger Board and Your Beam Before you Install the First Joist

It’s a good idea to mark both the Ledger Board and the Beam at the same time to ensure that all of your joists are spaced evenly and marked in the right place. 

Starting with the Outermost Joist

I start with the outermost joist, because:

• It defines the outer edge of the deck.
• It’s used as a reference to square the whole joist layout.

For the outermost joist:

This outermost joist needs to be perfectly perpendicular to the ledger.

To confirm that, I used the 3-4-5- triangle method:

Ensure that the Outermost Joist Is Perfectly Square from the House by using the Right Triangle Method (3-4-5, 6-8-10, etc.) 

Every joist must be crowned before installation – here is what that means..

Crowning the Joists

• Look down the long edge of the board.
• Identify the slight “arch” or bow.
• Install all joists with the crown facing up.

If some joists are crowned up and some crowned down, your finished deck surface will have humps and dips. Not good…

The Best Joist Installation Method (In My Opinion)

After trying a few awkward methods (like trying to hold the joist in the hanger and nail it at the same time), I landed on a simple, efficient process:

1. Place the joist at the ledger so the top of the joist is flush with the top of the ledger board.
2. Align the joist with your layout line on the ledger.
3. Shoot a framing nail through the top of the joist into the ledger. This acts as a temporary clamp.

4. Now the joist is hanging hands-free exactly where it needs to be.
5. Take your time and install the joist hanger around the joist:
   • Use the necessary nails or structural screws per joist hanger manufacturer’s requirements
   • I used a combination of joist hanger nails and screws

On the beam side:

• Use hurricane ties or other approved connectors to secure the joist to the beam.

Use Hurricane Ties (or Joist Hangers) to attach the Joists to the Beams (Ensure 16” O.C. Spacing that matches the ledger board layout

Repeat for each joist:

• Crown up
• Align with layout
• Tack from the top
• Install hanger
• Secure to beam

It’s repetitive, but once you get into a rhythm, it goes quickly.

Multi-Beam / Multi-Span Joist Strategies

Most decks just have one beam and a single span – But for my deck, I installed multiple beams to support a future Hot-Tub. To do this, I “sistered” the joists together on the first beam and then used additional hurricane ties to secure the joist to the additional beams. 

I “Sistered” the Joists Together on the First Beam

I used additional Hurricane Ties, etc. as needed to secure the Joists to the additional Beams

Cutting the Ends of the Joists to Size (If Needed)

I typically like to leave all of my joists long and “un-cut” until I install my decking boards. So I will cover this more during the “Decking Installation” Section. However, you will likely need to cut the end of your joists at some point. I like to mark all of the cut locations on the joists and then cut them to size (from above), using a circular saw. 

As noted, I will go into more detail on the best method for cutting the joists in the “Decking” section of this Ebook. 

Installing the Rim Joist

Once all joists are cut to the correct length, you will need to install the Rim Joist. Below is the best way to install a rim joist if you are working Alone: 

Tack a Piece of Scrap Wood to the Boom of the Joist to help hold the Rim Joist in Place while you install It

2. Lift the rim joist into position and rest it on the blocking.
3. Nail the rim joist to the end of each stud using a framing nailer.

4. Later, go back and add screws for extra peace of mind.

If the rim joist needs to be spliced:

• Install blocking at the joint so each rim piece has full bearing at the connection point (Refer to the left side of the image above)

Crown the rim joist and treat any cut ends with end-cut preservative, just like the other structural members.

How To Install Deck Blocking

Before we walk away from framing, there are a few locations where support “blocking” should be installed. 

Mid-Span Blocking

If your joist span exceeds about 8 feet, it’s recommended to add blocking between the joists. The blocking will:

• Reduce twisting and racking
• Help distribute loads
• Make the deck feel more solid underfoot

I like to stagger the blocking so it’s easier to nail, but you can also toe-nail or use screws from the side.

Horizontal Blocking for Railing Posts

If you are going to be installing a railing or if you are going to be “Picture Framing” your deck (discussed in more detail later), I highly recommend that you consider installing flat blocking around the perimeter of your deck. 

On previous decks, I skipped this step and I had to crawl underneath the Deck to add blocking directly under railing posts… It worked, but it was a pain.

On this deck, I pre-installed horizontal blocking everywhere that I’d need railing posts.

If your deck is longer than your decking boards (e.g., > 16′), you may want to use a breaker board instead of butt joints (discussed more in the next section).

To support a breaker board:

• Install extra blocking at the breaker board location
• This ensures each end of the decking boards and the breaker board itself have solid support.

By planning this during framing, you avoid awkward retrofits later.

Installing Joist Tape and Final Waterproofing (Don’t skip!)

Although Pressure-treated lumber might last 20–25 years, Composite decking often has warranties around 30–35 years. So to try and make our pressure treated lumber last as long as the composite decking above it, I recommend installing joist tape. 

Joist tape is applied to the top of the joists and helps to shed water and moisture away from the wood. Trapped water between the joists and the decking is the biggest cause of rot – so this joist tape will help a ton. 

Additionally Ensure that you apply waterproofing to all of your flat blocking as well. 

Run all of your waterproofing flashing continuously over all of your blocking and breaker board supports too.

Will joist tape magically add decades of life to your deck? Hard to prove. But in the context of the time and money invested into a big deck, a few extra rolls of tape feel like a smart insurance policy. If you want more of an explanation on if joist tape is actually worth it, you can check out my Blog Article Linked here. 

Conclusion

At this point, you know exactly how to frame a deck from start to finish! Although no part of the deck framing process is exceptionally difficult, it takes quite a lot of work to frame a deck (especially if you are working by yourself). 

Although this article give a good overview of the entire deck framing process, I highly encourage you to watch my “How to Frame a Deck from Start to Finish” YouTube video linked below: 

This video showcases the entire deck framing process and I can all but guarantee that it will help you to avoid making common mistakes. 

I hope this article helped! If you would like additional information on Deck Building, check out my “How to Build a Deck” YouTube series. I promise that it will be super helpful. 

DISCLAIMER: This is a reference guide only. Consult local code requirements. Links included in this article might be affiliate links. If you purchase a product or service with the links that I provide, I may receive a small commission. There is no additional charge to you! Thank you for supporting ATimprovements so I can continue to provide you with free content each week!