Building a Multi-Level Deck: What You Need to Know (Updated 2021)

Decks are some of the best features that a house can offer. After all, they offer a living space outdoors, where you can enjoy nature without having to leave the comforts you’ve grown accustomed to. They can also allow you to host some great barbeques and other outdoor parties for your friends and family.

A multi-level deck can take things to the next level. This type of deck is interesting to look at, and can help you demarcate the outdoor activities you want to do. For example, one level can be for barbecues and hanging out, while another level can be where the hot tub is installed.

Thus, building a multi-level deck can definitely be more than worth it.

Tools for Building a Multi-Level Deck

Do you have the tools for building the multi-level deck you’ve always wanted? Will you need more tools than usual because multi-level decks are more complicated to build?

The good news is that if you’re a profligate DIYer, you probably already have the tools you need for this project. Plus, if you need machinery and other equipment, you’ll be able to rent them for a certain period of time. If there are any tools that you might not have yet, check out Engineer Warehouse to see if you’ll find them there.

Here are the tools you might need for this project:

Protective Equipment

• Safety goggles
• Ear plugs, best used when using power tools
• Dust mark, should be designed for users handling timber
• Protective gloves
• Rigger gloves

Site Preparation

• Tape measure
• Measuring wheel
• Twine
• Wooden pegs
• Club hammer
• Spirit level (450 mm or longer) or a laser level
• Spade
• Spray paint
• Weed control fiber
• Gravel
• Concrete tubes
• Quick-drying concrete
• Cement mixer
• Construction calculator

Installing the Ledger Board

• Nails
• Carriage bolts
• Flashing

Building the Frame and Decking

• J-bolts
• Post brackets
• Joist hangers
• Palm nailer
• Hurricane ties
• Beams
• Joists
• Coach screws
• Coach bolts
• Socket set
• Combi drill
• Combination square or angle finder
• Decking boards
• Decking screws
• Waterproofing membrane

Cutting and Prepping Wooden Decking Boards

• Pencil
• Mitre saw
• Circular saw
• Jigsaw
• Workbench
• Sander
• Decking and grain protector
• Wood preservative
• Paintbrush

Decking Materials You Can Use

You have a lot of choices of decking materials, and each one has its own pros and cons. Typically, deck boards are lumber, but you also have other options like wood alternatives or metal.

Before you make your choice, you’ll have to consider factors like insect resistance, appearance, durability, cost, and workability. Here are some decking material options that you might want to look into so you can make an informed choice:

Building a Multi-Level Deck

Multi-level decks aren’t the simplest deck type out there. However, they’re still doable, even though they’ll take some more time and effort to build. Here you’ll find a guide for building an attached two-level deck with picture framing on a slope.

 

Slopes present some challenges to deck-building endeavors.

A lot of properties are built on slopes, which can afford residents a great view, depending on where the property is located. However, the downside with slopes is that you can’t really do much on them.

Level spaces are better as living spaces, and building a deck is a great way to put level areas in slopes. This guide can give you an idea on how to best utilize sloping spaces.

1. Draw a Plan

When you have your property’s measurements and the measurements of the area you want to build on, you can start drawing up a plan that you can base your deck on. You can do a rough sketch of the deck design you want, but if you have the skills and know-how, you can come up with a more detailed design.

For example, you can do a scaled drawing with the help of drafting tools.

There are also computer programs you can use to make drawings of the deck design you want.

2. Prepare the Site

Decks are best built on a flat and level area. Thus, if you’re planning on building a deck on a slope, you’ll have to excavate soil to form a level building area.

Depending on how much material you need to move, you might need to rent and use excavation equipment to make the task easier and quicker to do. If you’re planning on building a two-level deck on a slope, you might need to use equipment other than hand tools like shovels or spades. 

Remember that if you do not know how to use the necessary machinery and equipment, it’s best to hire a professional that can do the job for you.

Once you’ve moved enough material, you can begin to work on leveling the area further. Tamp down the soil so the surface is smooth and there aren’t any loose soil and small rocks. You can use a spirit level or a laser level to check if the surface is sufficiently level.

Once the area has been sufficiently prepped and cleaned, you can use wooden pegs to mark the corners of the deck. Take a roll of twine, tie one end to one corner, then roll and stretch the twine out to the other pegs in order to form a perimeter, which indicates the span of the deck. Using a builders square or an angle finder, check to see if all the corners are 90 degrees.

3. Dig and Fill the Footing Holes

At this stage, you’ll need to start digging the footing holes. First, find the spots where the footing holes should be and mark them with spray paint. Then, you can start digging.

There are a couple of ways you can do this. One option is to dig the holes with a shovel, another is to use a post hole digger. Another option is a hydraulic auger, which is a piece of machinery that allows you to dig holes in the ground more quickly and easily. You can ask your contractor if using one is necessary.

You might even end up using all three.

Once the footing holes have been dug up, make sure they don’t have any loose stones or pebbles inside them. Take a concrete tube or two, depending on how many footing holes you have, and cut them up to form shorter tubes. These will go into the footing holes.

Once they’re in, check to see if each tube is level. 

The bottom of the holes should be filled with gravel or crushed rocks for drainage. Start mixing up concrete to fill the holes.

Filling the footing holes will go differently for the holes meant for the upper deck level and holes meant for the lower deck level. The footing holes for the upper level will support wooden posts. Make sure that these wooden posts are plumb before you fill the holes with concrete.

Lower Deck Level Footing Holes

The footing holes for the lower deck level, meanwhile, will have metal brackets and no posts. This is because in this plan, the lower deck level is low to the leveled ground. The brackets will support the beams that will in turn support the joists of the lower deck level.

Once you’ve filled the lower deck level footing holes with concrete, use a piece of wood to screed the excess concrete off the top and make a smooth surface. Then, push a J-bolt into the concrete, with the bolt end sticking out. Do this for all the footing holes meant for the lower deck level.

Before you do this, make sure to determine the exact spot where your J-bolt should be. You can use the wall of the house as a reference point to determine the exact spot of the J-bolts, and consequently where the brackets and beams should end up. To mark these spots, you can stretch the twine over the J-bolt spots. Make sure that the twine is tied to two pegs on opposite ends of the line of footing holes. 

4. Attach the Ledger Board

The concrete used in the footing holes will take some time to cure and harden. While you wait, you can start installing the ledger board for the upper deck.

In this plan, the upper deck is attached to the house. The process of attaching the ledger board depends on your house’s exterior finish. If, for example, your house has a stucco exterior, you might want to reconsider attaching a ledger board unless you’re fine with cutting into the stucco. If the house has siding as its cladding material, however, you’ll just have to take out siding boards and hardware in the spot where the ledger should go.

Waterproofing is also an important aspect to installing ledgers. You want to make sure that in the process of installing the ledger board, you won’t leave the framing of the house prone to moisture. Installing membrane flashing behind the ledger should be able to prevent moisture from damaging the house framing.

Check to see if the ledger board is level. Once you’ve attached the ledger board and everything is in order, mark the spots where you’ll be attaching the joists.

5. Install the Beams

When the concrete in the footing holes has cured and hardened, you can start installing the beams. First, secure the brackets on the J-bolt in the lower deck level footings. After this, lay down the weed control fabric, leaving holes for the brackets and posts. The weed control fabric will prevent weeds from growing through your deck. You can then pour and spread gravel over the fabric.

Start with the beams for the upper deck. Attach a deck post bracket to each of the upper deck posts and secure them with screws wherever you can. Once the brackets are attached, you can place the post caps and put the beams in the brackets. For security and stability, screw the brackets into the beams wherever you can as well.

For more stability, you can use earthquake brackets and install them where two beams meet end to end. This isn’t technically necessary, but it’s a good way to secure your beams even more.

The same can be done to the brackets for the lower deck level footings. At this point, all the beams for both the upper and lower deck levels should be in place. Check once again to see if the beams are level.

The lumber for the beams, specifically those for the lower deck level, should be rated for ground contact. However, for extra protection, you can also cover the lower deck level beams with metal sheeting on both sides. This will help prevent rot and damage, which will in turn allow your deck to last for a long time.

6. Install the Upper Deck Level Joists

You can now install the joists for the upper deck level. You can start by installing the joist hangers on the ledger board, at the spots you marked out earlier.

To make sure that the joists will fit into the hangers, you can take a piece of wood cut from a joist and use it to space the two hanger jaws correctly. Use a palm nailer to make this task easier.

Once all the joist hangers are in place, you can start installing all the joists. To secure the other ends of the joists into place, you can use hurricane ties that you can nail to the beam. This will make sure that your joists won’t slide out of place.

It’s also at this point that you can install drip edge flashing, which should go under any windows or doors, but over the ledger board. Glue the flashing with silicone sealant, then reinforce it further with flathead nails.

Once the flashing is in place, you can start nailing the joist hangers and hurricane ties into the sides of the joists.

7. Install the Joist Rim and Reinforcements

It’s best to measure and cut your joists so that they’re the right size and they’ll be able to accommodate the thickness of the rim joist. Otherwise, you’ll have to measure the thickness of the rim joist, then cut that same length off the joists one by one. This can be done with  a circular saw.

If you do cut your joists while they’re in place, don’t forget to apply wood preservative on the cut edge.

You’ll now be able to attach your rim joist. You can use a palm nailer to nail the rim joist to each inner joist.

Now, because this deck will have a picture frame, the joists need to be doubled up in certain spots, like the ends and the middle. These spots are where the border boards for the decking will go.

Picture framing is not only aesthetically pleasing, it’s also advisable for longer decks. It can break up the decking into parts, which means you won’t need to use long pieces of lumber.

When all this is done, you might want to consider applying waterproofing membrane tape on the tops of the inner and rim joists, as well as over the front of the rim joist. While this step isn’t terribly important, it can help preserve your deck framing and render your deck usable for a long time to come.

8. Place the Upper Deck Level Decking

You’ll now be able to install the decking of the upper deck level. Start with the border boards before you install the rest of the decking boards.

The outer border boards will meet at the corners. You may want to cut miter edges at a 90-degree angle on one end of these border boards. This way, they’ll be able to form miter joints at the corners of the deck. Don’t forget to apply preservative on the cut edges of these boards as well.

Start fastening the border boards to the deck frame with deck screws. Once the border boards have been fastened, you can start laying down and fastening the decking boards as well. When installing decking, it’s important to use decking board spacers. This way, you can be sure that all the boards are lined up nicely.

9. Build the Lower Deck Level Frame and Decking

At this point, it’s best to get started on the deck framing for the lower deck level as well. Mark the spots where the joists should go on the beams, then nail hurricane ties into those spots. Once all the hurricane ties are in place, you can place the joists into them.

When all the lower deck level joists are secured, you can now install the rim joists. This is the same process as the installation of the rim joist in the upper deck level, but the lower deck level needs a rim joist on two sides instead of one.

Just like the upper deck level, the lower one will have picture framing as well. Thus, the joists for the lower deck level should be doubled up the same way the joists for the upper deck level were.

If you’ve applied waterproofing membrane tape on the upper deck level joists, do the same for the lower deck level joists as well.

You can now also start fastening the border boards and decking boards, which follows the same process as that of the upper deck level border boards. You’ll now have two deck levels with complete decking.

10. Install Upper Deck Level Balustrades

However, both of the deck levels aren’t complete just yet. Both levels will have railings that can increase security and make accidents less likely. The upper deck level will go first.

First, you need to install newel posts. Cut out a piece at the bottom ends of the posts so they’ll be able to fit over the deck frame and decking. See the figure below:

Also, it might be worth noting that railings are usually 42 inches tall. In this build, we’ll be attaching handrails over the newel posts. Thus, it’s best to subtract the thickness of the handrails from 42 inches, and the difference will be the height of the newel posts.

Remember to leave a space in between the balustrades for the stairs down to the lower deck level.

Once all the newel posts are in place, you can start attaching the rails. The upper rails will be installed at the same height as the newel posts. When attaching the base rail, meanwhile, you can use a spacer to ensure that you install the rail at the right height. The figure below shows how a spacer should be positioned:

You can now start attaching spindles. It’s important to check your area’s building code to see what it says about balustrades. For example, it may tell you that the spindles should be no more than 4 inches apart.

When the spindles are all in place, you can start attaching the handrails by nailing them to the newel posts. These handrails should have a miter edge at one end as well, since they’ll be forming a miter joint.

11. Attach Stair Stringers

The upper and lower deck levels are pretty far apart in this project. Some multi-level decks have levels that are close enough in height that you’ll be able to easily step from one level to another. However, in this case, stairs are necessary.

Fortunately, the two deck levels are three stair steps apart. The upper level deck will serve as the topmost step, so two further steps are needed. This also means that a stringer board is necessary.

A stringer board is where you’ll attach the stair stringers. To attach the board, you’ll first need to fasten two pieces of wood on its back, like so:

Those pieces of wood will go behind the rim joist, while the stringer board will go right under the same joist. You can attach the stringer board to the rim joist using these two pieces of wood.

Next, you need to make stair stringers. You can do this yourself with a piece of lumber and a miter saw. You’ll need three stringers for this project, and they’ll need to look like this:

You can use joist hangers to attach the stringers to the stringer board. The top of the stringers should be flush with the bottom of the rim joist. Meanwhile, you’ll also need to install stair cleats at the bottom of the stringers, in between each stringer. Attach each stringer to the cleats, then screw each cleat to the lower deck level decking. These cleats will help provide more stability to the deck stairs.

12. Build Steps and Lower Deck Level Balustrades

Once the stringers and cleats are securely in place, you can start attaching the toe kicks with screws. Afterward, you can attach the treads with screws as well.

Now, the question is whether or not both deck levels need balustrades. Typically, building codes require balusters for anything that rises higher than 30 inches above grade. In this project, the lower level is fronting a slope. For safety, it may be best that the lower level has balustrades as well.

Building the lower deck level’s balustrades actually doesn’t differ from the process of building the upper deck level’s balustrades. However, one thing that differs is the spacing of the newel posts. Check your area’s building code if there are any guidelines about how far apart newel posts should be.

And with that, you’ve built yourself a multi-level deck with picture framing, stairs, and balustrades. It’s certainly a long process, but one that can be rewarding in more ways than you realize.

Maintaining a Deck

Decks typically don’t have a long lifespan. When they hit 20 years, they might already be considered old. The lifespan of a deck can depend on how they were built and the materials and tools used to build them.

It’s therefore important that you take longevity into account even while you’re still in the building phase. You can choose, for example, pressure-treated lumber that can resist rot and damage for a long time.

You can also take some protective measures, such as using sealants, wood preservatives, waterproofing materials, and even metal sheeting to protect the deck framing against damage.

Regular checkups are also necessary. Through them, you’ll be able to catch certain problems and issues and remedy them before they get worse. These checkups are especially helpful in preventing structural damage.

Decks can be costly to build and maintain, which is why it’s important to make sure that you can handle the commitment before you build one. However, the enjoyment and other benefits you get out of a well-built and well-maintained deck will likely be worth it.