The moment you have all been waiting for! The DIY outdoor sofa tutorial. First, I want to say thank you to everyone who has commented and given me such positive feedback on the sofas! I can’t express how much your support means to me. Thank you from the bottom of my heart! This DIY modern outdoor sofa is a fairly easy DIY project that will elevate your outdoor space and give you a great place to relax! Now, onto the highly requested outdoor sofa plans! The best part is they are free plans 😉
DIY Outdoor Sofa Tutorial
First things first. In order to build my outdoor sofa, you are going to need lumber. When I originally built our patio furniture, my local hardware store did not carry the 6×6 timbers I used for the sides of the sofa aka the arms. So I purchased mine from a local lumber yard. I have since seen 6x6s at Home Depot.
I should also mention that I ordered all of the wood for the outdoor furniture pieces (the two sofas and the dining table) at the same time and had it delivered because a) all that lumber would not fit in my Honda Fit 😉 and B) those timbers are pretty heavy. For one sofa you will need the following items to build the couch as I did.
All lumber sizes are noted as common sizes in inches x inches x feet.
DIY Outdoor Sofa Supply List
3 – 6x6x10 Timbers*
2 – 2x8x12 Boards
1 – 12in Sliding Miter Saw
8 – 2x6in L Angle Brackets
1pk – #8 1 1/4in construction screws
1pk – GRK 5/16in x 5-1/8in Structural Screws
1 – 3/4 in Spade Drill Bit
1 – Impact Driver and Drill **
1 – Impact Driver Extender
1 – Belt Sander
1 – Orbital Sander
1gal – PPG Timeless Semi Solid Exterior Stain in Chestnut Brown
1 – Speed Square
1 – Tape Measure
1 – Safety Glasses
1 – Work Gloves
3 – Deep Seat Outdoor Cushions
3 – Outdoor Back Cushions
Note, this picture is all the wood I used to build the dining table and both sofas. I originally wanted to build an outdoor bench as well but decided against it. I ordered sizes that minimized the waste based on this. If you choose to build more than just one sofa, it might be more cost effective to purchase different lengths.
*I used smooth swan Douglas fir timbers. Mine were not pressure treated, however, I do recommend using pressure treated wood. This was the biggest mistake I made on this project because our wood has since produced sap. I have been able to clean it with a wet rag once it dries but I am looking for a more permanent solution.
**Make sure both your impact driver and your drill each have fully charged batteries and have an extra standing by if possible. You will need them.
Know before you build
If you are not an experienced builder you may not be familiar with wood sizing. Common wood sizes such as a 6×6 are not actually 6 inches by 6 inches, they are 5.5 inches by 5.5 inches. If you prefer a smaller size like a love seat or a larger size like an outdoor sectional sofa, you will need to account for this in your measurements. Always double check the actual dimensions of your lumber before making cuts.
Cut the 6x6s to size. You will need to cut the 6x6s into 8 pieces, each 32 inches long. These will be the side pieces or the sofa arms. I used my 12 inch miter saw to cut these but the blade is not large enough to cut all the way through in one pass. So if you are in the same boat, you will have to rotate the wood until the blade goes all the way through.
Below is a video clip of how I cut ours. This will not produce a perfect cut, however, you will be sanding them a lot if you want to achieve the same look I have.
You will not be able to make this cut with a circular saw unless you have access to a timber circular saw. A circular saw will come close, depending on the size of your blade, but even after rotating you will still have a little bit leftover that you will need to cut with a hand saw or reciprocating saw.
Measure and cut the 2x8s for the seat base and the back of the sofa. I HIGHLY recommend purchasing your sofa cushions before starting this step. I used these seat cushions and back pillows. If you choose different cushions, you will need to adjust your measurements to accommodate the size of the cushions. This is why you should have the cushions on hand prior to making any cuts in this step.
Based on the size of my seat cushions (22w x 24d), I cut the 2x8s to 67 inches long. You will need three 2x8s that will span the entire couch for center support and one 2×8 for the back support, all cut to the same length.
Sand all the wood smooth. I used my orbital sander on the flat surfaces of the pieces of wood and the timbers.
Then I sanded all the edges of the timbers with a belt sander to create a bevel. This can also be achieved with a router, but when I built these I did not have one.
I wish I could say this was a quick sand but it was not. This part was far from fun but gave the pieces a lot more character in my opinion. If you have never used a belt sander before I highly recommend you practice on some scrap wood first. They are pretty powerful and can damage your wood quickly if you are not careful.
Attaching your timbers for the sofa arms. This part is a little tricky, so pay attention. I attached the timbers for the arms with screws, but before you drill any holes, determine the orientation you want for your wood. Meaning, if not all your pieces look the same on all sides or have a blemish you don’t want seen, stack them up the way you want to see them. Then when you are satisfied, flip each piece upside down and number them on the bottom so you remember the order.
You will be drilling holes to attach the pieces from the bottom side of each block. This way none of the screws or holes will be seen when fully assembled.
To begin, use the 3/4 inch spade drill bit to drill 4 staggered holes into block two about 3 inches deep (I actually measured mine every time so they would be the same). Remember, these are all upside down right now so you are drilling into the bottom of piece 2.
Word of caution. These timbers are pretty heavy duty and take some serious force to drill into. Wear gloves and hold onto your drill tight so it doesn’t pull you unexpectedly or swing around and hit you. As I mentioned above, you will need a fully charged battery for your drill as this drains the battery pretty quick.
Now stack block two (still upside down) onto block one (also upside down). Make sure all edges are lined up and it is positioned to your liking. Then use the GRK screws to attach the two pieces. Since the holes are drilled 3 inches deep, your screw will go through block two into block one securing them together. Note, if you choose to use different screws to attach the blocks, you may have to drill different size holes.
I chose to use the GRK screws because they are an alternative to lag screws. The entire sofa is fairly heavy and lag screws are usually the best way, but because of the depth, these were a better idea and easier to work with.
I found the impact driver to work best for this part since you are driving the screw through 5 1/8 inches of wood, about 2 1/2 inches on each block.
From a diagram perspective, this is what you are ultimately doing.
Once you have attached block two to block one, drill your holes in block three making sure to stagger them so they DO NOT line up with the holes you drilled in block two. To avoid confusion, I only drilled holes into one block at a time.
Once you have drilled the holes, stack block three on top of block two and use the screws to attach them as you did above. Repeat with the remaining block four.
When you have attached all the arm pieces only the bottom piece will have holes that can be seen from the underside. The top piece will not have any holes or screws visible.
Once all the blocks are attached you can flip the arm over and repeat for the second arm.
Stain all the wood. I used an exterior deck stain to seal and stain the wood. This particular wood stain applied like a stain but cleaned up like a water based paint with just soap and water. A HUGE plus in my book.
I used the stain version of my favorite brush to apply the stain. And I used Dawn dish soap and a paint brush comb to clean my brush when I was done. Although this stain was not super smelly, I stained the pieces in the garage on some folding tables I had in the basement.
I applied one liberal coat to all sides and allowed 24 hrs of dry time on each side. BTW, please don’t judge me for our messy garage! The garage is on our list of spaces to overhaul someday, but for some reason it’s not high on my priority list, haha! 🙂
Assembly. Note, these sofas are VERY heavy! I HIGHLY recommend assembling them where they will sit permanently. I made the mistake of building the first sofa in the garage and then I had to enlist a few people to help move it to the backyard. So the second sofa was assembled in place on the patio.
Lay each arm on the ground next to each other and lay out the support brackets for the seat slats. In the photo below, the inside timbers are the bottoms of each arm. I attached the brackets just above the bottom timber based on the height of my cushions. You will also want to consider the total depth of your cushions when spacing the brackets. The placement of each bracket should be the same on the right arm and the left arm. If not, your sofa will be crooked. This means measure them 🙂
I used #8 1 1/4in construction screws to attach the brackets.
Once the brackets are attached to each arm, stand them up and use a scrap piece of wood to prop them up. You will need to be able to lay underneath the sofa to attach the seat supports.
Then lay three 2x8s across the brackets. Make sure everything is straight and square. Also, the distance from the edge of the front 2×8 to the edge of the back 2×8 should equal the depth of your cushions. Once everything is lined up, lay on the ground under the sofa and attach the brackets to the bottom of the seat supports with the same screws used above.
For this part, I sat on the boards to keep them in place while Barry screwed them in from underneath.
Attaching the back slats is very similar, but I HIGHLY suggest placing your seat cushions and sitting on your sofa before deciding where to put the back support, which is exactly what I did.
Once I felt comfortable with it, I attached the first bracket with one screw not fully tightened straight up and down. By doing this, I could hold up the 2×8 and swing the bracket back and forth to help decide what angle to use. This was a two person job so I do not have photos. Theoretically, you could leave them straight, but I wanted a more lounge like feel.
Once I decided on a slight angle, I used the speed square to position each bracket at the same angle. I used a 35 degree angle. Then I attached the last 2×8 back piece to the brackets. You can use any degree angles you would like or none at all.
To save yourself some headache, I do recommend drilling pilot holes for the brackets so none of the wood splits.
The last piece of this build step is to add cushions and pillows for those finishing touches! I purchased pre-made cushions because my sewing skills are sub par at best, but you could definitely do custom cushions or pillows.
Final step! Sit back, relax, and have a great time enjoying your very own outdoor sofa! This modern outdoor couch is the perfect addition to your outdoor living space and a great way to get started with DIY. With mostly basic tools and solid wood you can have your own DIY sofa that definitely won’t blow away in the wind!
This modern design was inspired by a high end version sold by Restoration Hardware. I couldn’t afford to buy it for $20k so I found away to make it! The total cost to build was about $230 a sofa. Now I have a beautiful modern sofa with clean lines to soak up the summer on my back porch. The perfect place to enjoy good friends and food!
Check out the full reveal of the Backyard Makeover with source list here. You can also make the matching Outdoor Dining Table with Full Tutorial here. Curious how my DIY Outdoor Sofas are holding up? Check out my two year update and frequently asked questions here.
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