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Have you got a small deck that you’d like to make bigger? A deck extension can be a great way of adding onto a deck without a huge deck remodel. That’s what we did easily and on a budget. Our DIY deck extension was built in a weekend and we added double the space to our deck – without digging post holes or pouring concrete. Also included is how to match old deck boards to new ones, stairs, railing and skirting.
Intro by Robin Steps by Ed
The deck remodel at our weekend place is coming along so well! We’re finally sharing how we made the simple deck extension!
If you’re interested in adding onto a deck – simply – this is the post for you!
Above you can see a shot of the deck when we first purchased or riverside mobile home in the woods. (Have you been following along with our Mobile Home Makeover?)
It was a nice enough size and came with a roof over it. The roof was made well – the foundation of the deck was dubious (more on that here). We’ve been working over the last few seasons to make the deck work best for our family.
We’ve already shown you two of our deck rehab projects:
The first was when we built a super simple Hot Tub Deck for our portable hot tub.
The second was the Deck Rail Bench Seat we added onto the existing deck to create a spacious eating area.
(Update: we later added this DIY Deck Planter to upgrade the old part of the deck)
This time ’round we’re showing how we made the deck live even larger with a DIY deck extension.
Want to see what it looks like now? Of course, you do!
TA-DA!
Adding onto a Deck: How to Build a Simple Deck Extension
Steps by Ed
This deck extension works because it isn’t too high and there is an existing deck to join on to. It is built on the ground – so no holes to dig. It will move with frost heave, but the deck blocks will allow you to shim things up a bit if it goes too out of level for you.
Our extension is approximately 8′ x 14′.
Robin sometimes gives me grief (rightly so) for letting standard 8-foot stock material influence my whole design, but in this case, it really makes sense. The current deck was already 8-feet deep and the distance from its end to the hot tub worked out too.
Materials for Deck Extension:
Patio Pavers and Deck Blocks – enough to replace any piers you would normally dig. We have 9 in ours, but you can opt for more if you’re going larger or have stability concerns.
1 or 2 – 8′ x4″ x 4″ Pressure Treated (PT) posts for levelling and securing the frame in Deck Blocks – you can use leftover pieces to build the railing and the bench seat.
6 – 8′ x 2″ x 4″ PT for cross-bracing and keeping things square and plumb while assembling
6 – 8′ x 2″ x 10″ PT to sister together into beams for your deck.
Robin and Ed are a DIY-loving couple with over 25 years of design and build experience. Also, Robin is a Nutritionist and former Registered Dietitian and Ed is an award-winning Business Educator. We share strategies for living a rich life on a DIY budget: creative money-savvy ideas for a stylish home, healthy meals and family fun. Our work has been published in the pages of Do It Yourself, Farmhouse Style and Better Homes & Gardens magazines.
I just tackled my first deck by myself and I agree with the screws lol. Learned a ton and yes I had to take things apart a few times. The 2x4s used to keep everything level and square while constructing base is brilliant! I so wish I would have seen this earlier. I did a few things different but I am confident my deck will probably outlast my grands. The outcome is stunning and that bench seat! Amazing job, thank you for sharing. I am now a follower 😊
Carolyn
Saturday 26th of December 2020
I just tackled my first deck by myself and I agree with the screws lol. Learned a ton and yes I had to take things apart a few times. The 2x4s used to keep everything level and square while constructing base is brilliant! I so wish I would have seen this earlier. I did a few things different but I am confident my deck will probably outlast my grands. The outcome is stunning and that bench seat! Amazing job, thank you for sharing. I am now a follower 😊