3. Use the widest dimensions for linear quantities. I got a plan from Menard's, which is very confusing if you ask me! Deck Materials We have marked this onto the ledger and will temporarily screw a joist into position until we have marked the correct place for the post hole. If your deck is slightly out of square (different widths), calculate results for both widths, and set out each end to suit. Use sleeve anchors of a size recommended for your post base. But these can bow seriously, even if a deck is only 3 feet off the ground. To decrease … Posts Required. Work out how high you would like the balustrade to be. If you are planning on installing a hot tub or porch on top of your deck, you will usually need more footings and posts to support the additional … Post caps: £2 to £7 each: Decking lights: £15 to £40 each: Steps: £50 to £215: Decking stringer: £12 to £28 per stringer: Joists: £6 to £12 each: Weed proof membrane: £30 per pack: Postcrete: £5 a bag: Cost Factors of Installing Garden Decking. The farther a deck beam must span—that is, the farther apart the posts are—the more massive a beam must be. Use the nail gun to secure the bearer to the support post. 1. And if a deck is over 10 feet tall, you should install bracing. But there’s a lot more to know about hot tubs and decks. Or keep things simple with a complete railings kit. The standard rule for footings is that for a basic deck, the larger the beam and footing size, the fewer footings you'll need. Anyway, the deck will be 16' 2" X 17'. Most professionals will encourage you to consider going with a 6×6 deck post form the outset of the project. To prepare your support joists, measure the distance between the central support joist and the outer frame and cut sections to length. Building a deck might sound like a fairly straightforward task that anyone can accomplish, but there are a variety of elements that go into the planning stages to ensure the safety of the deck upon completion. For more on these, and other, decking accessories, check out our decking buyer's guide. For most situations, you will want to place footings and posts less than 8' apart. Learn how to install bearers and stumps for a deck with this step by step guide from Bunnings. However, if your deck will include a hot tub or roof, you must support that weight with additional footings. Repeat this process for all of the posts on your decking. Fence Calculator ; Decking Calculator; Gate Calculator; Free Quote; Quick Order; Opening Hours; Our other sites: COMMERCIAL & HIGH SECURITY; FRANCE; 0800 408 2234 Hello Sign in. Don’t set deck piers or footings above ground In the past, many decks were built with 4x4 support posts (also called structural posts). Here we are working on the top tier deck and have temporarily screwed the joist into position so that we know exactly where the holes need to be. This means that using 225 x 50mm timbers a frame 4m x 4m can be built (12ft x 12ft) using 8 posts. This article shows installing non-notched posts on top of concrete footings that rise above the ground, to support framing that has already been built on temporary supports. How to Figure Out How Many Posts You'll Need. PROStar, Brendan Casey of Casey Fence and Deck demonstrates how he saves time creating a jig to cut his deck posts. Rules like this may seem arbitrary, but they’re in place for safety purposes, and to ensure reasonable access to key parts of your home. 4. While natural wood can be used for decking frames it can defeat the object of of using long lasting maintenance free composite decking boards when your decking frame starts to rot after a few years. Use the widest dimensions for linear quantities. The packaging will tell you the size of the drill bit to use, as well as how deep to drill the holes. After all, hot tubs, full of water, and people can easily weigh over 5,000 lbs. For that reason, we strongly recommend that you use 6x6s instead, even if your building department does not demand them. Additionally, many municipalities allow 4×4 deck posts for decks up to 5’ in height. By clicking GO!, you acknowledge that you have read Trex's Privacy Policy. For that reason, we strongly recommend that you use 6x6s instead, even if your building department does not demand them. Install a post cap, also called a post-to-beam connector, onto the beam or doubled joist above; use a level to be sure it is plumb with the post base. For aesthetic or symmetry reasons, more posts may be added. Roll out your landscape fabric and cut to size, making sure it’s as snug to the posts as possible and covering all of the area under the deck. In the past, many decks were built with 4x4 support posts (also called structural posts). Step 15. If you install the post the same day as you poured the concrete, the footing could crack. They are also less … "there should be no more than 2m between posts holding up the frame but 4m can be allowed between ends of the frame providing the joists are no more than 450mm apart. Decking screws will have a clear shank at the top - which should be the depth of the deck board of choice. If necessary, adjust number of deck boards to match in both calculations, and see if different board gaps at each end of deck are acceptable, compared to equal gaps and cutting the last board at an angle. Deck Design Software. Measure the distance between the two hardware pieces, then subtract 1/16 inch or so to account for imperfect cuts. For our design, we want to use 4 x 4 posts cemented every 8 feet and run them up through the deck to be used as the rail posts. My question is, how many posts do I need in the ground for this deck to be sturdy. I hope this is making since! COVID-19 Update to Customers ... At the other end of the bearer, place a support post on a flat, hard surface. Some builders position them every 4 feet for a completely rigid frame. The calculations below list approximate recommended deck beam spans. If necessary, adjust number of deck boards to match in both calculations, and see if different board gaps at each end of deck are acceptable, compared to equal gaps and cutting the last board at an angle. This ensures that the deckboard its tightened down onto the joist with the actual screw thread doing the work in the joist. This is good if you are looking to save a few dollars; however, code will not allow you to space your deck posts as far apart beneath your beam when using 4x4s. There are two approaches to designing a deck and selecting the right-size components, such as correctly sized deck posts. The outside run of stumps will need to align with the outside edge of the deck. Use a hand sledge to tap the 6x6 into place, check for plumb, and drive nails into all the hardware holes to secure the post. He also shows how with a little additional detailing work, his deck support posts reflect his pride in craftsmanship. Terms of use. Add gravel and smooth as you go. A shorter beam span means more deck support posts. If you're unsure ask for assistance in store, and make sure you bring your deck plan with you. Step 14. But decks 2 feet or higher will need added support. Just follow the instructions below and once you know how many boards you need, nip over to our online shop to see our complete range of decking boards. Beams made of two or more pieces are usually at least as strong as solid beams of the same size. Many deck screws will not have the thread size listed, as the term “deck” usually indicates a coarser thread. Here is a list of some common joist sizes and maximum “spans”. A span is the unsupported distance between two posts. If you're building a simple deck, footings and posts should be placed less than 8 feet apart. A “cantilever” is the unsupported end of a joist that extends … Think of detached decks like an island in your large kitchen. Step 3. 2. Many people use natural wood timber for their decking frames. Divide the area of your deck by the area covered by one pack to see how many packs to buy. Deck post size is important. Allow at least two days for the concrete to cure before drilling holes and installing a post. For instance, a beam made of two 2x8s is probably stronger than a solid piece of 4x8. Take any off-cuts to the tip. Use a hand sledge to tap the 6x6 into place, check for plumb, and drive nails into all the hardware holes to secure the post. This video shows how to install decking posts for an elevated deck. That makes a total of eight posts that need to be installed on this average size deck. You can try to drill holes in concrete with a standard 3/8-inch drill, but it will be very slow going. Drill a hole of the recommended size, a half inch or so deeper than the sleeve anchor. But these can bow seriously, even if a deck is only 3 feet off the ground. When using the word “coarse” to describe thread size, this only means that the threads are further apart than what would be found on, say, a machine screw. Of course, the latter will cost more. Reposition the post base, aligned with the layout lines, and tap a sleeve anchor down into the hole. So build your deck the right way, from the ground and posts up. Finish your decking posts with post caps or ball tops. This video shows how to install decking posts for an elevated deck. According to building codes, there is no clear answer on when you should install a 4×4 vs. 6×6 deck post. Position the post base as shown with its inside area aligned with the pencil lines. The answer depends on the size and shape of your deck, the size of your footings, and the size of your beams. Save yourself time and energy by using a standard-voltage heavy-duty hammer drill like this one, which will bore down with ease. In general, posts should be spaced no more than 8 feet apart. So in this article, we’re exploring how to safely put a hot tub on an existing deck. If you are using a centre spacing of 1m for your posts, you can then use this simple calculation to determine how many posts you’ll need to buy – 1 + Decking Width (Metres) + Decking Length (Metres) + Total Sqm = Total No. Cutting and Detailing Deck Support Posts Brendan Casey, Casey Fence and Deck – Frederick, MD. If setting timber post straight into the ground you may wish to coat the timber that comes in contact with the ground with some type preservative. Pull out most of the dust by lifting the drill bit quickly as you drill, two or more times. Or, if your deck has many angles, additional footings are necessary. However, if you’d like your deck farther out where there’s more space, you can install a detached deck. Top Tip. However, experienced contractors will tell you that a 4×4 post simply can’t carry the heavy load that many porches require. How to Slope a Deck for Water Runoff and Drainage, How to Attach Deck Post Bases to Concrete Footers, How to Connect a Notched Wood Post to a Beam, How to Install Concrete Support Deck Posts & Columns, How to Install Deck Post Wraps and Sleeves, How to Use Shared Load Deck Support Posts, How to Use Steel Metal Deck Support Posts and Columns. Also, a home’s electrical panel must be at least 10 feet above any deck structure or at least three feet to either side of it. If your deck is slightly out of square (different widths), calculate results for both widths, and set out each end to suit. The maximum distance between footings is determined by the size of your joist material. Parting boards, also known as pattern boards, add a distinctive look and can eliminate the need to butt boards together to span the width of the deck. Many screws for decking will have ridges on the bottom of the head, which helps the screw to counter sink without too much effort. My Account. Find the number of posts by measuring the running linear feet and dividing by 8 feet plus 1 for the end, plus 1 more post for the steps, totaling 8. The Jacksons decking calculator tool will help you get all the pieces and specifications together to create your garden decking plan - give it a try today. The larger the beam and footing size, the fewer footings that are required. While a typical deck under 6 feet in height may only require posts set every 5 to 8 feet, the type of deck, the type of wood, the height of the deck and a variety of other factors can influence the spacing of the … I am going to be building a deck around a pool this spring. With the posts in place, you can remove the temporary supports. And if a deck is over 10 feet tall, you should install bracing. Use a level to mark the post’s corners, then use a square or straightedge to mark its outline. The 17' is on each side of the pool and will circle out, at the middle of the deck the length of the deck will be 13'. Most detached decks are built at ground level, but some homeowners do go the extra mile and install raised, freestanding decks. The decking posts need to be spaced at every metre in each direction. Add a gate to keep young children and pets safe in one place. Install the bracing every 16 inches. The added support posts should be no more than 30″ apart & ideally placed in poured concrete. The support post’s side should be flush with the outside of the beam or doubled header. If using stirrups allow for at least a 75mm clearance between the ground and the bottom of the post. Read our Buyer's guide to decking. Work out how many posts and rails you need. Our nifty decking calculator is just the job if you’re having trouble working out how many decking boards you need for your next project. More info on fitting posts here- http://www.ultimatehandyman.co.uk/diy/decking/fitting_decking_posts.htmNormally on a hole of this size I would normally throw in at least one bag of gravel, but didn't have any at hand. Lengths of posts , postmix and fixings are added Decking: The decking is supplied in the lengths that suit your job , these are calculated as covering 150mm (145mm for the board and 5mm gap for expansion and contraction) , any decks over the 5.4m long that are required are given in 4.8m lengths so there is as little joins as possible. This meant using more postcrete than I would do normally! Install bracing cut from the same 2 x material you used for the joists — 2 x 8 for this deck — between joists in the middle of the frame to support parting boards. Don't burn your wood off-cuts as timber treated with preservatives can give off harmful fumes. When evaluating the costs of garden deck installation, there are various things you need to consider. Use a crescent wrench or a socket wrench to tighten the nut, which will cause the anchor’s sleeve to expand so that it grips the concrete firmly. That means that once you have the footings in place you need to install posts - which will support the beams - that in turn support the joists – that support the decking – and eventually you, your family and friends. Making sure the bearer is level, mark its height on the support post. Scribe a circle where the base’s lag screw will go. In some places you need permission to build an elevated deck, some decks also require planning permission and need to be built in accordance with your local building code, so please check with your local building control office etc. Copyright © 2021 Trex Company, Inc. All rights reserved. The calculations below list approximate recommended deck beam must span—that is, how many posts you 'll need hard! Feet off the ground timber for their decking frames beam spans meant more. 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