Browse Forums Outdoor Living 1 Jan 03, 2016 5:37 pm Hi all, I am planning to take on the mammoth project of building a deck this holidays. I must admit up front that I am a novice DIYer and am really stepping it up a notch with building a deck. I also apologise if these questions have already been answered. I did do a site search as per the forum recommendations though could not find specific answers. Proposed Deck specs: - composite decking (ekodeck in a sort-of herringbone pattern) - attached to ledger which will be fixed to concrete slab of a reecently built brick-veneer house (I still need to check that it is concrete behind the tiling exterior to the rear sliding glass doors) - 3500 x 6800mm (6800 side attached to the house) - should meet exempt development requirements as per the blacktown council regulations Questions: I am getting a steel pergola installed (via 'Amazing Home Improvements') with posts (90x90mm) at each corner of my proposed 3500x6800mm rectangle. Can I fix a bearer directly to these pergola posts? If so, my research suggests that a timber bearer is unlikely to span this distance (6800mm), would I be best to use a steel joist or add an extra footing? Can I then attach the joists from the ledger directly to the pergola posts and bearer (which is fixed to the posts)? Would I need additional footings anywhere else under this structure? Also, please let me know anything I have not considered or will need to consider. I don't go into projects without researching as much as I can but sometimes there is just things I don't even think about. Thanks for your help! Daniel Re: Novice deck planning 2Jan 08, 2016 10:34 am dkun0457 I am getting a steel pergola installed (via 'Amazing Home Improvements') with posts (90x90mm) at each corner of my proposed 3500x6800mm rectangle. Can I fix a bearer directly to these pergola posts? Technically yes. The footings of the posts if done properly should be sufficient to support the bearer. Albeit a.) you'd need to attach the bearers after the inspector has signed off everything and b.) you don't need a permit for the decking. You might void warranties on any issues of the pergola due to structural integrity which will need to be kept in mind. dkun0457 If so, my research suggests that a timber bearer is unlikely to span this distance (6800mm), would I be best to use a steel joist or add an extra footing? You'd need something really magical to support a deck with a 6800mm beam span. Also, your pergola footings would then definitely not be able to support the intended footprint. It is not uncommon to have footings for bearers every 1200mm to 2400mm (depending on the depth of your timber/steel bearer so you'd only be avoiding the digging of 2 footings in your equation). dkun0457 Can I then attach the joists from the ledger directly to the pergola posts and bearer (which is fixed to the posts)?Daniel You'd need a bearer in between the house and the pergola. Maybe two. dkun0457 Would I need additional footings anywhere else under this structure? Yes!!! You'd be looking at potentially digging 15-25 footings to support a deck of that size. All depends of course on the depth of your bearers, joists and how much room you have from the top of your deck to the ground. dkun0457 Also, please let me know anything I have not considered or will need to consider. I don't go into projects without researching as much as I can but sometimes there is just things I don't even think about. Best to draw up your plans and post the diagram. Also, the mod wood does not like butt joins as you are required by the manufacturer to leave a gap of 5mm due to expansion/shrinking. As I am assuming you will have the decking going pergola post to post and the max length of mod wood these days is 5400mm, you'll have a join in there somewhere. Also, mod wood required 350mm joist centers rather than the conventional wood decking which is 400mm-450mm. Another one, depending on your desire to clean the decking, choose a darker colour for less frequent cleaning. Refer to the Ekodeck website for "Cleaning Chart". Re: Novice deck planning 3Jan 08, 2016 8:56 pm Thanks for your guidance Adam. I'm very glad I asked these questions before starting! I didn't think of voiding the warranty by attaching the deck to the posts. Great tip! I'm going to mark it all out with builders line tomorrow so I will post a detailed plan and some pictures on Sunday. The reason I ask so many questions about the footings is that I see this to be one of the messiest parts of the project. Wood I am fine with. Concrete, and particularly having to pour it around stirrups that need to be in an exact location, exact height and plumb, is a bit daunting. And I'll have to do 15-25!! Any tips in this area? Lastly, you mention 5mm butt joins. How does this look when I am screwing the boards 20mm from the end? Would I need two joists? Or could both end screw into one joist? Thanks again, you have given me a lot to consider. Re: Novice deck planning 4Jan 09, 2016 2:57 pm Okay so i have spent all morning doing some drawings on Microsoft Paint. Sorry if they are not very good quality but they should give a good impression of my plan. I also took some photos of the area with the deck level marked out with builders line. Site photos https://www.imageshack.us/i/p72ALXuuj https://www.imageshack.us/i/hlgglDUdj Top view drawing showing joists/bearers without decking https://www.imageshack.us/i/p7k6dcGrj Top View drawing with decking on top. I did not draw all the individual boards. Just a regular horizontal pattern. https://www.imageshack.us/i/p3EdCjSJj Side view drawing https://www.imageshack.us/i/p3bcEu3Zj Front view drawing https://www.imageshack.us/i/p7uk4lTFj In the top view drawing I spaced the joists 450mm as the ekodeck website installation instructions said that 450mm was okay. What do you think? Installation guide can be downloaded here http://www.ekologix.com.au/ekodeck/deck ... tallation/ Look forward to hearing yours and other peoples feedback. Thanks Re: Novice deck planning 5Jan 11, 2016 11:17 am dkun0457 I didn't think of voiding the warranty by attaching the deck to the posts. Great tip! As a side note... It’s only two holes but I would insist to see the holes once they are dug to confirm they are against the spec. I am not sure what they are but I am guessing they would have to be greater than 300diam by 600deep. dkun0457 The reason I ask so many questions about the footings is that I see this to be one of the messiest parts of the project. Wood I am fine with. Concrete, and particularly having to pour it around stirrups that need to be in an exact location, exact height and plumb, is a bit daunting. And I'll have to do 15-25!! Any tips in this area? Like “The 5 Stages of grief”, so goes “The 5 Stage of drawing your deck plans”. Step 1… “Denial” that you have to dig so many holes. Step 2… “Anger” that it can’t be done any other way. Step 3… “Bargaining” that you could increase the bearer widths Step 4… “Depression” that you will have to dig so many holes. Step 5 “Acceptance” that you just need to pucker up and do it. Why do I know these stages?? Because I went through it when I built my first deck. First, get yourself a $120 laser level. Best thing under the sun and you’ll be using it more than often for other projects. Then you dig your holes, screw the bearers to your stirrups, sit them in and brace the whole lot so it doesn’t move. Carefully pour the holes and adjust accordingly. Or, pour your holes with concrete and level off flat. Use adjustable stirrups that sit on a flat surface and use a bit of 90x90 timber to attach the stirrup to the post. With 1 ledger and 2 bearers, you’d need 4 supports per bearer minus the two at the ends. So only 10 holes. I checked against AS 1684 and all will comply with 140mm deep joists and bearers. dkun0457 Lastly, you mention 5mm butt joins. How does this look when I am screwing the boards 20mm from the end? Would I need two joists? Or could both end screw into one joist? I’m guessing you are going to use the offcut of the last length to make up the difference of the next length? Eg. Like a traditional way of laying a deck rather than have all the boards nicely side by side and include a middle board? By the way, nice work on the plans. Re: Novice deck planning 6Jan 11, 2016 1:12 pm when you say "herringbone" are you doing one or multiple lines of the pattern? in any case you will need to add blocking to your frame for fastening the boards. More lines, more blocking and potentially more wastage. could be expensive. also ive seen adjustable stirrups somewhere, might be worth looking into to make the job easier. Creator of superduperonium, expert at expert things, nobel laureate, can hold my breath for 10 minutes. Re: Novice deck planning 7Jan 11, 2016 7:45 pm Thanks again Adam! I think I have already reached the acceptance stage haha Now for a few more questions: - have you had any experience with cardboard tubes for making concrete footings? I am thinking of going your second option for making footings and these tubes look like an error free way of making level footings. - I don't quite understand your 10 footings. I can understand four under each bearer, that's what I put in the drawings, but what do you mean by the 'two at the ends'. - how deep would you dig your footings? Does it depend on when you hit solid ground/clay? In that case it would be like 150mm for me. - I am definitely planning to use the offcuts to make up the difference, my question was more to do with the inevitable but joints. I have to screw down the decking screws 20mm from the end of each board and you say 5mm between board ends. This would make 45mm between screws at a butt joint. Is that not the width of a joist? Do I just angle the screws to grab the joist or put two joists next to each other? - last question, how would you transport 5.4m lengths of decking from store to home?? I only have a RAV4! I know it's a silly question but I just need confirmation that I need to hire a truck or ute or something? Thanks Adam! Ponzu - I have given up the idea of herringbone as it appears to be too costly and complex. Just a simple horizontal design for me. Re: Novice deck planning 8Jan 11, 2016 10:45 pm dkun0457 - have you had any experience with cardboard tubes for making concrete footings? I am thinking of going your second option for making footings and these tubes look like an error free way of making level footings. Good to hear you are in "acceptance stage"! Cardboard tubes are only required for sandy situations where there is a risk of the hole collapsing. You have a decent amount of time to level off the concrete and you wouldn't need any more than a small spirit level and a trowel. It doesn't have to be absolute dead straight. Just make sure you will have enough space to fit the small post you will chuck in there or make the top of the footing almost right underneath your bearer so all you will need to do is to bolt the bearer direct to the adjustable stirrup. dkun0457 - I don't quite understand your 10 footings. I can understand four under each bearer, that's what I put in the drawings, but what do you mean by the 'two at the ends'. That's my mistake. You will have 1 ledger and two bearers. 4 supports under each bearer and the bearer furthest from the wall will have each end attached to the verandah posts which means you only have to dig 4 + 2 =6 holes. That's if you are attaching it to the verandah still. dkun0457 - how deep would you dig your footings? Does it depend on when you hit solid ground/clay? In that case it would be like 150mm for me. dkun0457 - I am definitely planning to use the offcuts to make up the difference, my question was more to do with the inevitable but joints. I have to screw down the decking screws 20mm from the end of each board and you say 5mm between board ends. This would make 45mm between screws at a butt joint. Is that not the width of a joist? Do I just angle the screws to grab the joist or put two joists next to each other? If I read the installation guide right, 20mm is from the edges of the board and 15mm is the min spacing between the end of the board at the fastener. The 5mm I am stating is the gap you need to leave between two boards butting each other. Yes the biggest detractors of mod wood. I have seen the gaps filled with same coloured silicone to cover it up. You'd have to ask yourself if it's a deal breaker. A good practice when screwing a butt join is to angle the screw into the middle of the joist by a few degrees to ensure you get a good grip. dkun0457 - last question, how would you transport 5.4m lengths of decking from store to home?? I only have a RAV4! I know it's a silly question but I just need confirmation that I need to hire a truck or ute or something? Your easiest bet is to go to Masters (if you have one close) and hire their ute for a daily rate +100km for $65. It'll be cheaper than most methods. Noone is going to pull you up for driving a masters ute into a Bunnings Yard. I have done it heaps of time. No such thing as a silly question... all questions lead to enlightenment - Dr Karl Give Jonathan a call. Tell him you know me. He is in my opinion the best surveyor I have ever worked with. His number is 0425 285 622 All the best Simeon 3 12420 I am not based in Victoria however i had a quick look into your question to understand what you were asking. The way I read the regulations, overshadowing relates to the… 1 2239 "is it exempt or do I need to get permission from council" Call your Council and ask them 1 1579 |