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Blu_Rock
11th March 2008, 11:35 PM
I have been reading this forum for several years now and thought that I would share my deck/pergola building experience with anyone who is interesting in reading. This is my first posting on this forum so I hope it is of some use to those who are considering constructing their own deck. I stated building it in early December 2007 and am still going strong and am about 2/3 the way through. I have a slight (obsessive) tendency to over-engineer things but at least I know that it probably will not fall over in my lifetime.

I had been thinking about the design of a deck for the rear of my house for several years and I had a basic idea of what I wanted. As I wanted to have easy trailer access to the rear garden, the deck would need to have an angled side beside the drive to allow clearance for the trailer to fit between the existing garage and the deck. Seeing as I had one angled side, I tossed up a couple of design ideas that would make the overall structure more interesting (and difficult to construct, as I like a challenge) and settled on an octagonal protuberance as a feature. The deck was to be about 28 sq mtrs, have two sets of stairs and a pergola covering about half the deck. The rough plan below is not to scale.

Before construction began, I decided that a man can never have too many power tools and I shelled out for a 255mm Makita LS1040 compound mitre saw (http://www.makita.com.au/product.asp?ContentID=ls1040) that I picked up on special for $330. Given the disturbing number of odd angles that my creation was to need, that was money well spent and I highly recommend this fine piece of equipment. It is built like all Makita stuff (made to last), consistently cuts the same angle and is a joy to use. A couple of months previously, I had bought a 14v Makita cordless drill and it too is a great piece of machinery and is a considerable improvement on the POS Ryobi 12v that I initially bought (will not maintain its charge over night and, even when fully charged, is gutless… what was I thinking when I wasted my money on that rubbish?).

I read up on deck construction on this forum and quickly discovered that I needed to get a hold of Alan Staines’ book Deck and Pergola Construction Manual “the Bible”. It is The definitive reference book and threw light on numerous finer points of deck construction that are essential for the uninitiated. After a fair bit of forum combing and deliberation, I opted for a treated pine structure with merbau decking and handrail.

Consulting Staines' span tables, I decided on using two by 90x45 for the bearers and 90x45 for the joists. I hired a posthole digger (the sort that uses a triangular frame rather than the widow-maker that requires two people to operate) and sunk the holes for the foundations. I planned on using F7 treated pine so there were about 20 odd footings to be dug. My block is on terrible reactive clay soil so I decided to go down 600mm and unfortunately I hit 4 pipes, 1 stormwater that I pierced in two places, 1 stormwater and 1 wastewater that I hit but did not break. Off to Bunnings (again) and got a PVC joiner, a mtr of PVC pipe and a rubber pipe joiner to fix the damage. From this experience, I would say only go down 600mm if the post footing sizes tables indicate that you absolutely need to go down that far, at 450mm I would had cleared the pipes.

I had got a hold of a cheap S/H cement mixer (almost new for $200) and began mixing the concrete for the foundations (it took a lot of concrete to fill those holes). I used stirrups to support the posts and held them in place while the concrete was setting by lightly screwing them to lengths of 90x90 treated pine that I had laid out. Not the usual way to do this but it worked. Concreting in the stirrups for the octagonal feature was a bit of a nightmare and I must have used every G-clamp at my disposal to get everything in the right place. After all the footings were in, I laid down weed mat and river pebbles to control weeds that may decide to grow under the deck.

Initially, before doing the research, I was going to use a ledger strip to attach the deck to my brick-veneer house but the code states that, generally, brick veneer walls are not to be used as load bearing structures for decks etc and therefore I would need another row of bloody footings.

Unfortunately, when I went to buy the 90x45 pine, the supply of F7 had all but dried up (at least in Canberra). Luckily, at the time of setting out the footings, I had over-engineered the number of footings and put them closer together than the span tables had indicated for a F7 structure. They were sufficiently close together to be suitable for the F5. Otherwise, I would have needed to up the bearer & joist specs. In the end, I did manage to get some F7 but about half of the bearers & joists are F5.

After using the water-in-a-clear-tube levelling method to mark off the stumps (90x90 treated pine for the central stumps and 90x90 merbau posts for the perimeter hand rail posts), I cut the stumps to length and circular sawed/chiselled out the numerous mortises for the bearer housings. I used 2x10mm coach bolts to secure the bearers to the stumps and posts and Pryda triplegrips to secure the joists to the bearers. The whole lot was braced in numerous places to ensure all was sound. I sealed all of the cut ands and joints with a couple of coats of Solarguard.

To be continued

brynk
12th March 2008, 09:25 PM
welcome!

it is an interesting design & i look forward to seeing your structure and floor-board finish for the "turret". (hey it's not that bad - i'm feeling uninspired - but i know you know what i'm talkin about:roll:)

r's brynk

Blu_Rock
13th March 2008, 08:23 AM
Brynk, thanks for the welcome:U

I was initially thinking of doing something fancy with the deck board layout for the turrent, but I have decided to go with a simple layout with its boards parallel with the the deck's other boards.

Half of the deck is going to be covered by a pergola that, in the long run, will be covered with laserlight. Staines provides a great deal of detail on how to go about attaching a pergola to a house’s fascia and as this was one area that I was uncertain about, I found this section of his book invaluable.

My house has metal fascias and the method that I selected to attach to this type of construction involved screwing 140x45mm noggings between the ends of the roof trusses using metal framing anchors. I then used 75mm, #14, type 17 roof batten screws to attach an external ledger to the noggings. The whole thing is pretty solid

From my searches of the Internet and this forum, it appears that the pergola’s roof requires a minimum of 5 degrees fall to have adequate drainage or whatever and as I suspected that head clearance between the finished deck height and the pergola’s beam (190x45mm F7 treated pine) may be a problem if too much fall was given, I went for the minimum amount of fall. As it turned out, at 180cm (about 6’ for you old timers) the top of my head has about 6” (150mm) clearance. The rafters are secured to the fascia ledger with hangers, and to the beam with non-obtrusive L-shaped gal brackets. I painted all the pergola timber, including the battens with a couple of coats of Solarguard (Manor Red) and screwed the rafters to the brackets with gal 8g 30mm button wafer screws and for the battens I used 120mm, #14, type 17 roof batten screws. There are a couple of oddly-cut rafters where the pergola’s roof tapers down in width and these took a while to shape to ensure a good joint

Regarding using treated pine for structural timber, I have never had to work with such dimensionally unstable timber in all my born days and it was a constant challenge to get everything more-or-less square and true. This stuff is really appalling and in my experience, unless you secure it down as soon as you get it, most of it will end up looking bloody banana shaped in short order. The first load of 90x45s that I got was initially all pretty straight as it was fresh out of the pack but that soon changed, even though I stored it on level ground and undercover. Some of it ended up so badly twisted and bent it was only good for bracing. The next load I got from Bunnings was all F7 that I used for the floor joists. I hand picked only straight lengths and had it all nailed down the following day. The joists have remained fairly straight even thought I have not laid the decking as yet.

brynk
13th March 2008, 09:34 AM
Regarding using treated pine for structural timber, I have never had to work with such dimensionally unstable timber in all my born days and it was a constant challenge to get everything more-or-less square and true...

:U ... and then thinking about my own experiences, :~

same with the mgp & finger-jointed battening .

Chumley
13th March 2008, 11:30 AM
Hi Blu-Rock,

Great thread and good looking project. I've had similar problems with treated pine going artistic on me. I just finished a gazebo that I started in June last year (still have to post the last set of pics), so don't worry about the slow build - enjoy it.

Keep the thread going - it looks interesting.

Cheers,
Adam

Blu_Rock
14th March 2008, 07:24 PM
Thanks Chumley.

I wanted to have a fairly chunky-looking handrail and I used 90x42 merbau for the job. For the rails that join the posts squarely, I used stop end housing joints. I used a router and a simple jig that I made to route out most of the material and then finished off the job with a sharp 35mm chisel. Joining the rails to the posts at the octagonal feature was a little more complicated and required a bit of planning to get a nice finish. These joints could be best described as angled dado joints. The housing tapers down from about 40mm deep to flush. I used a tenon saw and chisel to make these and they came up pretty well. As could be expected, the last one that I did was a much neater job than the first.

The cross section of the handrail is T-shaped and I routed out a shallow recess in the bottom of the top rail to ensure that the bottom rail would not bow over time (either inwards or outwards) and also the recess ensures that you will not be able to see a gap between the two pieces. Initially, the bottom piece was the full 90mm width, but that looked all together too chunky and so I ripped it down to 65mm.

I screwed the two pieces together with 3 x gal 75mm, #14, type 17 roof batten screws. Prior to making the deck, I had not previously used this type of screw (they are self counter sinking and have a hex drive to screw them in) and they are excellent. I used them in numerous other places when making the deck and even though they are probably a little expensive, they are just too convenient.

To secure the rails to the posts, I used gal screws that are screwed in from underneath the top rail. I countersunk them and it all turned out fairly neat and tidy. Prior to assembly, I routed the edges of the top rail with a rounding over bit. In the photo below you can see, on the LHS of the second rail along, where the router bit made a deeper than planned cut into rail when the bearing on the bottom of the bit fell to pieces. I thought I would tidy up the damage and install the rail regardless to serve as a reminder that cheap router bits (I think I paid about $25 for a set of 15 bits) are not made to last.

I am still tossing up whether or not to cough up the $500 or so to run 3 S/S balustrade wires between the posts. As the deck is only about 700mm off the ground there is no planning requirement to have balustrades but they look cool. I will decide about that later on. I have already checked with numerous suppliers (local, online, eBay and via recommendation from Loki's deck thread (http://www.woodworkforums.ubeaut.com.au/showthread.php?t=59049&page=3)) and Loki is on the money as Miami Stainless (http://www.steel-fittings.com/balustrade_methods/basic_balustrade_methods.htm) in Burleigh Heads QLD came up the cheapest for what I am looking for (minimalist) and they appear to have a superior product (Streamline Threaded Insert/Swage Stud Method).

I found merbau to be a nice timber to work with (apart from the bleeding tannins) and it cuts/works easily and cleanly. The finish that I ended up applying to the handrail (and will also go on the deck) was Flood’s Spa-N-Deck cedar colour. This decision was not made lightly and I agonised over whether to use and oil-based stain or an alternative. The advice previously given by others on this forum convinced me that Spa-N-Deck (http://www.floodaustralia.net/products/spandeck.htm) was the way to go, mainly due to its longevity. This thread (http://www.woodworkforums.com/showthread.php?t=60747) has a decent discussion on the pros and cons of different decking finishes but there are many other threads where the issue of deck finishes is discussed.

Bunnings sells Spa-N-Deck but I bought it considerably cheaper from Bristol.

Blu_Rock
30th March 2008, 06:55 PM
Today, I finished off the first set of stairs that lead down to the garden. As you can see from the photos, they are fairly solidly built and they have taken more time to build than I had initially thought… but doesn’t everything. They are held up with four stirrups concreted into footings. They are also bolted onto the deck at the rear. The rise is 180mm, the going 350mm and they are about 1.4m wide. In the end, I decided to go with stainless steel decking screws, but more about that in another post.

There is a short handrail that bolts onto the side of the stairs and you can see one of the bolts hanging out in the second last photo. It matches the rest of the hand railing and its upper end attaches to one of the pergola’s posts via a joint that took me some time to figure out and cut. The compound saw has again proved invaluable for cutting difficult joints like this. I will paint the exposed timber in the joint before final assembly.

I have another set of stairs to build for the other side of the deck and they will lead to the drive. But for now, I have had enough and next weekend it will be back to laying the deck boards and hopefully, I will get them finished off.

tim120977
31st March 2008, 11:39 AM
Hi Blu Rock,

I'm in the process of planning a deck at home and was looking at using 2 by 90mm by 45mm bearers like you did. I was just wondering if you could let me know what stump spacings, joist and bearer spans that you used? I was planning on using F7 TP but like yourself i'm having problems sourcing it so it will be F5 for me i think.

Cheers!

Blu_Rock
31st March 2008, 07:52 PM
Tim

This post (http://www.woodworkforums.com/showthread.php?p=700601#post700601) has a link to download a PDF that has joist span tables that cover F5 seasoned softwood. It shows 1300 for continuous spans and 1100 for single spans (I have 1300 joist spans at 450mm centres).

As far as the bearer spans are concerned, I used 1200 spans (continuous span) and the deck has no bounce, so I suppose all is well. In my case the load width is 1300.

This link (http://www.chhwoodproducts.com.au/userfiles/5/File/588.pdf) has F5 bearer span tables (table 3) and for 2/90x45 with a 1200 load width it has a maximum 1700 continuous and single span. If you need more comprehensive F5 span tables, then I suggest that you start a new thread asking if anyone has the tables covering F5 timber.

Good luck with the build.

tim120977
1st April 2008, 09:59 AM
Thanks Blu Rock,

That was exactly what i needed. I have already decided exactly what size my deck will be so i just have to work around that. At this stage i will have 2 90mm by 45mm F5 bearers will span 1300mm continous and the 90mm by 45mm F5 joist will span 1150mm continous @ 450mm centers. So hopefully it wont hve too much spring! The deck will be about 45m2 and It looks like i will have around 44 stumps which sounds like lot but i have a lot of long steps and mutible levels on this design. I will start a thread soon with some plans and progress pics.

Thanks again Blu Rock!

Tim.

Blu_Rock
1st April 2008, 07:29 PM
Tim, you are welcome. With those spans, the deck will be solid and wont bounce. 44 stumps is a lot of bearer housings to notch out. I look forward to seeing your pics.

Bloss
4th April 2008, 11:50 AM
Regarding using treated pine for structural timber, I have never had to work with such dimensionally unstable timber in all my born days and it was a constant challenge to get everything more-or-less square and true.

You must have got the stuff I leave after hand picking at the supplier! http://www.woodworkforums.com/images/smilies/happy/biggrin.gif

After years of sorting at the site and then taking back timber to my suppliers that was simply too twisted and deformed to use I almost always now take the time to select my own at the suppliers premises. I reckon I choose maybe one in three sticks - sometime there is reasonable batch, but mostly it is pretty poor.

I assume those I reject are sold to someone else when in fact they should be sold as seconds or thirds. Radiata pine is always problematic and has become worse since they now harvest at 18-25 years when it used to be at 30-35years. The treatment doesn't help given it is a wet process, but you should demand dimensionally stable structural timber.

You should always take back to your supplier any pieces that were unusable and get a full refund - they often have to be a minimum of 1.8m and they often will refund only to the nearest 300mm, but you should not accept poor goods that are unfit for your intended use purpose.

BTW - Love your deck - great bit of work!

Blu_Rock
4th April 2008, 10:00 PM
Bloss, I agree about hand selecting the timber. Since that first load, I have gone and hand select the timber. Depending on when you go, the good:bad ratio concerning relatively straight treated pine in the yard can vary from a good day 1:3 good:bad; to a bad day 1:6 or even worse.

I know that the yard will take back the lengths that are badly bowed/twisted but that is an inconvenience for me. That said, there are several lengths of the merbau decking (that came with the original load) that I will return for exchange as they are either badly bowed, twisted or wavy. As for the original load's deformed treated pine, I have been able to use that for bracing/shorter runs and therefore used it selectively.

In Canberra, there is a supplier that has a strict policy of ensuring the supply of straight treated pine but you pay a considerable preium for one of their employee's to go and hand select from the mill.

Blu_Rock
15th April 2008, 08:19 PM
I have been plugging slowly away at laying the 90mmx19mm merbau decking timber and it was a very slow process to begin with. From the word go I had decided to go with screws to fasten down the decking because I have had experience with nails pulling out of the joists on a smaller deck that I put down about 10 years ago. It only took a couple of years before the nail heads started to pop up proud. With this current build, I started the job with countersunk galvanised square drive screws 10g x 50mm @ $60 per 1,000. I screwed in about 200 screws and sheared off about 10 where the thread joined the shank. Removing the stubs that were left in the joists was a major pain in the a#se. I came back to the forum and read up on what type of fasteners to use and how to go about screwing the boards down. This thread (http://www.woodworkforums.com/showthread.php?t=66531) has an interesting discussion on the best type of fasteners to use and I was quickly convinced that I had to go with the stainless steel screw option. I know that most people recommend using 10g x 50mm type 17 non-trim head screws but my local specialty shop, Specialty Fasteners (http://www.specfast.com.au/), recommended 9g x 53mm type 17 trim head screws @ $149 per 1,000, so I went with them.

I decided that I wanted a sleek look and therefore I wanted the “end capping” (i.e. the planks that close off the crawl space under the deck) to sit flush with the upper side of the deck. This required that all of the planks be cut to the exact length before they were laid. I could have done it easier and had the upper lengths hanging over the side of the deck, or the ends of the planks flush with the sides of the deck, but that was not the look I was going for.

I am more than a bit anally retentive when it comes to ensuring that everything is true and I really wanted all the screws to be lined up in perfectly straight rows. To get this result, I used a string line to set up two small wooden blocks at either end of the joists and then it was a matter of cutting 4 runs of decking to length, laying them temporarily down on the joists, pushing them together so that they were all straight, laying a straight length of 25mm x 25mm aluminium between the blocks to use as a straight edge and then marking out lines for the screw centres. I then used a template made from a scrap of 3 ply to mark in 15mm from either side of each plank. A time consuming process but the end result was worth the extra effort.

After reading this thread (http://www.woodworkforums.com/showthread.php?t=69126), I was going to buy a Carb-i-Tool to do the drilling and countersinking but ended up going with a much cheaper Snappy brand American-made 1/8" bit that Specialty Fasteners also sold for $15. I have put in about 2,000 screws with this baby and it is still going strong. I saw those so-called smart tool drill/countersink bits on eBay or somewhere but they look like a bit of a gimmick. That said, it is probably OK for beginners who have difficulty judging how far to countersink using a more conventional bit.

I then pre-drilled all the holes for those 4 boards, cleaned the swarf off the joists and then started to lay each plank using clouts as 3mm spacers between the planks. Some of the planks were either sitting up from the joists or were bowed so I used sliding G clamps to pull those boards down flush and parallel with the previous run. While laying the planks, I constantly checked that they were maintaining right angles to the wall that I was working off (by measuring to a line that I had marked off across the joists). This required a slight adjustment to the spacing between the planks every so often. I used a cordless drill to drive in the screws and had not problems with the stainless screws shearing off.

I did no want to end up ripping down last plank too skinny to fit the space left, so when it came to laying the last 10 or so planks, measured up the remaining space, made an allowance for the spaces between the planks and figured out how wide each would have to be. I ended up ripping down the last planks to 85mm wide and it all worked out nicely. Had I not done this, the last plank would have been about 40mm wide and looked out of place.

I am going to let the deck weather for a few months while I take care of the other set of stairs, enclose off the crawl space with dcking timber, make 2 sets of gates and a screen.

Williamstown
23rd April 2008, 11:45 PM
What is the purple/dark red paint, is it protection of some description?

Yonnee
24th April 2008, 12:49 AM
Mate, what an awesome job! Top stuff.:2tsup:

I'd like to challange the "world's slowest" though. I dug and poured the footings for my deck & pergola at the same time I did my shed footings...


...that was March '04. The pergola roof went on October '07 along with the green tongue floor base, and the tiles turned up last week. Just bought the first lot of cement sheet underlay tonight, with still more to buy.

Maybe by Christmas '08...

Blu_Rock
24th April 2008, 08:39 AM
Williamstown, the red/purple is the finish coat of Solarguard, Manor Red colour, that I have applied to all the treated pine timber. In real life, it's more of a reddy/brown colour.

Thanks Yonnee. I take your point, you are the man! I suppose that I named the post as I did because my mates are always asking why I haven't I finished the deck yet. They are used to tradesmen knocking up a deck in a couple of days or so.

ComboSquare
29th April 2008, 12:34 AM
The rise is 180mm, the going 350mm

Your stairs look good, however the formula for stairs is twice the riser plus the going should equal between 585 - 625mm (this can vary a bit, i've seen 600-625), your numbers = 710?

Blu_Rock
29th April 2008, 09:22 AM
ComboSquare, yes my stairs do not conform to the formula (I was aware of this during construction) but they are comfortable to climb. The stairs on my front porch are the same dimensions and my guests and I have had no problems with them. Thanks for the comment... good to see you are paying attention:)

UteMad
1st May 2008, 09:28 PM
Your stairs look good, however the formula for stairs is twice the riser plus the going should equal between 585 - 625mm (this can vary a bit, i've seen 600-625), your numbers = 710?


You sure on that one? 2R + G = 550 to 700

we build the deck stairs that are closed like yours with a riser of 170 - 190 and a tread of generally 4 boards (360mm ) as you have no nosing and considering they are usually quite wide with no handrail people dont slow down and miss the top step if its only 3 boards... we also go out to 5 and 6 boards if people want to use them a lot for seats

cheers utemad

tim120977
2nd May 2008, 10:00 AM
Hi UteMad,

I have just had my decking plans approved from the local council. Before they would approve it they wanted some additional information eg step riser heights and tread widths. Since I'm using 90mm by 19mm Merbau my riser height was going to be two boards =180mm plus 3-4mm for the spacing. Tread width 4 boards = 360mm + 10mm for spacing and top of the riser board + 19mm. = roughly 390mm. Then the council made me aware that there is max tread width of 355mm. This kinda screwed up my nice wide step idea. I know there is a min tread width of i think 260mm but i was unaware of the max limit. Has anyone else heard of this? Just after reding your last post UteMad you mentioned that you have used 6 to 8 boards for the tread. Is this using 90mm or 70mm?
Also a little bit off topic but my deck at the highest point is 650mm off the ground and i have 90mm by 90mm Merbau handrail post and wire balastrading basically just for looks. I had the wire spaced on the plan at 200mm spacings to reduce costs a little but the council have come back saying that i must have them spaced at max 100mm width and certain tensions etc. Is this accurate if the deck is not higher than 1mt???. Any information would be much appreciated!

Thanks

Tim.





You sure on that one? 2R + G = 550 to 700

we build the deck stairs that are closed like yours with a riser of 170 - 190 and a tread of generally 4 boards (360mm ) as you have no nosing and considering they are usually quite wide with no handrail people dont slow down and miss the top step if its only 3 boards... we also go out to 5 and 6 boards if people want to use them a lot for seats

cheers utemad

Blu_Rock
2nd May 2008, 08:14 PM
Like you, my deck is about 700mm off the ground so the hand rail is not necessary. I am considering adding 3 x S/S balustrade wires for ascetic reasons. However, because my deck size is less than a certain area (as well as a couple of other criteria), I don't need to get approval :) and therefore I don't know whether the wire spacing rule (in the ACT, the rule is no gaps wider than 125mm - and for wire, the deflection of adjacent wires should not be wider than 125mm?) would be called to bear. Maybe it's a case that if they are fitted, then they must conform to the spacing rule.

Also because of the deck's size, the stairs' dimensions won't be inspected, lucky me:D The reason that my steps are 4 boards wide is I also wanted the steps to be reasonable to sit on as well as comfortable to walk down.

I know that some specifications in different regional regulations are not the same. I'd visit your local planning authority/council and get a hold of the regulations (see them first hand) so you can check the validity of the council inspector's decision.

ComboSquare
2nd May 2008, 09:06 PM
You sure on that one? 2R + G = 550 to 700

we build the deck stairs that are closed like yours with a riser of 170 - 190 and a tread of generally 4 boards (360mm ) as you have no nosing and considering they are usually quite wide with no handrail people dont slow down and miss the top step if its only 3 boards... we also go out to 5 and 6 boards if people want to use them a lot for seats

cheers utemad


Interesting, I have 2 references that say twice the riser plus the going should equal between 585 - 625 mm. One reference is in 'The Australian Carpenter and Joiner' pg 541:
Riser = 115 min, 190 max
Going = 225 min, 395 max
2R + G = 585 min, 625 max

This is for external timber stairs.

Robo
5th May 2008, 02:19 PM
Your hand rail is made out of two pieces of wood. I've just made one around a balcony that has one piece of 95x45 like your top rail. Wide side of the wood sits horizontal, and is butted into the posts. In the longest section (about 2.5 m) there is a bit of flex. I'm worried that someone big might lean on it or worse still sit on it and it could break or pull away from the post. Do you think if I screwed another piece on its side underneath it would give it much strength? I don't think I'd be able to cut anything out of the post like I did for the rails now. So the new piece would be maybe 70 x 45 treated pine with 100mm gal bugle head screws into the bottom of the existing rail every 400mm or so.

One more thing, I painted the treated pine with an acrylic exterior low gloss finish that wasn't supposed to need any primer. Now the pine has cracked, particularly the tops of the posts. I thought of putting builders bog in the cracks and repainting it - any better ideas?

boban
5th May 2008, 05:29 PM
Interesting, I have 2 references that say twice the riser plus the going should equal between 585 - 625 mm. One reference is in 'The Australian Carpenter and Joiner' pg 541:
Riser = 115 min, 190 max
Going = 225 min, 395 max
2R + G = 585 min, 625 max

This is for external timber stairs.

Now I'm confused.

2(115) + 225 = 455
2(190) + 395 = 775

I haven't referenced any material, just looking at the maths.

Blu_Rock
5th May 2008, 08:34 PM
Do you think if I screwed another piece on its side underneath it would give it much strength?

Now the pine has cracked, particularly the tops of the posts. I thought of putting builders bog in the cracks and repainting it - any better ideas?

Either adding the extra piece or adding another vertical support half way along the top rail should stop the flex.

If the top is only butt joined to the sides of the posts then you have got a problem. Without a joint or suitable brackets you risk the top letting go and someone seriously injuring themselves. If this is the case, then one solution is to fix some "L" shaped brackets between the top rail and the posts with suitable gal screws. Then you can add the strengthening piece of timber and all should be OK.

Regarding the splits in the pine, that is the nature of treated pine and I am pretty sure that, to a point, you will continue to experience splitting of the ends, in particular. You can bog up the cracks and repaint but you are most likely going to have to redo this a number of times until the timber stabilises. Failing making some type of cap to protect the end grain, the bog & paint solution is the go.

Blu_Rock
5th May 2008, 09:12 PM
Now I'm confused.

2(115) + 225 = 455
2(190) + 395 = 775

I haven't referenced any material, just looking at the maths.

As ComboSquare notes:
Riser = 115 min, 190 max
Going = 225 min, 395 max

2R + G = 585 min, 625 max (different to Staines .. see below)

Re-arranging the equation, with a known riser
G = 625 - 2R (in the maximum case)
G = 585 - 2R (in the minimum case)

or with a known going
R = (625 - G)/2 (in the maximum case)
R = (585 - G)/2 in the minimum case)

Therefore if you went with the minimum riser height (i.e. 115) then your maximum going would be: G = 625 - (2x115) = 395

However, according to Staines pg 38 ...

"The going plus twice the riser should equal between 550-675mm, alternatively, the sum of 1 riser plus 1 tread should equal between 430mm and 460mm. Risers should not be greater than 190mm high and treads should not be less than 250mm wide."

He continues with some further guidance. I suggest you get hold of Allan Staines' book Decks and Pergolas Construction Manual.

These numbers serve as a guide, and depending on your council's regulations, approved structures will need to conform with the specifications in your region's regulations/code.

If all this is not clear, I suggest that you start a new thread so more people can see the question, respond with their comments and maybe make it clearer.. or not ... LOL.

namtrak
5th May 2008, 09:36 PM
Great thread, now that I've moved to Queanbeyan I should get you around to give me some serious design inspiration I need for a deck setup for out the back and verandah out the front!!!

Which suppliers are you using? Ive checked out Monaro, Thors Hammer, Fyshwick and the other usual suspects - I liked the homeliness of the Fyshwick Building Supplies.

Blu_Rock
5th May 2008, 11:00 PM
Great thread, now that I've moved to Queanbeyan I should get you around to give me some serious design inspiration I need for a deck setup for out the back and verandah out the front!!!

Which suppliers are you using? Ive checked out Monaro, Thors Hammer, Fyshwick and the other usual suspects - I liked the homeliness of the Fyshwick Building Supplies.

Welcome Namtrak. I started this thread because I wanted to try and pull together previous advice that has been given on the Forum along with my own experiences during the deck build. I have been dabbling in timber and metal for about 40 years and and even though I am somewhat experienced, each new project throws up unknowns and gives me the opportunity to continue to learn.

For this build I have mainly used timber from AJAA but to be honest, I have found them to be a bit difficult to deal with. While the owner has been fine and obliging in exchanging merbau that was either twisted, bowed or otherwise deformed, I have found some of the staff to be a bit surly. That said, their prices are competitive and in the case of the cypress 19x90 un-fluted decking that I am using for a screen that I am presently adding to the deck, they were the only supplier who had the cypress at a reasonable price. That said, I had to take back two lengths of the cypress for exchange, one was badly split and the other had 4 strap marks that would have shown. On the way out, I got a smart a$se comment from the woman on the front counter. While I can live with that, it's not really professional.

I have also used timber and hardware from Bunnings and Magnet Mart. Their prices are generally OK and at least you can personally pick and choose your timber.

I have used Thor's in the past and they have great service and an amazing stock of recycled timber.. albeit a bit on the expensive side.

Monaro timber has made their name supplying good quality timber and also gives good, friendly advice. A little on the expensive side but you get what you pay for.

In the past, I have used Fyshwick Building Supplies but on the last couple of occasions, their prices were un-competitive.

Also, try Ern Smith in Hume. When doing my bathroom/laundry reno, they were cheaper than everyone else for the gyprock and wet area materials.

For hardware, Keeler Hardware in Fyshwick has a huge range of hinges, draw pulls, locks etc etc and can get just about any thing that is hard to find. Good service there too.

For nuts and bolts, stainless fittings and other fasteners, the best is Speciality Fasteners in Fyshwick... they are even cheaper than Bunnings on some lines, and the service is way better.

For steel, it's either Andre Herzog or Metal Mart both in Fyshwick.

For plumbing, I have mainly used Reece or Southern Plumbing and have been satisfied.

No doubt there are others who can deliver the goods but the above has been my experience.

Good luck with your build and make sure you throw up a few photos so we can all see your handy work.

Blu

Robo
6th May 2008, 10:40 AM
Thanks Blu Rock, I may have used the wrong term when I said butt jointed. I actually cut a 1/4 inch piece out of the two end posts that the rail fits tightly into then either put two long screws in from the other side of the post or on an angle from underneath, countersinking the heads and bogging them over.

The extra support might be the best way to go. Shame that the post tops are about 2 inches above the rail. I'm thinking a support that just goes to the bottom of the rail might look odd. I suppose I could glue and screw a fake post top to the rail to make it match the others. When it is painted only an experienced eye (and myself) will realize what I did. I am also going to put several stainless wires around it and they probably need a support in the middle over 2.5 meters too.

Does anyone in ADELAIDE know of a good (reasonable prices) place to get stainless fittings. There seems to be a few ways of fixing stainless wires. Some that tighten up like a drill bit, others that need a clamping tool etc. Any advice in that area would be most welcome.

As for the splitting treated pine. What would you suggest making post caps out off? I water proofed the balcony with Gripset products before tiling it. Primer, fabric and blue rubbery compound (Gripset 38). There is also a strip of fabric and 38 that goes over the edge to give a good seal between the thick sheet and the wall. It got tiled on top and painted on the wall edge. (Hope that makes sense!) Anyway, I'm wondering if a bit of this fabric and compound would make a suitable sealer for the tops of the posts. I could also run a length over the entire top of the rail. It has a smoothish finish and when painted will be a lot better than cracks. Have you had any experience with doing something like this, or would I be creating more problems in the long term. i.e. If it is not intended for this purpose I could find it curling and up and falling off in a years time.

Blu_Rock
6th May 2008, 07:33 PM
Does anyone in ADELAIDE know of a good (reasonable prices) place to get stainless fittings.

Robo, on the Forum, when you are seeking advice that falls outside the scope of the thread you are currently reading, it is best to start a new thread and this will give you the greatest chance of someone seeing your question and responding to it. I suggest you start a new thread for this question.


What would you suggest making post caps out off?

I am not sure how you would go about making end caps or whether your proposed fix would last.

UteMad
7th May 2008, 01:06 PM
Robo, on the Forum, when you are seeking advice that falls outside the scope of the thread you are currently reading, it is best to start a new thread and this will give you the greatest chance of someone seeing your question and responding to it. I suggest you start a new thread for this question.



I am not sure how you would go about making end caps or whether your proposed fix would last.


OOOOOOOOh play nice people

Cheap place for stainless delivered to your door right across australia

miami Stainless

http://steel-fittings.com/index.htm?gclid=CLKr_Limk5MCFQKiiQodpkxCyg

cheers utemad

UteMad
7th May 2008, 01:12 PM
Interesting, I have 2 references that say twice the riser plus the going should equal between 585 - 625 mm. One reference is in 'The Australian Carpenter and Joiner' pg 541:
Riser = 115 min, 190 max
Going = 225 min, 395 max
2R + G = 585 min, 625 max

This is for external timber stairs.

Dont lose too much sleep .. the guys 10 doors up are building a set of stairs and landing up to a front door ... 4 guys to build it and the treads are 190 x 45 with a negative nosing of about 50mm ie the tread below is 50 short of making it to the front of the tread above... Definately not safe especially for pets and kids but it happens every day...
The list of things that dont conform to Aust standards on theis deck goes down to nearly every member size and connection method... I might even post it for all to see how not to do a deck

cheers utemad

UteMad
7th May 2008, 01:21 PM
Hi UteMad,

I have just had my decking plans approved from the local council. Before they would approve it they wanted some additional information eg step riser heights and tread widths. Since I'm using 90mm by 19mm Merbau my riser height was going to be two boards =180mm plus 3-4mm for the spacing. Tread width 4 boards = 360mm + 10mm for spacing and top of the riser board + 19mm. = roughly 390mm. Then the council made me aware that there is max tread width of 355mm. This kinda screwed up my nice wide step idea. I know there is a min tread width of i think 260mm but i was unaware of the max limit. Has anyone else heard of this? Just after reding your last post UteMad you mentioned that you have used 6 to 8 boards for the tread. Is this using 90mm or 70mm?
Also a little bit off topic but my deck at the highest point is 650mm off the ground and i have 90mm by 90mm Merbau handrail post and wire balastrading basically just for looks. I had the wire spaced on the plan at 200mm spacings to reduce costs a little but the council have come back saying that i must have them spaced at max 100mm width and certain tensions etc. Is this accurate if the deck is not higher than 1mt???. Any information would be much appreciated!

Thanks

Tim.

Never had a prob with the treads being too wide before and yes we use 90mm boards ... If you want 180mm rise with 90mm boards you'll have to run the riser boards under the front of the tread boards and behind the last board on the tread below or you'll end up with 205mm approx riser..
Draw yourself a diagram before you start to save confusion..
Handrails are a funny thing.. In sydney we don't need a handrail generally below 900mm to pass council.. I don't know if once you put one though whether it then has to comply to handrail rules.. The current stainless cable regs are about 4 pages chocker with specs and tensions so too much to spell out here..

Heres an example

Post distance 900mm
height 1000mm
cable centres 80mm
tension req 670 newtons
cables required 11
wire size 3mm
construction 1 x 19

Post distance 1500mm
height 1000mm
cable centres 60mm
tension req 790 newtons
cables required 15
wire size 3mm
construction 1 x 19



they are making it harder every day


cheers Utemad

Blu_Rock
11th May 2008, 09:09 PM
Had a bit of a busy weekend but I finally managed to finish off the deck's cypress screen that I have been working on for a few weeks. No more looking into my mess of a shed from the deck. I used slightly wider 5mm gaps between the Cypress, rather than the 3mm gaps between the merbau decking.

I am pretty happy with how it turned out and it is stained with Feast Watson Decking Oil, natural tint. The lighter timber looks a tad yellowish so the majority of the lighter stuff is facing out toward the drive. As per the deck, I used stainless screws. The screen still needs another merbau rail across the top, so I suppose it's still not finished.

Next weekend, I will probably try and finish off the handrail and (hopefully, make a start on the other set of stairs leading down to the drive. These stairs will conform with the 2R + G formula that seems to have generated so much discussion.:U

mattwilliams78
11th May 2008, 10:25 PM
Nice deck Blu_Rock, looks good :)

roba
11th May 2008, 11:46 PM
How high is that cypress screen?

Blu_Rock
12th May 2008, 08:31 AM
How high is that cypress screen?

The screen is 1620mm to the top of the cypress slats and 1900mm to the top of the top merbau rail, yet to be added. It is 4.5m wide.