One for the builders (Re Decks)

[Sir Stinkalot]

With the Stink having a few more weeks off before returning to work the Stinkette has commissioned him to replace the steps that he removed about two years ago, affectively rendering the side and rear doors of the house useless.

Now as I normally design, not build, I have come humbly to ask the advice of the builders on this forum.

Attached is a JPEG of what I am looking at doing. The deck and stairs are, 500mm above ground level, the landing is to be 3000x900 with steps at the end. I want to use decking timber for the stair tread so the main deck direction needs to be perpendicular to the house.

Here are the plans.

Attach 290x45 TP ledger to the house.

Put in the three posts along the long edge and one in the middle. The additional post along the long edge is to attach decorative decking boards vertically along this face.

Put the two bearers (290x45) in running perpendicular to the house, and a joist (290x45) running parallel.

The joist will be supported in the middle to prevent any deck bounce.

Attach the middle joist 290x45 TP to the bearers with joist hangers

Add on the decking and the stairs and we should be done.

I was thinking of using post stirrups set into the concrete but the last time that I tried this the concrete shrunk when drying and the stirrups wobbled ….. what did I do wrong?

Now if there are any problems with the above please state your case now …..

Ok one final question ….. I have sized up the joists and bearers (290 x 45) with the assistance of Allan Staines “Decks and Pergolas” …… timber this size will cost me $14.50 plm for treated pine. Please tell me the reason why I can’t use 200 x 50 TP Sleepers at $15.00 for a 3m length. I know that the book says 290 x 45 but I can’t see much difference with the 200 x 50 as I am only spanning 1500mm at most. As the deck is only 500mm from the ground it isn’t going to kill if it fails but I have a fear that the sleepers will warp all over the place. I am just interested in hearing opinions before purchasing the timber.

Thanks

Sir Stinkalot

[journeyman Mick]

Stinky
welcome back, long time no poll! Being an architect and all you would know that a picture speaks 1K words. I started reading your description of your plan and just dazed out (still in holiday mode myself). How about a drawing of what you want to do? It doesn't sound right to me, but, like I said I just started dazing out reading it.

Mick :confused:

[Sir Stinkalot]

Hi Mick ..... I was hoping that you would be out there. I have attached a JPEG with my good self standing at the door ..... :)

[Sir Stinkalot]

A plan view ;)

[journeyman Mick]

Stinky,
according to my tables an 1800 span joist only needs to be 120 x 35 in F4, so a 200 x 50 sleeper should be just fine. The same tables show a bearer 1200 span @ 3600 crs to be 140 x 70 in F4. I avoid stirrups as they do tend to flex if the post is not braced in two planes. I prefer paired fish plates as they give a much stiffer post which requires less temporary bracing during construction. Less bracing = less timber, pegs & time. I usually screw or tape them to a scrap packer to get them the right distance apart and push them into the concrete once it's been placed.
One problem I can see though is your stringers. You'll need to have a centre stringer in order to support your decking at 450 crs. Even with that support it may still flex too much as you tend to apply more load when walking up and down stairs. I would sugggest that you spend the money saved on your subfloor (and by deleting a 3rd stringer) on more substantial treads.

Mick

[Sir Stinkalot]

Thanks Mick ..... I knew that you would come up with the goods. :)

I think that my timber sizes must have blown out a little when I was drawing it up and threw in a few more posts.

I wanted to use the decking timber for the stair treads as I prefer the continuous look of having the decking and treads out of the same material. I had always planned a third and possibly fourth stringer to prevent the step bounce.

So in your opinion do you think that the 200 x 50 TP sleepers will be adequate to build the sub structure out of? I am concerned over any warpage or splitting. I know that the size will prevent any bounce but I am concerned that the sleepers should be left in the garden and not the deck.

[DaveInOz]

Um ..... whats a fish plate?

[silentC]

So in your opinion do you think that the 200 x 50 TP sleepers will be adequate to build the sub structure out of? I am concerned over any warpage or splitting. I know that the size will prevent any bounce but I am concerned that the sleepers should be left in the garden and not the deck.

I reckon that there's every chance they'll warp or twist. Sleepers are nearly always delivered green and sopping wet. I've got some in the ground that have held their shape fairly well but I don't think I'd like to build anything on them and expect them not to move. You're better off getting kiln dried T/P. You'll also find it easier to work with.

[silentC]

Um ..... whats a fish plate?
Poisson du jour. :D

Two steel plates with holes drilled, one either side of the post with the ends embedded in concrete and bolts through the post. Same thing they use to join railway tracks, which is where the name came from, although I'm not sure why "fish plate".

[DaveInOz]

Poisson du jour. :D
Mate, sounds like a red herring!

Ta

[silentC]

A fish plate is a metal or wooden plate that is bolted to the sides at the ends of two rails or beams, to join them. A fish plate does not have anything in common with the aquatic fish. The fish in this term is derived from the French word ‘fiche’, meaning a peg. ‘Fiche’, in turn, is derived from the old French word ‘fichier’, which means to fasten. Thus a fish plate means a plate that fastens.

Doncha love the web?

[Fat Pat]

Now you are just CARPing on!

[journeyman Mick]

All the fish plates I've ever seen have a split up the middle of one end with the two pieces curved, one up, one down. I'd always thought they were called fish plates because of this "tail".

Mick

[silentC]

Wouldn't be at all surprised if that was true...

[journeyman Mick]

Stinky,
I've never used anything other than hardwood for subfloors. I don't think I'd feel comfortable nailing a deck into treated pine joists. Pine just doesn't hold onto nails that well resulting in popped or squeaking boards. I guess I would consider pine joists if I was using Dektights. These are a small metal bracket that nails to the side of the joist. It has two spikes that sit on top of the joist and the edge of the decking is spiked onto it. This way the nails are in shear rather than being pulled straight out.

Mick

[HappyHammer]

Stinky,

Which way up are you putting the decking timber? :eek: :rolleyes: :D

HH.

[silentC]

Jeez Mick, the subbies would love you down here. I don't think anyone has used hardwood here for 10 years or probably more - too hard to drive a nail into. All the sub floors are treated pine - especially in decks. They don't even bother with the old bitumen flashing on the joists. Hardwood or T/P deck straight onto the T/P joist with a couple of gal Tita-deck dome head nails.

[journeyman Mick]

I like to think that the things I build will be around a lot longer than me! If we're going to cut down forests we should use their products in a way that maximises their use, value and longevity.

Mick

[Sir Stinkalot]

Stinky,

Which way up are you putting the decking timber? :eek: :rolleyes: :D

HH.


Grooves down for me :)

[Peter36]

Treated pine is commonly used for deck joists in Melbourne - the hardwood that is available here is not suitable for use in exposed decks - and spiral Gal "Titadeck" or stainless steel nails used to fasten the decking . Takes a lot to pull the buggers out .

[Jacksin]

Stinky, just an observation, if I may.

It seems an awful lot of work for a landing only 900 wide. I take it you will install a ballustrade to stop people / kids walking or falling off the edge and suing the crap out of you. Why not double the width (as a minimum) to make it more accessible and look a bit more classy?
Jack ;)

[Sir Stinkalot]

Stinky, just an observation, if I may.
It seems an awful lot of work for a landing only 900 wide. I take it you will install a ballustrade to stop people / kids walking or falling off the edge and suing the crap out of you. Why not double the width (as a minimum) to make it more accessible and look a bit more classy?
Jack ;)

Jack ....

The landing is on the side of the house and there is only 1800mm clearence to the fence ..... I still need access for the lawnmower etc so the landing can only be 900mm wide. Previously we had concrete steps as soon as you walk out the door but it really was nasty. As the deck is only 500mm from the ground there is no need for a handrail (BCA) so I am not going to bother. A handrail will also increase the visual bulk of the stairs and landing and as this is in the middle of the path down the side of the house I want to avoid that.

Stinky.

[HappyHammer]

Why not extend it to the fence and put a ramp on either side, this gives you the size, requires no ballustrade and enables easy movement of the mower although at 25 you should be able to pick it up and carry it.:D :D

HH.

[Sir Stinkalot]

The deck really isn't a functional entertaining area ...... we have that out the back (well when I finish the garden walls and get the paving done :)) ..... Basically we just wanted to have a landing so that you could put down the washing basket, take off and store your shoes etc before opening the sliding door. Previously we walked out the side door straight onto the steps ..... I prefer a landing rather than opening directly onto the first tread.

I have resized all of my members and now they are much easier to handle, it has also reduced the price and I will now use Jarrah decking. Now I just have to wait for Melbourne's weather to clear so I can make a start.

[Pulpo]

Mick

Sorry I know your on hols, but my hols consist of picking up the tools and having a DIY hat on.

With hardword sub-floor for the deck;

What nails do you use?

And can you use a nail gun? and interested to know what sort of nail gun.

Thanks for the fish plate idea, never heard of them either.

Also Sir Stinkalot

I would not be using the standard sleepers 8ft or 2.4m as they are often split after a few months, that's my experience and I have purchased quite a few over the last few years but from the one source, 3m might be a little different, I do not know.

Good Luck either way

Pulpo

[HappyHammer]

My Dad has built a few decks back in blighty and he uses screws not nails :eek:

HH.

[journeyman Mick]

Pulpo,
bearers bolted to checked out posts, joists trip-l-gripped to bearers - minimum of 10 nails per grip.

Mick

[Simmering]

I reckon that there's every chance they'll warp or twist. Sleepers are nearly always delivered green and sopping wet. I've got some in the ground that have held their shape fairly well but I don't think I'd like to build anything on them and expect them not to move. You're better off getting kiln dried T/P. You'll also find it easier to work with.
I've only just seen this thread, though I'll add a late thought as I can't see where the decision about using sleepers ended up.

There is no way that I would use sleepers. Sleepes are cut and processed green (very unseasoned). That is why so many cup, warp, split etc. The timber sizing that has been quoted appears to be for seasoned hardwoods. I would be concerned using unseasoned timbers on a deck as when they season (unevenly) the resultant deck will be undulating. Why waste a great landing/deck with a poor substructure?

Anyway, best of luck

[Sir Stinkalot]

Hi guys ....

The deck is well and truley under construction now.

I ended up using 140x45 dressed tp for the substructure.
Despite looking around for fish plates I couldn't find any so I had to go with the sturips.

What I have found from my experience is that the cost is in the bolts, nails, joist hangers, new drill bits etc more so than the timber.

The substructure should be finished today and then I will wait a little while before putting the boards on.

[Ramus]

Sorry to drag up an old message but am about to embark on deck construction myself. My question - Is it possible to just have hw or treated pine posts cemented in the ground (height will be from 300mm to 600mm) rather than the stirrups or fish plates?

[onholidays]

I actually wanted to know what software Stinkalots using to get those designs?

[Sir Stinkalot]

onholidays ..... the program is ArchiCAD 8.1 ...... not really great for woodworking or decks for that matter but as I use it every day I find it the quickest way to do things ..... even things it isn't good for :)

If you are after woodworking software do a search as there has been a discussion not long ago.

[Sir Stinkalot]

Sorry to drag up an old message but am about to embark on deck construction myself. My question - Is it possible to just have hw or treated pine posts cemented in the ground (height will be from 300mm to 600mm) rather than the stirrups or fish plates?

Ramus .... I thought that somebody would have replied to this by now ..... if you are to embark on a new deck yourself I would suggest that you go by the bookshop or libray and get a copy of "The Australian Decks & Pergolas Construction Manual" by Allan Staines. ISBN 1 875217 10X.

I picked up a copy in a second hand bookshop for $10 ..... well worth a read .... it covers a number of situations for decks and pergolas.

Ok now your question ..... from the above mentioned book .....

Hardwoods of durability class 1 can be used in-ground.
Treated timber: H5 for inground. H4 can be used in some states for moderate hazard applications, if uncertain use H5. In a continually moist situation use H6 treated softwood. The bottom ends of treated timber should not be trimmed as this could expose untreated heartwood.

The book does indicate that stirups are best if possible.

Hope this helps.

Stinky