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Calculate the price of a deck - Mother of all posting!!
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Author:  Adrian B [ Sep 13, 2007 8:47 pm ]
Post subject:  Calculate the price of a deck - Mother of all posting!!
OK guys

Here is the ROUGH ROUGH costings for a 10 x 5m deck (50 sq metres). I am only talking costs of materials but this will give you an idea.

Definitions:
Posts - Poles that go into the ground
Bearers - Sit on the posts to hold the joists
Joists - Sit on the bearers to hold the Decking. If timber, the bearers should be rebated half way into the post. If Concrete posts, drill ahole through the timber for the rio rod to poke through, then bend and hammer over into place

I have taken part of the Mitre10 Do it yourself plan to show what is what.

Assumptions:

1. THIS IS A VERY BIG DECK!!!!
2. Deck is level, only 50cms off the ground (ala an alsfresco area)
3. Soil is not too sandy (effects the depths of the support posts)

Timber prices

Decking----------------------Merbau----------70mm x 19mm----------@ $3.40pm (per metre)
Bearers----------------------Hardwood----90mm x 45mm----------@ $4.20pm
Joists-----------------------Hardwood--------100mm x 50mm---------@ $5pm
Posts------------------------Treated Pine----100mm x 100mm--------@ $10pm
Fasteners--------------------Galvanised Screw nails ----------500g @ $10 kilo = approx 280 nails
Bolt sets--------------------100mm x 10mm----$1.20 set
Concrete---------------------20kg------------$6 per bag.
Sand-------------------------Bricking sand-------------$50 cubic metre
Rock-------------------------Gravel - no sand----------$50 cubic metre
Glue-------------------------Liquid Nails----------Tube----------$5 ea
Nails------------------------100m x 3mm Building nails (someone help me out here) $10 pkt

Bearers run the same way as the final decking boards

For solid decking, posts need to be 1.4 metres apart max.
Bearers the Same - 1.4m apart
Joists 45cms apart.

Working on this, you will have the following requirements (I have rounded up)

Posts 40 (8 x 5 ) 100cms long= (60 cms into ground) = 40m @ $10pm --------------------=$400
Bearers 8 @ 5 metres = 40metres @ 4.20pm --------------------=$168
Joists 11 @ 10 metres = 110 metres @$5 pm --------------------=$550

Decking

Here is how you work out how much decking you will need.

The ideal gap between 70mm boards is 3 - 4mm, or a medium size rounded screw driver. So in 1 metre of deck you will have 13.4 boards (100cms / 7.5). Seeing as you cannot buy .4 of a board in thinknes, you need 14 boards @ 1 metre each.

Therefore @ 3.37pm 1 square metre of merbau decking costs $47.18
x 50 square metres = ------------------------------=$2360

Concrete and sand

Mixing concrete and sand will save about $70 - 100 as you wont need as much concrete. I would add some gravel in there as well for stability.

10 bags plus 2 mtre sand plus 1 metre rock ------------------------------=$200

Nails - More you buy, cheaper the cost. 2 nails per connection between
the bearer and joist------------------------------=$120.00

40 Bolts----------------------=$48

Liquid nails stops any squeaking - cheaper by box of 25--------------------=$approx $80

= $3986
Add in cement mixer hire and a fex sundries and allowances for more timber if I have missed cannot think of - say MAX $500

= $4,500

It will NOT cost $8,000 in labour to build it.

but if you want to pay that, give me a call!!!!!!   ⋅  Add a comment  ⋅  Pin to Ideaboard  ⋅  
Author:  Adrian B [ Sep 13, 2007 9:36 pm ]
Post subject: 
To give you an idea this is about 45 square metres.   ⋅  Add a comment  ⋅  Pin to Ideaboard  ⋅     ⋅  Add a comment  ⋅  Pin to Ideaboard  ⋅     ⋅  Add a comment  ⋅  Pin to Ideaboard  ⋅  
Author:  _Al_ [ Sep 14, 2007 9:18 am ]
Post subject: 
Excellent information. :D
Author:  vanderlay [ Sep 14, 2007 9:45 am ]
Post subject: 
yep, thats really helpful! Thanks!

Decking is one of our first big projects after handover!

(Deck, Driveway, Window Coverings!)
Author:  connexion [ Sep 14, 2007 10:01 am ]
Post subject: 
Thanks Adrian for the excellent information. I am planning to do my own deck next weekend. I got a quote from Lumber Softwoods in Dandenong South $1880 for 25 square m. They are very helpful and did all calculation based on my plan how many m of posts/bearers/joists and decks I need.

Just a couple of questions:
1.Is it safe to stick a ledger against the brick wall without getting an engineer to look into this? I am worried about whether the brick is strong enough to hold the load.
2.If I were to use the post instead of ledger, what is the minimum distance from the wall? I am worried that if I dig the hole for the post, it might interfere with the termite protection underground.

Thanks.
Author:  Adrian B [ Sep 14, 2007 10:27 am ]
Post subject: 
I would stay away from a ledger against the house for a couple of reasons.

1. If the house moves for some reason, so will the deck.
2. Some councils require you to have a building permit if the deck is attached to the house.
3. As you mentioned structural integrity of the ledger and brickwork.

None of my jobs are attached to the house. the posts are about 300-400mm in from the edges, bearing in mind that the bearers can run the width to the house. Just leave a 5-10mm gap between any existing structure and the edge of the bearer.

On the front porch, the top step is dynabolted to the concrete porch slab, but the first step down is separate construction. Only a couple of gangnail plates to ensure minimal movement. Did this so that if the house slab move, the top deck would move freely from the rest of the decking, but not move under foot.


Hope this helps.

Good luck, keep us posted on your progress.
Author:  Adrian B [ Sep 14, 2007 10:31 am ]
Post subject: 
Further to the MOAP above.

You can also use concrete posts in place of the Treated pine posts. Ths can save a bit of money, the only thing to thinnk about is that if you need to put steps in, you canoot cut rebates into concrete. Some of the larger hardware places (not necesarily bunning etiher) stock 100 x 100mm concrete posts in lengths incrementing 5 cms.

Shop around, use what is good for you and your job.
Author:  connexion [ Sep 14, 2007 10:36 am ]
Post subject: 
Thanks very much Adrian. Your suggestion makes sense.
I will change my plan and shop around this weekend.

Thanks again.

Jim
Author:  Adrian B [ Sep 14, 2007 11:37 am ]
Post subject: 
Dont forget to predrill all holes into merbau to prevent splitting, get a good quality well weighted hammer (on the heavy side, trust me) and cold beer.
Author:  _Al_ [ Sep 14, 2007 11:43 am ]
Post subject: 
Adrian B Adrian B
Dont forget to predrill all holes into merbau to prevent splitting, get a good quality well weighted hammer (on the heavy side, trust me) and cold beer.

Now I'm getting fussy, but flat headed nails or domed top ones? Closeup pic?

Buy more than one drill bit also.

Timber should be grooved side down. Otherwise you will have loads of water sitting on the boards waiting to rot through them.

And the cold beer goes without saying doesn't it?
Author:  Adrian B [ Sep 14, 2007 11:52 am ]
Post subject: 
They are galvanised rounded . From Mitre 10 they are Otter TITADECK, and from Bunnings they are TIMBERLOK.

The heavy hammer is a godsend.

While you are there, buy 3 cheap scerwdrivers (the same screwdriver) that have a metal stem of about half a cm.

Why I here you ask?

This is a fast way of laying the decking boards giving you an even gap all the way through.
Author:  _Al_ [ Sep 14, 2007 12:10 pm ]
Post subject: 
Adrian B Adrian B
They are galvanised rounded . From Mitret10 they are Otter TITADECK, and from Bunnings they are TIMBERLOK.

Thanks

Quote:
The heavy hammer is a godsend.


Yep, absolutely. For nailing weatherboards and cement sheet prior to flooring.

Quote:
While you are there, buy 3 cheap scerwdrivers that have a metal stem of about half a cm. Make them the same screwdriver.

Why I here you ask?

This is a fast way of laying the decking boards giving you an even gap all the way through.

While making sure your first one is straight :lol:

Good tips.
Author:  Adrian B [ Sep 14, 2007 12:15 pm ]
Post subject: 
Absoluteley the first one must eb straight. Kinda helps...
Author:  ewan [ Sep 14, 2007 12:17 pm ]
Post subject: 
wish i could build a deck. saves me heaps, and yes i've been quoted 8000 for smaller decks :(
Author:  Sallyho [ Sep 15, 2007 3:53 pm ]
Post subject: 
Adrian this is a most informative post, thanks for taking the time to pull it all together and share with all of us.

As you are aware this is most useful to me.

Thanks!! :)
Author:  arkraider [ Sep 18, 2007 12:10 pm ]
Post subject: 
Quote:
Adrian B wrote:
Bearers run the same way as joists.


Sorry Adrian, don't mean to be picky as I am far from an expert on this topic... But I think you were meaning that the bearers sit on top of the posts and the joists on top of them at 90 degrees and the decking sits on top of the joists and run the same way as the bearers...only going off the pic you supplied.....

great completed pics, very similar to what I want to acheive in our house, when it is completed.... we still have to start yet... hell we still have to get the titles for the land first...... :lol:

P.S. I also saw you are willing to do this for approx $105 p/metre.... I may take you up on that and then you can show me how this works... as I don't really have the confidence to tackle it myself....but very willing to learn...
Author:  Adrian B [ Sep 18, 2007 12:13 pm ]
Post subject: 
I stand corrected. Should read the Bearers run the same way as the decking boards.

Deck sits on joists which sits on bearers which sits on posts (or concrete.

As for the offer, I was joking!!.

That said, you can easily guage how much the materials will costs, so that will give you an idea on the cost of labour and markup. Example: I drilled and hand nailed every single nail in both decks. A pro will rpobable use a nail gun, and not predrill. Your choice, but I dont think you can get twiseded galvanised decking nails for nailguns.

Hey I never did it before either, but it all comes down to planning, preparation, the right tools and some common sense, research and asking dumb questions.

I have a DVD which explains a heap. send me a PM with yr address and I will see what I can do.
Author:  arkraider [ Sep 18, 2007 12:21 pm ]
Post subject: 
Bloody good post though Adrian.... have already printed it out and filed it in with all my other info for the upcoming house project and to do lists....
So thanks for the great details......and plenty of them which is good as I have most of the tools to do the job, but they are in very new condition if you know what I mean..... and the tools that have been used to an inch of their lives belonged to my father...... :)
Author:  off2theburbs [ Sep 18, 2007 6:43 pm ]
Post subject: 
thanks for this post makes it so much easier to see how much money we need to do this without forgetting the little things :roll: you know the ones that you take countless trips back to bunnings to get
Author:  wonderland [ May 29, 2008 11:36 am ]
Post subject: 
Sorry to bring this thread up again. Wanted to say thanks for the post, it was very informative!!

Just wanted to ask one question, how did you build the step down from the deck?

many thanks. :D
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