Some advice about DECKS needed

[Lenny]

Hey All,
This is my first post, and i'm requesting some advice about a 8m x 2m deck i'm going to build over the Xmas/New Year break. Now, this is my first big project and i'm getting all tooled up for the job. Its going to be on the south side of the house and not covered, so its going to get pretty much all of the weather. I need some advice on materials. What are the advantages/disadvantages of using the following:

- Red gum or Jarrah Cypress Pine or Treated Pine STUMPS
- Unseasoned Hardwood or Treated Radiata Pine BEARERS
- Unseasoned Hardwood or Treated Radiata Pine JOISTS

Any information would be helpful. Thanks Guys

[Trav]

Gday Lenny - welcome. A deck was my first big job too.

FWIW, I used treated pine for all the substructure. It is cheaper I think and pretty easy to work with. Plus it is not all that palatable to termites and is easy to find. Best if you use stirrups where the posts meet the ground.

Alan Staines has written a good book on decking and pergolas. It is available at bunnings and it is certainly worthwhile if you are building your first deck. It gives you all the span tables and timber sizes.

Here is a link to photos of my deck. http://www.woodworkforums.ubeaut.com.au/showthread.php?t=20204
There are some great deck photos on these forums too. Search for decks and you will see some pearlers.

You might also have a look at my post on this thread http://www.woodworkforums.ubeaut.com.au/showthread.php?t=23197

It has a pic of a jig I made to keep all the nail holes straight. It may be of interest to you. Or maybe not.

Good luck - sing out if you hvae any other questions.

Trav

[Bodgy]

Lenny, you don't mention the planking?

I'd make the point that this will bear the brunt of the weather. If you're South facing, and like me, you don't get a lot of sun due to trees, you should bear in mind two things:

1. The damp will persist for a while after rain, potentially causing rot issues in any joins
2. The surface can get very, very slippery if just finished timber

I'd also suggest you leave spacing between your planks for drainage and airflow, dont butt them up like and internal floorboard.

I used upside down green pine for the decking, but others will be more knowledgeable.

[Lenny]

Thats some good info.

Trav, you have settled my mind on treated pine.

Bodgy, yeah, i think me and the Missus have our hearts set on Jarrah decking/planks. I do plan on having at least a 4mm gap between the planks. I also plan on using some agy pipe to aid drainage under the deck. Its just in a really odd location, the deck, that is.

Now all we have to do is decide on a stain or oil for the decking.

[maglite]

Now all we have to do is decide on a stain or oil for the decking.

Lenny,

If i can make a suggestion.
If you can, try a few different products on some scrap first to see wether you like the finish.
I bought ltre tins of 4 different products to see wether i liked it and left the scrap out in the weather for a few weeks before i settled on the oil that i used.

cheers
Steve

[Trav]

Lenny

4mm is a big gap mate. Small children might fall though! I think 2mm should be OK. I used some old 1.8mm nails I had lying around as spacers - they worked a treat.

Once I had installed the posts, I laid some weedmat (the stuff water can seep through) and the covered it with 40mm (ok, so I got tired and it was more like 20 or 30mm) of gravel to assist with drainage and keep the weeds down. Its worked a treat and looks neat. But it adds an extra few days to the job.

Make sure you paint the treated pine before you add the decking. At least paint the top of the joists etc.

Jarrah would be great - but kind of expensive. I used spotted gum, which is as hard as hell, but looks good IMHO. I used wattyl decking oil, but others recommend spa n deck and sikkens.

Trav

PS - last bit of advice for now - I think it is worth scrubbing your deck down after it is laid and before you oil it. I didn;t and I had all these black spots appear. I guess they were mould. They are a bugger to get rid of.Others may have a view on this too.

[leeton]

I don't reckon you can beat concrete stumps...cheap as chips too...that's my 2 bobs worth.

[burn]

Given you go with the treated pine and whatever for the decking itself, don't forget to NOT purchase the wood from your local Bunnies or the like. Find a local mill - check your yellow pages. You can save between $3 - $5 per metre by buying the timber from a mill rather than a general hardware store.

[maglite]

Burn makes a good point.

I reckon that i made a saving of 50% plus buying mill direct.

[Lenny]

Ok to consolidate this great advice.<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p>
<o:p></o:p>
- Weed matting and gravel under the deck<o:p></o:p>
- Paint the Joists<o:p></o:p>
- Use 2mm gap between the decking planks is good<o:p></o:p>
- Test oils on decking planks before choosing which type<o:p></o:p>
- Scrub down decking before oiling<o:p></o:p>
- Buy decking wood from a mill<o:p></o:p>
- Treated Pine is good for the substructure<o:p></o:p>
<o:p></o:p>
<o:p></o:p>
Now the questions:<o:p></o:p>
<o:p></o:p>
I have been advised against using a cordless gas operated framing nail gun. I have been told that using 3-inch Galvanised Decking (coffin) nails and pre-drilling the planks is best. Is this a good idea or bit of waste of time?<o:p></o:p>
<o:p></o:p>
Re: Scrubbing down the deck before applying the oil/product, what do you suggest with? Do you mean with soap and water and a basic scrubbing brush or something more elaborate?<o:p></o:p>
<o:p></o:p>
Re: Painting the joists, is this with simple house paint to keep the rotting a bay?<o:p></o:p>
<o:p></o:p>
Thanks
Lenny

[Trav]

I think you are on the right track with your summary.

Questions:

I didn;t use a nail gun at all. In retrospect I probably would try them out as it took me ages. Certainly pre drill all the holes at the end of the boards - you might be OK on the other joists.

Scrubbing the deck - I used a decking cleaner like Feast Watson or something. I bought a very stiff bristled broom (like a scrubbing brush on the end of a broom) from bunnings to use. I didn't fancy srubbing a 30sq m deck on my hands and knees.

I painted the joists with an exterior paint. I actually painted all the joists as I hate the look of treated pine. If you are just painting the tops of the joists, buy a mistint from a paint shop or bunnings in a dark green/brown/grey/black kind of shade. I don't think bright pink would look too flash. And yes, it is to stop rot as the area between the baords and the joists is the place most likely to rot.

The Alan Staines manual is certainly worth investing in. Even if only to check your spans and timber dimensions.

Trav

[Lenny]

Thanks Trav.

All good advice.

Hey, Nice deck too, by the way.

[handyandy2]

Hi Lenny

The other advise I have been given is to cover the bearers and joinst with that black foil. Just on the top and folded over each side by 2cm.

The weathering of the wood happens on top where the water lies so by covering all the top sides you will lengthen the time the wood will last. Don't cover the wood completely as it still needs to breath

Cheers