Screw or Nail Decking

[corey]

I am replacing the boards on the deck of an old queenslander. The joists are 50mm by 100mm and at 650mm centres. I am using 145mm hardwood decking as the replacement. Is it better to screw or nail and if so what size/type of screw or nail. What is the best method at the joins as I only have 50mm to play with?

[seriph1]

Hi Corey and welcome to the forum. You should find a HUGE amount of info here and a lot of folks willing to help.

The joists sound fine and are pretty much what most of them were done with I believe. Personally, I would nail the decking and predrill the ends to avoid splitting. A nail gun is a godsend in this application. Galvanised or stainless steel nails are what you will have to use as plain steel will rust pretty fast I believe. 50mm is the go I think (check with others), depending of course on your decking's thickness. If nailgun-ing them, I also think the nail heads should "just" break the surface NOT go right in. Decking nails have a rounded over head. Do you know the species of hardwood and is it decking timber or flooring? Pics of the home if you have any please

[corey]

Hi Corey and welcome to the forum. You should find a HUGE amount of info here and a lot of folks willing to help.

The joists sound fine and are pretty much what most of them were done with I believe. Personally, I would nail the decking and predrill the ends to avoid splitting. A nail gun is a godsend in this application. Galvanised or stainless steel nails are what you will have to use as plain steel will rust pretty fast I believe. 50mm is the go I think (check with others), depending of course on your decking's thickness. If nailgun-ing them, I also think the nail heads should "just" break the surface NOT go right in. Decking nails have a rounded over head. Do you know the species of hardwood and is it decking timber or flooring? Pics of the home if you have any please

Thanks steve. The decking is 145mm * 19mm Vitex from New Guinea (Dont go into the rainforest thing, already copping it from the wife!!) I was looking into buying a nail gun and compressor. I only need it for around the house stuff so would a compressor and equipment from the discount auto shops suffice. What sort of nail gun would i need?

Corey

[Gaza]

i would go for the screws as hardwood does tend to split when nailed by gun. Also check if 19mm decking is ok to span 650mm cc i would say you may need a thicker decking to aviod any "spring" in the deck.

[seriph1]

decking guns can be hired I believe - that's how I did the last job for a mate. best to ask a tool place about nail guns I reckon..... as I am NO expert - auto parts compressors or bunnings ..... same type of product(GMC or similar), but easier to get replaced from bunnings when they break down......KEEP RECEIPT as they need it when replacing them, which they do without question. Try and get one model up from the base, is my motto.

[seriph1]

screws "can" be the way to go but take a huge amount more time to fix and if you twist the head off one, it is a big job to remove when it's the last one on that board. Nailing pre-drilled holes is the best solution I believe. What we did was set up 2 man teams - one person drilling, one nailing and making sure the boards were straight when the nails were inserted. and I was remembering incorrectly when I said we drilled and nailgun'd the ends - I recall now that we drilled and hand nailed the ends. I remembered because we used those nails as the spacers to keep the boards an even distance apart. Remember to do all you can to nail the boards in line, as it can look ugly if the nails are all over the place.

[ausdesign]

Greetings Corey.

I'd be checking out the decking span with the suppliers - 650 seems way too much spacing. In the new reg's there is also a difference between 'high' & 'low' decks in regards to spans.

My preference would be for 50mm gal nails [predrilled with a one eighth bit]in preference to screws. Screws have a tendancy to sheer off especially if drilling into seasoned hardwood joists, as yours will be if they've been down for a period of time. Plus depending upon the hardness of the decking in my experience, screws can tend to spin & not seat properly below the surface.

As an aside - It sounds as if your joists may be in good shape but normal hardwood joists [obhw f8] are not suitable for exposed use, although over the years they have been commonly used for decking joists. New reg's don't allow them. If your doing a large area with a fair bit of outlay i'd be looking at sealing the top of the joists with a bitumin paint or similar to protect the joists from rotting.

[seriph1]

Hi Pete - his deck "may" be undercover if it is the type of Queenslander we lived in as kids..... but all good points.

Corey - if the spans are too great there are a few non-drastic things you can do to remedy it. I am personally not fussed by the 650 even though it is over-distance for new places. I feel it would be most improbable that one could go through it once it is all on.

[conwood]

Hi Corey,
Irrespective of what you use, it's a good idea to cover bearers with plastic or similar before placing deck over them. Just that added protection from the elements.

If you can afford it, stainless screws are good, particularly if you may need access under at some stage. You can always unscrew and replace without bashing things.

Cheers,
conwood

[corey]

Thanks Steve

Yeah the deck is under cover as you suggested and the joists are very "Seasoned" as the house is about 100yrs old but they are in good shape. Not much I can do about the spacing but the old decking that is on it still manages to hold me up at 115kg so it should be ok. All points taken and much appreciated. The deck is only 2.4m * 8.5m so I may be doing a lot of pre drilling and hammering with a one eight bit and 50mm gal nails. Should I use twist nails?

[seriph1]

I never used twisties but it may be advisable - perhaps a tradie can advise. If you do want to reduce the span, you can marry-in members beside each joist, though as you say, it currently holds your waif like frame no problems.



one further hint - get three new HIGH QUALITY 3mm drill bits...... will save downtime resulting in finding your car keys in the middle of it all

[Trav]

I built a deck from recycled hardwood. The whole bang lot was drilled then hand nailed as its construction was spread over a few months.

I used 50x2.8mm hot dipped galvanised twist shank nails (what a mouthful). They wored a treat.

I would definitely stay away from screws:
1. more expensive
2. if the head shears off, it is a pain in the arris to remove - if you bend a nail, just rip it out
3. MOST IMPORTANTLY, screws will not at all fit the look of a queenslander. New deckign nails will look a bit out of place, but SS screws all over the deck will really look bad (IMHO). The heads of the screws are much bigger than the heads of nails and are much more noticeable.

I made up a jig (see picture attached) that enabled me to get all my nails in a neat line and gave me a guide as where to drill. I used 2.5mm (or maybe 2mm) drill bits (lots of them cos I broke them pretty regularly).

Have a look at http://www.woodworkforums.ubeaut.com...ad.php?t=20204 to see how my deck wored out.

Trav

[seriph1]

Trav, were you intending to post a pic of the jig? I couldnt find it on the link

[Trav]

Trav, were you intending to post a pic of the jig? I couldnt find it on the link

Ooops, my bad.

Here is the jig I mentioned.

Trav

[Firewalker]

At the risk of going against the grain......I would use SS screws and fasten from below. The nails will eventually pop over the years without regard to insertion method. Sure the nail gun is faster but it is worth the time and added expense (to me) to have the holding power of screws.

The method of fastening from below will prevent having to look at any fasteners or having to try to line them up. There are fastening systems made for this application. If you do end up doing them from the top side I would snap a chalk line and put the screws (or nails if you insist) on the line. Will make for a nicer look in the end.

Best of luck.

Scott

I found a link for you to see what I am talking about. Would be worth it if you want it to look top notch!

http://www.westessexbuilding.com/deckmaster.htm