Canberra Deck, photos up - help need with nails

[PRKLCD]

Hi all,

have been reading this forum for a while now but this is my first post.

Started building our first deck - what a great help this site has been. I have have posted up two photos which are a couple of weeks old ( I will post up more soon ). As you can see it's going to be a low lying deck.

I am actually almost ready to lay the decking ( Merbau ).

I am hoping that some people might be able to post up some photos of their deck using SS screws as fastensers - I have been looking at nails and screws but I really really don't like the look of screws ( I think the head is too big ). Hoping to see some photos of finshed decks.

Otherwise what nails would be best to use? Titadecks? I have a friend who used nails out of a nail-gun ( cause they like the look of them) pre-drilled and hammed in by hand - what do you think of this option?

[Pusser]

Why not hire the nail gun?

[PRKLCD]

Why not hire the nail gun?

I have heard bad things about nail guns - I would perfer to pre-drill as well, I don't mind taking my time.

[colind321]

I have put down several decks in the life of my present home and have used nails each time. So far have shyed away from nail guns for decking. Pre drill and nail is my opinion, does not take long if you have a couple of people. Finish looks great, well thats my opinion. Use a string line to ensure that the nails are in a straight line. Hope this helps. :2tsup:

regards

colind123

[PRKLCD]

anyone recommend what type of nail going into TP?

[dazzler]

Pre drill and then use galvanised dome headed twist nails, sometimes called 'Timberlok' twist nails.

Like this;

66985

Pre drill the shank size through the timber, drive them home level with the surface of the board. They WONT pull out :2tsup:.

[UteMad]

Do which ever you prefer but as to the photo's i will leave it to you to tell me which ones are screwed as i think up close screws loo better but overall they aren't noticed...

http://i91.photobucket.com/albums/k287/utemad/home-1.jpg

http://i91.photobucket.com/albums/k287/utemad/woodwork-3.jpg

http://i91.photobucket.com/albums/k287/utemad/beareronstirrup-7Small.jpg

http://i91.photobucket.com/albums/k287/utemad/spandeckmerbau-5.jpg

The top one is nailed with 65mm titadeck galv nails the rest are screwed with stainless 50mm type 17 sq drive counter sunk screws ... Not trim heads


cheers utemad

[dazzler]

I am interested in the reasons for screwing any deck, other than timber to steel :?.

[China]

I use a MAX CN565 coil nailer it has has driven thousands of nails never had a problem with it what are the bad thing youv'e heard about nail guns, most likely operater missuse

[PRKLCD]

I use a MAX CN565 coil nailer it has has driven thousands of nails never had a problem with it what are the bad thing youv'e heard about nail guns, most likely operater missuse

Without a dobut :)

[Dermot]

I've been using Deklok hidden fasteners for the last couple of years with great results- no visible nails, standard gaps, almost impossible for boards to lift. The new version (I think they're called stealth) are available through Tymlock in queanbeyan

[UteMad]

I am interested in the reasons for screwing any deck, other than timber to steel :?.

Better appearance
No popped nails
boards don't lift up off the joists
Can remove boards for access to plumbing etc below deck or if you damage one
Flush or sunken finish versus the raised head or a dome nail

Cheers utemad

[UteMad]

I've been using Deklok hidden fasteners for the last couple of years with great results- no visible nails, standard gaps, almost impossible for boards to lift. The new version (I think they're called stealth) are available through Tymlock in queanbeyan


What do you do in regards to the variation in board width which is up to 3mm... Are you doing this for yourself or customers? If for customers how do you compete in a market that is flooded with bodgy trades using the fastenings

cheers utemad

[Dermot]

These are jobs for customers- to whom it has been explained that the finer finish entails extra work. I haven't had too much trouble with varying timber widths and if I did I would have picked it up by measuring and adjusting every 5 or 6 lines -leaving one end not as fully embedded as the other- though this hasn't been necessary so far using TP, merbau,mixed reds or recycled black butt.

[UteMad]

These are jobs for customers- to whom it has been explained that the finer finish entails extra work. I haven't had too much trouble with varying timber widths and if I did I would have picked it up by measuring and adjusting every 5 or 6 lines -leaving one end not as fully embedded as the other- though this hasn't been necessary so far using TP, merbau,mixed reds or recycled black butt.


Just curious ...would a treated pine customer go for the hidden deck fixings over say hardwood and some sort of top fixing at a similar end cost? Seeing as treated decking is a base level product for a base level consumer

The board width i was referring to is when the deck is wide with end to end joins and discrepency in board width..


cheers utemad

[dazzler]

Better appearance
No popped nails
boards don't lift up off the joists
Can remove boards for access to plumbing etc below deck or if you damage one
Flush or sunken finish versus the raised head or a dome nail

Cheers utemad

I get the no popped nails, however I havent come across this with twist nails, removal of boards for access is definately an advantage where required, but I dont get the better appearance or the flush etc.

A domed twist nail has a 3mm head and can easily be sunk flush whilst the screw heads are at least twice as wide and far more noticeable.

Each to his own taste I imagine :)

cheers

dazzler

[PRKLCD]

Hi everyone,

I have been doing lots of research since my first post.

I actually live arcoss the road from a new display village and I often walk up there to get ideas for decks - this is where I first noticed screws being used for decks. I have now worked out that all the decks where built using 14g screws for some reason - and hence my comment in my orginal post about me not liking them( they were just too big)- it wasn't till today that I actually saw the head of the 10g and I must say that I like them!

So anyway I think I am going to go screws.

A few questions tho.

I still need to countersink with a carbitool (spelling) do I need to the boards and the joists? or just the decking boards?

Margent Mart has "topfix" SS 10g 50mm type 17 screws for $195 per 1000. Has anyone used this brand? and is that a good proce - what would you recommened I pay?

I rang a building surply shop this afternoon and the guy was telling me that SS screws would lose clour (look like rust) beacuse of the merbu??? is this correct? he told me to use galv screws which are a LOT cheaper!

Will take more photos of the deck tomorrow - almost ready for the boards!:2tsup:

[dazzler]

I wonder if they are using those screws with the driver that is at waist height so the screwer doesnt have to bend down to fix them making the process much quicker than nailing them. Dont know what they are called but they are in a few of the yank building mags.

[Burnsy]

I wonder if they are using those screws with the driver that is at waist height so the screwer doesnt have to bend down to fix them making the process much quicker than nailing them. Dont know what they are called but they are in a few of the yank building mags.
They might seem like a good idea Dazzler but to pull boards in tight to keep even spacing, keep your screws lined up and at even spacing as well I think you are better off down on your knees. I think the waist high things would only be good for final screwing off if you had already pinned the whole deck using intermitently spaced screws on your hands and knees.

I find the most enjoyable decks to screw or nail down are those that you can stand in front of the next board and push it back in as you fasten it.

[Burnsy]

I still need to countersink with a carbitool (spelling) do I need to the boards and the joists? or just the decking boards?

I rang a building surply shop this afternoon and the guy was telling me that SS screws would lose clour (look like rust) beacuse of the merbu??? is this correct? he told me to use galv screws which are a LOT cheaper!


Only predrill through the board, the screws will drive into the TP joists without a problem, predrilling a TP joist will reduce the effectiveness of the screw.

If the merebu is going to discolour the stainless it will do it to galv too. Spend the bit extra and go stainless, you won't be sorry, but you will be when the galv start to rust where the driver has chipped off the galv.

[manoftalent]

yep I agree with Burnsy, and if you do a good job, most likely ppl are gonna say what beautiful timber, doesnt it look good yadda yadda yadda ....only an experianced woody is gonna say .....soooo ya went SS huh.....:;......

[Chumley]

Margent Mart has "topfix" SS 10g 50mm type 17 screws for $195 per 1000. Has anyone used this brand? and is that a good proce - what would you recommened I pay?

I wouldn't use 50mm screws - the old rule of thumb is the screw should penetrate at least twice the width of whatever you're fixing, so with tp (22mm thick - at least mine was) you need screws around 65mm long.

This is one instance where you should forget magnet mart or bunnings - go to a supplier like http://elraco.com.au - they'll have the screws on your doorstep in a couple of days. It'll cost a little bit more than the 50mm screws, but it's not much, and if you're going to the trouble to build a deck you may as well do it right.

Oh, by the way, definitely go stainless steel. You can have a good looking result with better components (even though some will think of it as base level).

Cheers,
Adam

[Waldo]

:G'day PRKLCD,

You're asking the same question I asked a few weeks back, have a look at this link. http://www.woodworkforums.com/showthread.php?t=47415&page=2 and post #30 with suppliers over on page 3. :2tsup:

[sports fan]

as i think utemad said if its your own place definatly use s/s square drive screws for hardwood decking

i dont know why your worried about the look of screw heads when you have a massive a/c unit in the middle of ya roof?!

[PRKLCD]

I wouldn't use 50mm screws - the old rule of thumb is the screw should penetrate at least twice the width of whatever you're fixing, so with tp (22mm thick - at least mine was) you need screws around 65mm long.

This is one instance where you should forget magnet mart or bunnings - go to a supplier like http://elraco.com.au - they'll have the screws on your doorstep in a couple of days. It'll cost a little bit more than the 50mm screws, but it's not much, and if you're going to the trouble to build a deck you may as well do it right.

Oh, by the way, definitely go stainless steel. You can have a good looking result with better components (even though some will think of it as base level).

Cheers,
Adam

Cheers adam,

I will look at the 65mm screws now. I know you said to stay clear of MM. put I do have friend who can get me a good staff discount on them - should I still aviod that brand (topfix)?

Also, I have been reading that I shouldn't put all the screws in a straight line due to the risk of the joist spliting? what are peoples thoughts.

[Chumley]

Cheers adam,

I will look at the 65mm screws now. I know you said to stay clear of MM. put I do have friend who can get me a good staff discount on them - should I still aviod that brand?

No, nothing wrong with the brand (or even MM or Bngs) -- its just that they only stock them in bags of 50 or 100 which work out to be much more expensive than buying them by the 1000.

Cheers,
Adam

[pharmaboy2]

I wouldn't use 50mm screws - the old rule of thumb is the screw should penetrate at least twice the width of whatever you're fixing, so with tp (22mm thick - at least mine was) you need screws around 65mm long.


Adam

can I swear here?//??/ - bloody hell - a 65mm SCREW!!!! iahve never even heard of someone using a 75mm nail on this forum - not even sure if a decking nail exists that long, and the holdinjg power of a screw is at least double that of a gal nail - there was a post a copuple of years ago on nail holding power - ring versus screw shank etc and a study put out by one of the timber organisations - and screws were multiple times more effective than the longest compared nail of any type.

maybe a 50mm screw might pull out of green 140/25mm wide boards - but TP is kiln dried and 90mm - IMO 65mm simply gives you a a sore back, trigger finger, and more snapped screws.

[Burnsy]

Also, I have been reading that I shouldn't put all the screws in a straight line due to the risk of the joist spliting? what are peoples thoughts.

Won't happen with the TP joists you have so don't worry about it. Usually only required for nailing into old dry hardwood.

[Gaza]

can I swear here?//??/ - bloody hell - a 65mm SCREW!!!! iahve never even heard of someone using a 75mm nail on this forum - not even sure if a decking nail exists that long, and the holdinjg power of a screw is at least double that of a gal nail - there was a post a copuple of years ago on nail holding power - ring versus screw shank etc and a study put out by one of the timber organisations - and screws were multiple times more effective than the longest compared nail of any type.

maybe a 50mm screw might pull out of green 140/25mm wide boards - but TP is kiln dried and 90mm - IMO 65mm simply gives you a a sore back, trigger finger, and more snapped screws.

that study was conducted by timber qld.

http://www.timber.org.au/resources/Residential%20Timber%20Decking%20Nail%20Trial...

should be noted that the screws used these days have developed over the last few years from when the test was done.

[Chumley]

can I swear here?//??/ - bloody hell - a 65mm SCREW!!!! iahve never even heard of someone using a 75mm nail on this forum - not even sure if a decking nail exists that long, and the holdinjg power of a screw is at least double that of a gal nail - there was a post a copuple of years ago on nail holding power - ring versus screw shank etc and a study put out by one of the timber organisations - and screws were multiple times more effective than the longest compared nail of any type.

maybe a 50mm screw might pull out of green 140/25mm wide boards - but TP is kiln dried and 90mm - IMO 65mm simply gives you a a sore back, trigger finger, and more snapped screws.

Pharmaboy2, you can swear as much as you like - it's very Australian :D Not too sure where the 75mm nail comes in - we were talking about screws. And you are welcome to your opinion. For my current project, a gazebo, I have put in about 200 65mm SS type 17 screws (so far) to hold together the bearers/joists, frames and roofing - haven't got a sore back (well not from screwing), trigger finger is fine, and I've only snapped one screw - and that was because I was trying to drive it through another screw. I've got about 580 screws to put in the flooring - they will all be 65mm.

I did quite a bit of research before starting, and after assessing all the advice from this forum and from the chippies/builders at work, I wouldn't use anything shorter than 65mm on 22mm flooring. It's true that materials and techniques do improve - I still think the old rules-of-thumbs have merit.

Gaza, the link you posted doesn't work for me.

Cheers,
Adam

[pharmaboy2]

new link

http://www.timber.org.au/menu.asp?id=140

download the pdf file

the 50mm ss screw had 5 times the amount of holding power in hw compared to a std flat gal machine driven for instance - 1.1kn is considered adequate, a ss 50mm screw achives over 10kn in HW, probably half that in soft wood or 5 times minimum! (HW and SW relates to the joist material)

for decking type, its the head type that counts for withdrawal when looking at TP, as its most likely that will be the failure point - so bullet heads in 2.3 would be very much marginal in holding power for TP deck.

BTW you cant do much harm by going 65mm, but if 50mm out performs most other fasteners by a factor of 5, its sort of hard to justify I think....... ;)

[UteMad]

Each to there own as for screws verse nails... When i get round to it i'll post the photo's i took today of a deck done at the end of december 07 so 2 months old ..its merbau boards with merbau joists and nailed with a screw shank stainless nail put in with a duofast coil gun... The photo's speak for themselves...

Stay away from the extension screw drivers that put the screws in off a strip .. They self drill and self countersink ... It doesn't work with hardwood..they split the boards at best and don't have enough strength to drive flat.. The company rep spent a good 30 minutes trying to prove me wrong only to say in the end that american decking must be softer..

Stay away from the Gal screw as most aren't really heavily galvenised and rust pretty quick aswell as having thin shanks and snapping..
The discolouration from the merbau on the heads is the boards leaching and they'l do that on anything for the initial period..

If you buy a carbitool counter sink and pilot it'll counter sink and pilot the board in one... You set the drill bit to just pilot the board when the sink is at the right depth..

50mm screws is plenty for 19mm decking into treated joists

190 buck per thousand aint cheap...

A good retail price is closer to 150 per thousand

I'll let the screw Vs Nails debate roll on ... But i think i will opt out as it bores me to no end LOL

cheers utemad

[PRKLCD]

Hey has anyone seen or heard about gold 10g screws before? :rolleyes:

[Burnsy]

Hey has anyone seen or heard about gold 10g screws before? :rolleyes:

:oo:No, but my first thought is yuck:oo:

[PRKLCD]

:oo:No, but my first thought is yuck:oo:

That's what I thought - but I was talking to a builder at the gym and he reckons wit Merbau it looks really good.

I will see if I can get some gold ones today to do a test run. Will let people know what it's like

EDIT:ok gold ones are just zinc coated screws - no good for decks - my bad

[UteMad]

Was just about to post that... Internal use only.. Must be some builder hey!

cheers utemad

[PRKLCD]

Was just about to post that... Internal use only.. Must be some builder hey!

cheers utemad

Yeah he is a 1st year apprietence - glad they aren't building my deck :oo:

[Bloss]

Just my two-bob's worth - 50mm for screws into TP is fine and 65mm would be overkill on cost and utility ground.

Although nails can be re-punched a tighten up of the screws after a bit of time with shrinkage etc will give a much better technical result than nails if you are OK with the extra initial cost and time to put them in. You see the holes or the heads if they are the domed type with nails, and the heads with screws so that is an aesthetic issue only.

If time is your concern then nail guns work OK (which is why builders tend to use them), but with almost all hardwoods you will get splitting. All ends should be pre-drilled in any case. It is not uncommon to see untreated nails used from guns and they will fail rapidly.

For TP you should use those fasteners especially coated for use with TP (not gal or gold zinc which corrode rapidly) or SS as you are leaning towards.

Pre-drilling need only be through the boards not into the TP underfloor.

[PRKLCD]

Thanks for everyones help with this - it's been great.

I ordered the SS screws today, all ready for the weekend. I am going to use 5mm spacing between the boards.

I am interested in finding out about this "5th board down" approach - I have had a search but can't find anthing.

Any tips for ensuring the screws are in a straight line?

More Pics tomorrow!

[Waldo]

Any tips for ensuring the screws are in a straight line?

More Pics tomorrow!

A string line with a nail at the end of each joist and progressively move the string as you go along.

[Spider Webb]

As Waldo said PRKLCD, maybe to save a little bit of time if you are screwing, is to use a string line every 3 or 4th joist as in the picture. you just have to pull the string down at each new board and come back later to infill the joists you missed with a screwed string line. Depending on how straight your boards are, the more space you can have between initial screws.
You won't be disappointed with the stainless, for a few extra dollars i think they give a better look.
Hope your back and knees are ok though, takes a lot out of them. I used knee pads which helped alot.
I didn't use the 5th board method, but i think the main aim is so you can clamp 5 all together and screw down, then measure out 1 board width then clamp another 5 and so on, then fill in the missing boards. Don't quote me on it, i've only just screwed my first deck myself.

Good Luck

Stew

[Spider Webb]

Just remembered...... Make sure your pilot hole for the merbau is the same size or a fraction bigger then the screw size. Snapped heads will be common otherwise and the remaining threads are a bitch to get out without ripping the crap out of your board.
I snapped too many before realising if your board isn't flat on the joist you are trying to pull the two together with your little thread on your screw and its too much for it to handle. ($40 wasted on a 3.2 Carbitool)
Board pulls down fine with a coutersink a little smaller than screw head diameter, and let the screw do the rest... :U

[UteMad]

. ($40 wasted on a 3.2 Carbitool)
:U[/quote]


How so??

Cheers utemad

[Spider Webb]

I bought the 3.2 from reading one of the posts here which said would be suitable for a 10g screw. I found the 3.2 pilot was too small and was subsequently snapping heads off cause if the board wasn't flat on the joist, the screw would thread (bout5mm dia) the board then thread the joist then when trying to pull the two together with the thread, it was too much for the screw. I hope i didn't confuse more than explain.
It won't be a total waste, it will sit on the bench for a while but i'm sure the wife has another project just around the corner where i can use it again......

Stew

[UteMad]

I bought the 3.2 from reading one of the posts here which said would be suitable for a 10g screw. I found the 3.2 pilot was too small and was subsequently snapping heads off cause if the board wasn't flat on the joist, the screw would thread (bout5mm dia) the board then thread the joist then when trying to pull the two together with the thread, it was too much for the screw. I hope i didn't confuse more than explain.
It won't be a total waste, it will sit on the bench for a while but i'm sure the wife has another project just around the corner where i can use it again......

Stew

Hi Stew

The 3.2 is the size for 10G screws. My offsider bought the 8G one by mistake once for a job which is too small and suffers the complaints you listed


Fistly you set the pilot bit to a depth so when the countersink just reaches the point where the screw would be flush the pilot just breaks through the board..
Before laying the deck check that the tops of the joists are reasonably flat and if there are any major discrepancies like more than 2-3mm plane them or pack them..
When buying the screws make sure they are true 10G type 17 screws and not stainless 8-10G pin pointed chipboard variety that have a thinner shaft and will snap if over tightened
The best tool to put them in is an impact driver from our experience as you can hit the board and then fine tune if necessary.. Roofing guns do a rather average job as they don't have the torque to add the extra bit nor do power drills..
If the boards hair up around the head the countersink is to small or too shallow.
If your snapping screws then you most likely bought the wrong ones or like you said the joists weren't flat so the screws were under enormous strain trying to pull hardood down a few mm over only 450mm something that a nail would never have a hope of achieving anyway.. We would shatter probably 1 maybe 2 driver bits on an average deck just from the impact driver and possibly break 1 or 2 screws but these would be from hitting another fixing in the joist like a gun nail or bolt and not just into normal pine timber
They are a great countersink and i hope you find some use for it in the future. If you break the drill bit its a standard 1/8 bit which makes replacement easy..

I hope your deck came up a treat

cheers utemad

[UteMad]

I looked at your photo above.. Your boards are they 22mm thick? i.e
140 x 22 Merbau ? If so a 10G screw would be a minimum fixing for the job we'd have used a 14G either gal or stainless bugel screw for this size board and put it in with a 240Volt rattle gun and obviously a different pilot and countersink to suit .. 10G is a tad under done for this size board although others would disagree.. We use the 50mm screws for 80 x 19 merbau ..
You'd have better luck winning lotto than bending one of those boards down with a 50mm screw..No offense intended

I hope your deck is finished and your happily enjoying the fruits of your labour

cheers utemad

[Spider Webb]

Thanks for the info Utemad, yes 140*22 they are. Maybe i should of asked the question about fixings rather than stalk this site before i started like i did, but as you said everyone has their own opinion.
I used the 10g t17 deck screw from Chloe fasteners so i presume they are good quality, i just found i hardly snapped a screw using the bigger pilot. The boards came down ok using the head of the screw (If there was cupping it might of been a different story). I snapped about 6 out of the first 200 i put in using the 3.2. It is a great tool, worked a treat and a good time saver but for me, i would of liked a bigger one. I was using a Hilti b/drill so that might of been my problem also.
Just about finished now, just tidying up side boards and the oiling to go. The wife is happy with the product so far, so all is good!!
This is a great website, i stay on here far too long reading everyone's ideas, tips and problems so if anyone gets some help from this, kudos to you and i.

Sorry for the hijack PRKLCD, Good luck this weekend.
Stew

[UteMad]

Hi Spider webb

Its not a bad forum hey.. If everyone pools a bit of info one day we are all bound to get some helpful tips when the time arises.. Good to see your deck is flying along.. Haven't heard of the screw brand your using but that means nothing as there are so many out there and most prob come from the same place anyway

cheers utemad

[PRKLCD]

Ok guys.

I got the screws today ( see photo below ). I was originally looking at screws at my local Mitre 10 (topfix I think) and the screw heads where a lot smaller than these ones ( both say 10g ) the ones below are from a specialist fastener shop. Maybe the other ones were trim heads?? I am not sure.

I have also attached a photo of the carb-i-tool if anyone is interested.
<O:p
I will practice with the screws this week and I will start the decking over the weekend ( thanks to utemad for some very helpful tips )
<O:p
What do people use for mapping out the best place for decking joins? I know that the consensus is for them to be spread all over – I do want to leave the line of slight from the back door relatively free of joins ( is this a good idea?) I just plan on using excel to get an idea on how I will stagger the boards.
<O:p
Thanks again for all the help – I will make sure I give back to the forums once my deck is done!!

[UteMad]

Ok guys.

I got the screws today ( see photo below ). I was originally looking at screws at my local Mitre 10 (topfix I think) and the screw heads where a lot smaller than these ones ( both say 10g ) the ones below are from a specialist fastener shop. Maybe the other ones were trim heads?? I am not sure.

I have also attached a photo of the carb-i-tool if anyone is interested.
<O:p
I will practice with the screws this week and I will start the decking over the weekend ( thanks to utemad for some very helpful tips )
<O:p
What do people use for mapping out the best place for decking joins? I know that the consensus is for them to be spread all over – I do want to leave the line of slight from the back door relatively free of joins ( is this a good idea?) I just plan on using excel to get an idea on how I will stagger the boards.
<O:p
Thanks again for all the help – I will make sure I give back to the forums once my deck is done!!


Mate you got the right countersink for the job and it will do you proud.. Check on a sample as the screws you have say 10 - 12 G so just check the head is 10G which is easy all you do is countersink a hole and go in too far , the head should be the same dia as the sink...

As far as mapping boards its fine to keep joins away from the door it will just put more elsewhere.. the aim is to not have 2 rows of boards next to each other joining on the same joist this is a no no try for 2 or preferabley 4 joists til you join on the same joist.. Bugger excel your making life too hard.. If your using merbau it will come generally in 5 board bundles ... sort your bundles into matched lengths so you know what you have..

Carry the whole bundle of long boards down and put it on the deck either stick one down each end or put them all flush to one end and say 5 boards apart .. get another bundle of a shorter lerngth and do the same..
figure out whether you have a bundle that will do the remainder of the length to the other end of the deck.. Keep repeating this and you'll have it mapped nice in an hour.. Cut your end joins neat and its done

cheers utemad

[PRKLCD]

Ok the carbi tool is unreal! well worth the money!

Quick question - when butt joining merbau - do you need to leave a spacing or is it flush???

[Waldo]

Leave a spacing, of a couple of mm to allow for seasonal movement. :2tsup:

[PRKLCD]

Leave a spacing, of a couple of mm to allow for seasonal movement. :2tsup:

2mm enough?

[UteMad]

3mm is better allows the boards to move and small rubbish to fall through and not just build up in the cracks plus you can get discrepancy with board width.the gap also lets the subfloor ventilate on decks low to the ground.. if the deck is really low 4mm is good. this gap is for 70 and 90mm boards up it to 5 - 6mm for 6inch

cheers utemad