Staggering & laying out spotted gum boards...

Originally Posted by Savvas

On the question of Spotted Gum & butt joints, the supplier tells me that the boards are thoroughly kiln dried and shouldn't need a gap at the butt joints - that is, they won't move lengthwise! Does this fit with the experiences of others who have used Spotted Gum? I plan to leave a 4mm gap between adjacent boards and will be using the ceramic coated Razor screws.

It is normal to butt-join the ends of any timber as expansion and contraction is greatest across the grain rather than with it. Four mm gap between boards is fine but I would go more if there is any chance of ground moisture issues.

Thanks for the response phild01 - appreciate it. The deck is entirely underneath a covered pergola and - apart from a few windblown drops - is unlikely to see much moisture. It's built over a concrete slab and any moisture present underneath will be very occasional - maybe from a spilt watering can etc. So I reckon I'll stick with the 4mm gap as it works well with the dimensions of the deck.

Re gap; I would listen to the experts (i.e. Phil) and if you did any research it would tell you are wrong.

Stagger without having adjacent boards butting in the same joist space preferably for the next two boards.

Butt them as tight and square as you can.

I just re-stacked all the boards roughly based on length, then just started laying the boards using the fifth board method.
Measured and laid every fifth board, when filling in between make sure butt joins are somewhat random, with the boards sorted by length it is easy to optimise their use and minimise offcuts.

Utilising a "pattern" is going to depend on what lengths you are supplied, any pattern repeated often enough will look like a pattern, I would try to make it as random as possible.

Thanks Bushy - advice on the staggering sounds good. Not sure on what point you are indicating I'm in the wrong (ie; with reference to Phil's advice). He was referring to a situation where there's some possibility of 'ground moisture issues' I believe. There are none applying in my deck's situation...

Thanks Droog - encouraging advice. After lots of 'standing and looking' sessions I've decided to abandon any idea of working out a 'pattern' based on the lengths I have to hand. I've roughly sorted out the lengths and If I follow any sort of repetitive pattern I think I'm going to see a lot of waste. A truly 'random' approach will I think be much easier and will probably allow me to concentrate a bit more on dealing with the quite large number of 'bent' boards I've encountered when sorting them out. I've now watched a couple of videos on youtube and the 'every fifth board' approach really seems to make sense. I am worried about a couple of the joists which are not as straight as they should be so I'm going to have to try and avoid having joints on them. I'm pre-oiling the boards back, front & sides, so will need to get all that does before I start laying.

Hi Folks,

I want to offer a belated 'big, big thanks!!!' to everyone who provided me with both general & specific advice when I was commencing the build of my new deck & pergola! All advice received was both extremely valuable as well as morale boosting - apart from the general craziness of embarking on a course of DIY planning & owner-contracted renovations 29 years ago, this has been the biggest project I've undertaken!


In particular I appreciated the tips given regarding the '5-board' method, use of heat-treated, ceramic-coated 60mm Razr screws (not one broken!) and finishing with Feast-Watson wood oil. I'm very pleased with the result! Although I see little mistakes and blues everywhere I look, I'm the only one who does see them! Wife is very happy which is what it's (mostly) all about. ;-)


One product I can really recommend as invaluable to a novice deck builder was a box of 100 JambIt wooden wedges. Along with some small plastic 5mm spacers, these wooden wedges proved essential in coaxing the 86x19 Spotted Gum I used into some semblance of straightness & alignment! Worth every penny! Needless to say, most of the plastic deck-building crap that I bought when I first went to Bunners proved useless!


Here are a couple of pics of the final result - please ignore all the crappy 'furniture' - we were cleaning out the shed.


Thanks again all! Sam in Adelaide.

Looks great mate, deserve to have you're feet (foot) up.
Well done.