Any builders/landscapers on here?

[Adam]

I'm building a deck and need some design input. The deck is approx 4.8m x 4.8m. The decking is macrocarpa (150mm x 32mm) and I've order enough 100 x 50mm joists for 450mm centres. I need to spec out the bearers. How big do they need to be and what range should the span be? The bearers will be at ground level.

Cheers

Adam.

[duncan]

This will probably answer your question.

disclaimer: I'm not a builder, and the only 2 decks I've ever built were over-engineered. The first one was 3M above ground & I managed to source some 300x300 posts so it was more solid than the house it was bolted to.

The other thing that might be useful is checking wether your local council may have regulations for size etc

[Mark Vuleta]

edited, wrong. too late at night

[Adam]

Thanks guys.

mark, so if I dupouble up the bearers, I only need 4 rows?

[Mark Vuleta]

edited, wrong.

[Adam]

Yep, 4 rows of bearers with 5 rows of joists above them. Min. thickness for any bearer is 75mm but it is generally cleaper to double a 150 x 50 (to make it a 150 x 100) than try & find a H3 150 x 75.

Thanks. 5 rows of joists? I was planning on 14?

[Mark Vuleta]

(Edited again & again, must have been too late at night: Decks are supposed to be designed to a 2kpa floor load, I origionally calculated at 1.5kpa)

(taken from NZS 3604:1999, this standard has been revised since my copy but this aspect (timber loadings) haven't changed from my understanding)

For 100 x 50 floor joists @ 450 centers, max span of joists is 1.40m.

Therefor, suggest 5 rows of 150 x 100 bearers at 1.2m centers (perimeter & intermediate spacings)

150 x 50 treated timber is generally cheaper than 75mm thick timber, suggest double 150 x 50 to give 150 x 100 bearer, 5 rows at 1.2m centers (perimter & intermediate spacing) with 125 x 125 timber piles at 1.6 centers along the bearers i.e 4 piles per bearer, total of 20.

With the bearers being at or near ground level, stainless steel fixings will be required.

For a deck, floor load only, pile footing support only needs to be min. 200mm square or 230 dia.

[RPM]

This will probably answer your question.

disclaimer: I'm not a builder, and the only 2 decks I've ever built were over-engineered. The first one was 3M above ground & I managed to source some 300x300 posts so it was more solid than the house it was bolted to.

The other thing that might be useful is checking wether your local council may have regulations for size etc

Yes, check with council, visited recently as deck is on my to-do list. Max size here to build without a consent/permit is 20 square metres and no higher than 1m off ground and 1m away from any boundries. Even without a consent/permit it still has to be built to building code standards so keep that in mind if your selling soon or have nosey neighbours that are liable to interfere. Council guy here in Napier was very friendly and helpful.
http://www.legislation.govt.nz/regul...DLM162576.html standards

http://www.legislation.govt.nz/act/p...DLM309339.html exempt work

[Adam]

Thanks guys

I have already looked into the regs and ihave factored in most things I hope

[Adam]

here is a crude picture of my plan

deck.pdf

deck.pdf

[duncan]

here is a crude picture of my plan

deck.pdf

deck.pdf

looks fine to me..

[Adam]

OK, here are some work in progress photos. It's a case of slow but steady progress at present as I never seem to get a long run at it.

So far I have put down the Macrocarpa sleeper lawn edges and shifted 5 cubic metres of soil from the drive, and levelled this off. I installed the sprinkler system but time pressures meant someone else laid the turf. (Not sure they did as good a job as I would've done but I want to get everything finished before I leave for the UK in two weeks).

#1 - new turf


The deck is progressing slowly

#2 - The AWESOME saw


#3 - The Workshop


#4 - Hard at work (self portrait)


#5 - Where else do you store nails? (Self Portrait)


#6 - Details matter


#7 - Two bearers in place, two to go!

[rjd]

Lookin good!

Leme know if you need a hand

[randomguy]

Lookin good!

Leme know if you need a hand

the saw would be handy for that kinda thing

[Adam]

the saw would be handy for that kinda thing

Indeed. I'm very paranoid about unplugging it etc when not being used, as small children can be inquisitive...

[Jos]

Jeepers that would be terrible!!!


Looking good though Adam, you have skills!

[Adam]

A couple more showing progress. I got the last two bearings levelled and cemented in on Friday night, and then squeezed in an hour on the weedmatting on Saturday (in between golf and going out for a Thai feed). After more golf, and junior golf, I managed a few hours run at it and got all the joists in place. It might yet be finished before the UK trip..!

[duncan]

It might yet be finished before the UK trip..!

nice - Just a thought, you do realise there's going to be about 1200 nails holding down the decking? (that also need to be punched below the surface)

but then there's these new things called "nailguns" around that make things a bit quicker...

[Adam]

nice - Just a thought, you do realise there's going to be about 1200 nails holding down the decking? (that also need to be punched below the surface)

but then there's these new things called "nailguns" around that make things a bit quicker...

Yes, I have a big tun of nails waiting for me...

There are 10 joists and about 35 boards so it should "only" be 700 or so...

[Adam]

I've been researching punching the nails and advice is conflicting. It appears that twist nails are not designed to be punched. Anyone confirm this?

[Adam]

I've made a bit more progress over the last two nights. All the joists are fixed in place (with Z nails) and I've made the "frame around three sides of the decktop. Finally, I've cut almost half of the boards to length but I still have to drill/nail them into place. Hopefully I'll be ready to drill and nail them over the weekend!

[Kawaka]

Looks like pine decking, why drill.
There is no need to punch nails on decks, just drive them down flush.

[Adam]

Looks like pine decking, why drill.
There is no need to punch nails on decks, just drive them down flush.

Thanks. It's Macrocarpa decking.

[Russ]

I had a deck made - I got them to use stainless steel screws to hold the decking down, they used a screw-gun.