Decking... agh! help!

[5 shires]

Hi Guys

 

I've got a few jobs now where a couple of customers want some decking built, I understand whats generally got to be done and I have done one or two small areas before..... but my most recent quote is for 54m2 of decking at about 300mm high.

Now I'm finding all sorts of information on posts and supports it looks like a post every 1m down the length and at every 500mm across the width.. this calculates to a total of 133 post for 54m2 which means not only 133 post holes to be dug but probably also knocking on for £2000 in postcrete!?

SURELY THIS CANNOT BE RIGHT!?

 

Any advice? what do you guys do?

or is there a book you can recommend that will help me out here?

 

Many thanks in advance, Phil.

 

Small amount of postcrete.....half solid 4" concrete block..save on digging out lots of ground to required depth,save on postcrete and supports sitting on half concrete block is more then adaquite for decking supports.

[kevinjohnsonmbe]

Think it's actual planning permission, not just building regs. Under 300mm and it's not a problem

 

 

👍🏻 I was just shooting from memory, I thought there was some Reg that applied. I remember a cafe / diner local to us that put in a massive deck and then had to do retrospective application or rip it out. All got a bit messy.

[dumper]

Posts at 1.2 m centres 150 x 75 MM bearers at 1.2 m joists at 400mm centres running at 90 to bearers posts no smaller than 100 x 100 class four timber , better still use concrete blocks to support bearers with slate to act as damp proofing 600 MM centres on joists should only be used if deck boards are thicker than 25mm

[muttley9050]

I reckon most of you guys over spec your decking support.

Average rule of thumb is

A joist needs to be 1" per 2 foot of span plus 1".

So 10 ft span needs 6x2 joists. 20 ft span needs 6x2 plus 1 support purlin mid span.

So decking which comes 20 ft or 6m from wall I would use 6x2 joist with a 4 X2 wall plate fixed to wall, support mid span either post or purlin and wall or support at far end.

18 or 20mm boards need 400 centres and 22 abd 25mm boards need 600 centres.

Build quite a lot 8m diameter round yurt floors for school classrooms (not decking but ply and carpet or hardwood) and domestic decks.

8m yurt floors I use 6x2 purlins at 2m centres with supports every 3m max with 4 x 2 as top joists.

Could use bigger purlins and loose mid supports but this brings it off the ground too high.

[simonm]

Everyone's got their own way of doing it like owt else, our own way is almost always better than other peoples

A long as its solid and looks good does it matter?

[5 shires]

Everyone's got their own way of doing it like owt else, our own way is almost always better than other peoples

A long as its solid and looks good does it matter?

 

Correct

[muttley9050]

Everyone's got their own way of doing it like owt else, our own way is almost always better than other peoples

A long as its solid and looks good does it matter?

 

Well said

But over specking eats the profit.

[Mull]

Well said

But over specking eats the profit.

 

 

If client accepts your overspec, how does that eat your profit?

[donnk]

postcrete is a rip off.

 

ton bag of ballast @ £40

10 bags of cement @ £3 ea

 

You can either do a pad, saves wood uses more conc. Or bed the post less conc more wood wood rots.

 

get the longest 5x5 beam put a post at each end and one in the middle.

 

If its all going to be boxed in you can always use conc posts and chop them in half.

 

It's carry people not cars at the end of the day.

[muttley9050]

If client accepts your overspec, how does that eat your profit?

Strange question! If you charge £1000 for a job and spend £400 you make more money than if you spent £500. Also over spec means more labour costs.

Client isn't usually interested in spec. Just finished product and price. I charge less and make more than the over spec man.