# Forum Home Renovation Stairs, Steps and Ramps  Footings and support for deck stairs

## Gado

My son and I have nearly finished building a great new deck and we really appreciate the wonderful information in these forums. You helpful people have given us the confidence to get plans through council and take on the project ourselves. A great experience, with only a few minor hiccups! 
To finish the job, we have bought a set of kit stairs made of treated pine, about 900 wide. The deck is 2m from the ground (11 treads). 
We plan to put a full width concrete pad, say 1100 x 500 at ground level to act as bottom step and secure the stringers and handrail post. We would prefer to use metal stirrups rather than sit the timber on the concrete. 
The stairs will have a timber handrail/balustrade attached to a 90 x 90 post at top, centre and bottom. The top post is full height from the ground (supporting a corner of the deck) and the centre post will be bolted to the stringers.  
At the bottom of the stairs, we will have the 90 x 90 posts as well as the stringers. I haven't been able to find a suitable stirrup for the stringers (45 thick and about 200 long at the base) - so here are the questions - 
1. Would it be OK to mount the stairs as follows - house and bolt the stringers 20mm into the bottom posts, chock the stairs in position, attach stirrups to the posts, then pour the concrete pad, so the stringers will be suspended a few mm clear of the pad? 
2. How deep should the concrete pad be, and does it need reo? 
3. Do these stairs need a threaded rod half way along to stop the stringers spreading? 
Thanks, Gado

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## intertd6

There is a standard for timber stair design & construction which I have not seen for a while but it exists, it gives details of tie rod sizes & spacings. For footing design I would go the minimum pad size for your foundation material which requires no reinforcement. 
regards inter

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## METRIX

Footing size should be around 300x300x300 minimum, but would be preferable match the size of your other footing specified in the plans as council may require them to all be the same. 
Best to ring the guys at the council quoting your DA and ask them if they have any special requirements so you make sure the hole is not too small when they come to do the final inspection. 
You wont require any reo in the hole just concrete is fine, and you can attach a L stirrup inside the stringer where the final post is and bolt through the whole lot, or put a HDG angle bracket at the bottom and bolt into the concrete pad. 
You are correct in propping the stair a few mm off the ground and pour concrete in around the stirrup base which will be sitting down in the hole, use regular concrete and not quickset. 
You will require threaded rod every 1300 of stringer length to stop spreading. 
You are best off to ring the council with these questions, they can be very helpful and this way you ensure your obiding by any special requirements they might have, so when the final is done there are no suprises.

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## Gado

Thank you for these helpful replies. Have been talking to council who have been helpful through planning and 2 inspections so far but I have only now been thinking of stair footing detail. 
Other post footings are 400 x 400 x 200 (council changed them from my proposed 300 x 300 x 300) so I guess they should be happy with 1100 x 500 x 200 deep for the bottom step. 
Good idea to bolt the stringers and handrail to a half stirrup - thanks Metrix Building.  
I think I'll put a threaded rod through the stringers and handrail posts at half way. It seems a common sense safety thing but hard to find specific recommendations - I'm surprised the manufacturer of the pre-fab stairs doesn't mention it. 
Cheers, Gado

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## Gado

> There is a standard for timber stair design & construction which I have not seen for a while but it exists, it gives details of tie rod sizes & spacings.  
> regards inter

  It would be nice if the standards were easier to access, I can't see why they need to make it so hard for people to work out what the rules are! With a bit of persistence, Google helped me find enough to go on - thanks inter 
Cheers, gado

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## intertd6

They are really easy to find when you work for a building company who has a membership with the Master Builders or HIA, just call their member technical service info  number & they fax through the relevant pages of the standards or BCA you require.
regards inter

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## Bloss

> It would be nice if the standards were easier to access, I can't see why they need to make it so hard for people to work out what the rules are! With a bit of persistence, Google helped me find enough to go on - thanks inter 
> Cheers, gado

  Regardless of how easy it might seem for some to get a copy, and one has only to read this forum to see that they are not actually all that easy to get access too - especially latest versions, IMO all standards should be free. The charges and fees were largely to offset publication costs - hard copy publication which rose every year and governments with 'user pays' decided costs should be passed through. Nowadays the real cost to produce and distribute PDFs is trivial. 
The work on the standards committees (all of them not just building) is 'donated' ie: by participation of the stakeholders in the various committees. There are costs of course, but because they are spread and it means the standards are then more likely to meet the needs of industry as well as the public good, then private sector and public sector contribute. Any sales money does not go back to those stakeholders although they do cover some costs of running the standards processes. 
But the principle ought to be that they should be given the widest possible access - to encourage the adoption of at least those minimums (as that's all they are). A number industries are now moving to make sure that 'best practice' or at least 'better practice' advice and information is also available so that those who wish to deliver a better than minimum required result can do so - they can usually charge a premium for that so long as the improvements above the base are measurable and there is a certification and trusted compliance program in place.

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