Stairs

[antman]

Hi all,
Are there any generally accepted standards for outdoor steps? I am about to build some onto my deck and would like to know of any things to avoid before starting! Any advice out there?
Cheers
Anthony

[Termite]

Ergonomic reccomended:- Rise 180mm. Tread 280mm. If tread too narrow you will be able to walk up it but you'll fall on your face going down.
Kind regards
Termite

[Gumpy]

Its been awhile since I have built an external stait but we would always use Merbu 300*45 from memory.

Trench the treads in 15mm and skew nail from the backs of the treads into the strings.

Put metal ties between the strings, use allthread or threaded rods.

The minimum GO was always 250mm plus 30mm for the nosing which works out to be as termite suggested.

Daniel

[antman]

Thanks for that.

Given a tread of 280mm, how wide could I make the tread? (Assuming the Merbu 300 X 45)

Cheers
Anthony

[Trav]

There is a great book by Alan Staines (?) I think called the timber decking manual. He goes through it in some detail. I reckon you should get that book, because it is more complex than it sounds. You need to think about the thickness and width of your timber for both the stringers and treads, especially as you will be notching out or trenching the stringers to put in your treads. At $30 bucks, it is money well spent.

I made 3 sets of stairs with treated pine as the stringers and spotted gum as the treads. My treads were 290 wide (3x90), with a rise of about 190 for each step (from memory). Stringers were something like 290x45 I think.

There is a strict formula that you should follow for the rise and run. Also, buy a rafters square, as it makes it heaps easier to figure out the angles.

The trickiest bit is actually fixing the stringers to the ground.

Good luck - sing out if you need more info.

Trav

[antman]

Hi Trav,
Thanks for your advice. I will have a look for the book. How have you fixed your stringers to the ground? Mine will go onto a concrete slab that already exists so I was thinking dyna bolts and some sort of hidden bracket but hadn't thought much more than that.
Cheers
Anthony

[Trav]

I used stirrups and fixed them into little concrete pads. Your suggestion is right - if you already have a slab, just get a bit of gal steel angle and bolt it to the stirrup and the ground. Too easy. Bunnings also have all sorts of brackets that you can use, but the cost mucho dinero.

Trav

[jackiew]

don't neglect to get all of your steps at the same spacing .... the human brain likes to extrapolate from previous experience ... if you step up x cm from ground to 1st step and x cm from 1st step to 2nd step then your brain will assume that the step from 2nd to 3rd will also be x cm ... if it isn't ( x+1 cm or x-1cm for example) then you ( or your litigation inclined visitors :eek: ) are more likely to have an accident than if the steps are equally spaced....

[antman]

Hi Jakiew,
I have to agree, nothing like that horrible sinking feeling when the step is not where you expect it. It seems to be worse when carrying that heavy and expensive load too. Can't understand why. :D

Given that observation, I will have to rethink the top step a little but no big dramas.

Thanks all for your feedback.
Anthony

[GeoffS]

A 'magic number' is normally used, the magic number being the rise x go.
In imperial measure the magic number was 66 - that is 6" rise by 11" go. That agrees pretty closely to 'termites' figures. A case where inches are easier to use, the figures being smaller.
7 x 9.5 is about as steep as you should go, 6 x 11 is very nice, almost lazy, and 5 x 13 can start to feel uncomfortable.
Cheers

[miked]

Gidday Antman,

This web site gives some good guidelines for stairs.

Cheers

http://www.greenhouse.gov.au/yourhome/technical/fs63_2.htm

[Theva]

Antman,

Alan’s decking book is good, available at Bunnies. It is good DIY guide

Few pointers:

Do not use single piece of timber as external tread, two of 150 is better.

Use galvanised or duragal angles to attach tread to stringers, preferably with roofing type screws.

Rise & going should be same for all steps including the one at ground level / bottom and top, the tip of the treads should be in line with the others (within a few mm max).

This is good link on terminology http://www.budgetstairs.com.au/bud2.html

Good luck.

Regards,

Theva

[antman]

Hi all, thanks for the replies so far.

I am wondering about the merits of housing the treads into the stringers, cutting a 'saw tooth' pattern into the stringers or using gal angle or brackets to attach the treads to the stringers.

Any ideas on any of those methods? Best result? Easiest to maufacture?

Thanks again,
Anthony

[duckman]

Hi all, thanks for the replies so far.

I am wondering about the merits of housing the treads into the stringers, cutting a 'saw tooth' pattern into the stringers or using gal angle or brackets to attach the treads to the stringers.

Any ideas on any of those methods? Best result? Easiest to maufacture?

Thanks again,
Anthony

Hi Antman,
Using gal angle is easier, faster, more forgiving (see end note) and should help to prolong the life of the stairs because you are minimising the number of 'water traps' in the structure.

Using two or even three narrow boards with a small gap between them is also preferable to using one wide board as treads, as the effects of 'cupping' are minimised and therefore the treads are less prone to holding water which can be both dangerous and lead to premature failure of the stair.

HTH,



End note:
Stairs can be difficult to get one's mind around for the keen amateur and tradesmen too if its been a while since the last flight of stairs was made. Using gal angle, you can set out your stair stingers, place the gal angles on the strings, have a really good look at it, seek a second opinion and do so without cutting anything or drilling any holes. Gives you more opportunities to get it right.

[Trav]

I wanted the hidden stringer look, so I cut a sawtooth pattern into the stringer and then cantilevered/overhung the treads by 100-150mm or something. Housing sounds like a pain in the ***** if you ask me. I looked at the brackets, but they are about ten bucks a throw in bunnies, so I gave it a miss and just cut out the sawtooth pattern. Worked a treat - eventually. It took me a while (three sets of stairs with three steaps on each set and one set more than 2m wide) and I had to fiddle a bit when I tried to attach them to the deck.

This was the trick for me - I used 190x45 treated pine for the joists and facia joist. As my rise for each step was 190, it didn't leave me much timber to screw into. So I had to add an extra bit of timber under the joist to give me that extra room to screw into. I've made it sound more confusing than it is, but it is something to think about.

Also, I agree with everyone above - make your treads out of a few narrow baord rather than one big wide one.

Trav

[julianx]

It's difficult to describe how to build a set of stairs with out diagrams and I'm hopless with computer pictures of any kind, heres an few tips though.

the formular for a perfect stair is 2 x the rise + the going = 600mm. this is based on the theory that it takes twice as much effort to lift your foot upwards as is does to move it forward and the average pace for and adult is 600 mm.
A flight of stairs shouldn't have any more than 14 treads without a landing

The standard size timber for stairs is 250 x 50 for both stringers and treads.

To prevent the tread from holding water make sure the sap wood is on the bottom so cupping will occur on the underside.

If you want the "hidden stringer" look you might consider steel stringers they will cost you about $25 per rise which is comparable to 250 x 50 f17 about $35 per metre. If you give your local steel fabricator accurate measurments ie total rise from slab to top of deck and explain that you want to bolt them to an existing slab etc. They should be able to make them up in a day or two.

stairs are a fairly challenging project, and potentionally dangerous, just think about how much force you put on the stairs when you run down them, then think about them giving way under that force, then think about the pain, then think about the litigation if it happens to someone else (just a couple of happy thoughts.

[capedcrusader]

Use galvanised or duragal angles to attach tread to stringers, preferably with roofing type screws.


Probably a dead thread but I d just like to add that Ive had the hex heads of 12 guage roofing screws shear off while fixing timber to timber through predrilled holes. I dont think theyre actually made of steel any more - some kind of cheap ***** alloy that barely copes but the 14 guage screws seem to be stronger. Maybe I just got a bad batch or something.
Regards

[ausdesign]

Hopefully you've built your stairs/steps by now 'antman' !
Regulation wise treads should be a minimum of 240mm deep with a max. of 350mm
Risers a minimum of 115mm with a maximum of 190mm in height.
As importantly each riser & tread should be equal.
There are more reg's in relation to handrails & 'gaps' between treads.