# Forum Home Renovation Stairs, Steps and Ramps  Tread Rise OK? and 1:100 slope across steps

## greg9876

Hi Everyone 
I am building steps from a landing to my new deck. Six steps (7 rises) of 165 rise by 267 tread will fit the space nicely. My question is will this ratio walk nicely.  
My second question is, the steps are coming into the side of the deck and both the landing and the deck will have a 1:100 slope for drainage. Is it OK to slope the step treads (left to right) 1:100 as well. That way I can keep all of the tread rises exactly the same.

----------


## BikeBoy

A slop of 1:100 I dont think you would be able to see this difference visually with the eye.

----------


## greg9876

> A slop of 1:100 I dont think you would be able to see this difference visually with the eye.

  I agree, I only remembered the slope when I started measuring up the steps and noticed one side was 15mm different to the other. I was just wondering what normally happens when a set of steps meets a (gently) sloping surface.

----------


## easterndecks

Just run your steps with the slope, it'll be easy to notice a difference in levels if you run the stairs level and not sloping with the deck.

----------


## greg9876

> Just run your steps with the slope, it'll be easy to notice a difference in levels if you run the stairs level and not sloping with the deck.

  Thanks, I will do that.  
Any thoughts on the walkability of 165 rise / 267 tread ratio?

----------


## boo

Hi Greg,  
When you deviate from the nominal 175 / 275 then usually as one measurement increases the other decreases. However, 10mm lower and 7mm shorter means they'll be slightly better for kids and people with short legs... Probably it's ok but why don't you stage it up and try it out then tell us? 
*Edit* probably more important is the consistency - each rise and run should be identical. If you make one wonky (including the very bottom and top) you create a trip hazard.

----------


## greg9876

Thanks for the input that 175/275 was the nominal size, I hadn't managed to find out what the nominal size was. I have been measuring all of the steps that I have come across and they are all over the place, I agree that all the same is critical, found some that were not and it was very off putting. I also found various links to the BCA  eg Stair safety -rise and going this has a nice graph of minimum and maximum values, but it didn't give any hint as to what the "normal" or "recommended" amount was. I have found examples of real steps that fit in the BCA table yet they are not nice to walk on. 
As an aside I noticed that Scott's metal standard stringer uses a ratio of 175 / 250, that seems rather steep to me.

----------


## boo

I made my garden steps 150:300. That was 1 sleeper by 2 sleepers. That's great for a garden and they are great to sit on AND walk down. So if these are for a deck I would err on the side of lower rise and longer run...

----------


## stevoh741

> each rise and run should be identical. If you make one wonky (including the very bottom and top) you create a trip hazard.

  Is ok to have the bottom one different without creating a tripping hazzard. Any other step with a difference will trip you though.

----------


## greg9876

I will make then as even as I can, I presume it doesn't have to be perfect I am aiming for getting them all within 5mm of each other. Or should I try harder... 
Started the steel stringers today, should be able to test walk some temporary steps tomorrow. If it is no good it will come apart fairly easily.

----------


## boo

> Is ok to have the bottom one different without creating a tripping hazzard.

  I have to disagree with that - sounds like a great way to break someone's ankle, especially an elderly person.

----------


## stevoh741

> I have to disagree with that - sounds like a great way to break someone's ankle, especially an elderly person.

  That's nice, but you are also disagreeing with Timber QLD (Publication: "Timber Stairs, Balustrades and Hand Rails - class 1 buildings - construction" who also state it is fine to have a different riser from the rest but at the bottom step only. Also I build decks (and stairs) for a living and although you try not to sometimes it is unavoidable to have a different riser at the bottom step (only). I also have a different bottom riser on a stair at my house and my elderly parents walk it often and have never tripped - nor has anyone else for that matter (because it is not a tripping hazard). It's fine to disagree but do it from fact, not opinion.

----------


## greg9876

I finished welding up the steel stringers today, I sat some planks on them and I am happy to say that 165/267 steps seem to walk fine (well at least for six of them).

----------


## boo

> That's nice, but you are also disagreeing with Timber QLD ... it is not a tripping hazard). It's fine to disagree but do it from fact, not opinion.

  G'day Stevoh, 
Mate, you've thrown down the gauntlet! I love a good argument ... especially with a Queenslander  :Wink:  
Yep, I disagree based on facts. 
Ok, so you've interpreted this from a doco, but let's crank it up a bit. It goes against the BCA's "constant throughout" requirement for stairs, that's the overarching fact. Now if these stairs are not from a non-habitable room they must follow the same conditions as a habitable room room OR AS1657. 
So, there must be a provision in AS1657 - "Fixed platforms, walkways, stairways and ladders"...?  Nope:  "All risers and goings in the same flight of stairs shall be of uniform dimensions within a tolerance of +-5mm." I don't see any exceptions in there at all. 
So Timber QLD have put in an exception? There must be a good reason why they know better - can you extract more info and post it here? 
So, my brain dump: 
The QLD doco's reference may be a concession due to the inability to include the landing within the BCA's definition of "flight" simply because the first reference point of measuring "a continuous slope created by the nosing line of treads" (again, the BCA definition) is the bottom step. i.e. there's no "point" on the ground as a reference point. But that's just semantics. 
Except for that, I can only see that it must be an allowance due to the nature of uneven ground that may exist at the step base, which would make sense for decks leading to the yard. Regardless, in this case you would make it as close as is practical to the centre-line height, or add a landing at the proper height (which I've done myself because of larger than expected drop). 
However, I still say it is a hazard for the bottom step to be a different height, just as it is potentially dangerous to make the bottom step just above an intermediate landing a different height, right? Just because (by lack of definition or exception) it may occasionally happen doesn't mean that it isn't a hazard and just because you don't "build" the ground doesn't mean you aren't responsible for safe passage onto it. The basic reason why it's important is not just to satisfy the Performance Requirement P2.5.1 (b) (iii) of the BCA (i.e safe passage) but because with any flight of steps you "expect" them to be consistant all the way. When they aren't, there's an increased potential for mishap = hazard.  
Regardless of all of this, you agree that the same height is safest right? Obviously you're not suggesting people can build the bottom step a different height just for the hell of it, so is the "sometimes" just for uneven ground?  
Thanks mate.

----------


## stevoh741

Honestly champ I cant be assed arguing this. I build them and on the occasion there is a small difference it is not as tripping hazard. However it is fine (and I really don't care) that you think it is so, if you build any stairs in the future you just do what you think is right.

----------


## boo

> It's fine to disagree but do it from fact, not opinion.

   

> just do what you think is right.

  Ok, but just note that I disagreed with facts from within the BCA and AS1657, which is what you asked for.

----------


## Bloss

Greg - don't guess - use the great tools on Blocklayer's site: Stair Calculator - Layout Stair Stringer, Headroom Rise Run - Metric why be 'within 5mm' when you can be within 1mm or less? As to the 'facts' vs 'opinion'  >40 years of practical stair building makes me support 'stevoh741' on this one. Standards are to try to ensure a minimum quality and performance  - they are never 'best practice' - my work _always_ exceeds standards.

----------


## boo

Great, thx Bloss. 
I totally hear you, but I'm still well short of the facts and/or reasoning why the bottom step rise can be different. 
Stevoh made a statement, which goes against the facts that I know and subsequently checked and posted here, then wouldn't back up that position because he "can't be assed". Thanks Stevoh, that's really helpful. 
The bottom riser a different height is not a hazard? Any other riser a different height is - what's so special about the bottom one?
Is it ok to make a step like this:   
Without any further explanation, you guys are saying it's ok. Do I have to do a Pauline Hansen?

----------


## Bloss

Ok - I'll bite, but a single post only (I've never failed  single inspection in >40 years, reckon I just might be doing something right and I read all the required material too so I'll take my chances on my understanding and compliance). 
Your diagram is insulting and misrepresents what I said and what stevoh741 said - he can reply for himself, but sensibly probably won't. In any case neither of us suggested anything that would give rise for a reasonable person to draw your sketch and in any case we both made reference to dealing with exceptions - not even remotely could it be inferred it was usual practice. 
BCA is in fact silent on tolerances for risers & goings - the nominal +/-5mm is to account for variation in timber (or other materials). Prior to 2001 the BCA did have section on 'acceptable tolerance values for stair dimensions' and that had an ‘Explanatory Information’ which suggested a 5mm variation on treads and goings as well as a 15mm variation on the height of the first and top riser as 'acceptable'. It was particularly noted that the tolerances were not intended to provide a means to accommodate poor workmanship or construction, but rather to allow for changes due to natural movement of materials and for unspecified floor or ground finishes. 
Since then there is no ‘Acceptable Construction Manual’ for the design and construction of stairs in the BCA (i.e. Part 3.9 provides an ‘Acceptable Construction Practice’ option only) and no relevant Australian Standard so there is no longer a recommended acceptable tolerance for stairs. 
That does not mean that because there is silence the +/-5mm is the only measure that strictly applies to top and bottom stairs. For as long as I can recall - and in that pre-2001 BCA information note, and from various notes and advisories from the MBA and HIA amongst others (I am not in Qld, but the Qld govt probably did this too) the 'acceptable practice' allowed up to +/-15mm variation for the first step (ie: bottom of flight) or up to 15mm _lower_ than the top floor level _or 5mm_ more than the last variation in last riser height (Steveoh741 said that his Qld note allowed bottom step variation only which seems reasonable to me given any fall risk is at ground level). 
I emphasise - as the standards require the primary goal is to have even risers and going (with steel and concrete and nowadays most timber used for stairs +/-1mm is achievable IMO not +/-5mm), but the variation I refer to is to deal with structural variability issues, not poor workmanship or shoddy materials.

----------


## boo

Hi Bloss and Stevoh, 
I'm totally sorry, Bloss. Of course it isn't meant to be insulting - it's meant to be ridiculous, because: 
1) Nobody was qualifying why or by how much it was ok to have a different riser on the bottom step until your post Bloss, and 
2) No-one has still explained how it can't be a hazard just because it's the bottom step. 
I'm not misrepresenting what was said - here it is, right here:   

> Is ok to have the bottom one different without creating a tripping hazzard. Any other step with a difference will trip you though.

  That throw away line is misleading and wrong on its own - it is right for me to question it. Is the the bottom step magic? It won't trip you like the others would? Am I taking crazy pills?? 
I just didn't (and still don't) know how you can back that up and when I disagreed I got rudely dismissed by a possibly obsolete and non-authorative document that never applied to me, instead of validated by the current authorative one that applies to everyone. 
Stevoh, so there's a +-15mm allowance somewhere? Dude, why didn't you just say that?? Or quote it???
I can see how that is part of the answer even if it's only partly relevant. Let's just say that that is what you meant, even though that's not what you said. 
Nobody is questioning workmanship or experience here either (not sure why it went to that.) It seems we all agree making all the steps the same height is the right thing. 
In the meantime, Stevoh if you can be assed looking back over this thread you might see how very unfair your responses were.   
Sorry Greg for the splatter. Don't mind us - 99.9% of the time this is the *best* place for great info. I'm sure your steps will turn out great.

----------


## stevoh741

ok last one. The "I can't be assed" comment meant I can not be bothered wasting my time argueing something that I know to be fact supported by the BCA, my own work (I am a carpenter) and others that I work with in the industry for someone that seems bent on proving their point that it shouldn't be. I'll give you some practical experience here and my thoughts as to why it is ok however do note that I don't plan to post any further on this issue so I hope this post will put you at some sort of ease. If you still disagree you could try and build a couple of sets of stairs and try differing size risers in different parts of the stair (ie top, bottom, middle) and assess for yourself which ones will trip you and/or elderly people. 
1. ok, the different riser as described in my earlier post is on a 12 tread stair at my house (built by others before I purchased it). It is a steel stringer with timber treads and a uniform 175/250 riser/tread setup. However the landing at the bottom has a (decent) fall (concrete slab) resulting in the bottom step riser going from 180mm to 195mm height till the first tread. Despite being quite different from the others (and what would be unacceptable had I built it) it is a comfortable walk and despite it sounding like a tripping hazard it is not and nobody has ever tripped on it.
2. I figure the reason bottom riser different is not a trip hazard is that your body has no idea the exact height of the step as you approach it. Therefore when you raise your leg to the first step you lift your leg to a height that will clear the first tread before planting your foot on it. Then, when you lift your second leg the height of the step up seems to register in the brain and so your body automatically lifts your legs to clear subsequent steps. If however in that assention a step riser is different then your foot as your climbing the stairs will either strike the tread earlier or later than your brain is expecting thus often resulting in a trip.
3. I did a job for a guy a few yrs back that had built his own external staircase and the riser 3 from the top was different to all the rest. Every single time I walked that stair I tripped even after knowing it was there.
4. So I have had first hand experience at different riser heights at both the bottom and at mid stair and the bottom one will not trip you whereas any other riser out (+or- more than a couple of mm) most probably will.
5. As for workmanship a lot of external stairs are made with steel stringers so the height is often set at 175mm and occasionally depending on the landing the bottom step can/may vary sleightly - unlike the drawing you posted which clearly takes the piss.
6. If you still think bottom steps are a tripping hazard take a measureing tape around the neighbourhood and measure any set of external stairs you find and you may be pleasantly surprised to find that lots of them have a small varience at the bottom riser (especially steel stringer setups) and as you have never tripped then you just thought they must have all had uniform risers.
7. As a tradesman if I built a set of tripping stairs I would expect to be sued and at the very least be called back to fix and as of yet I have never been sued or called back for stairs and I have constructed a lot of stairs in my time. 
Good that you quiery it as that is how we learn things but until you have actually tried and tested your theorys don't start arguements for the sake of something you think should be right. Good luck with any future stair endeavours you may construct or be involved with.

----------


## shauck

Stevoh's explanation is exactly the same as the one we were given in trade school.

----------


## r3nov8or

Point 2 of Steveoh's stands out for me. It's all about the brain and our awareness that we are about enter of exit the stairs and something may be different.  
If we were unable to subconciously and conciously adjust to a change in such circumstances we would never be allowed to use a stationary escalator, for the owners' fears of a flood of law suits...

----------


## boo

Great Stevoh, I totally appreciate you taking the time explaining your position, better late than never.  
You are saying: there are situations outdoors when you may have a different height bottom step. 
I am saying: differences in height increases the risk of a fall, including the bottom step. 
These don't exclude each other. 
So, you're opinion is that the bottom riser is *less* of a hazard on the way up if it's different, because of your experience at your house compared to another mid-step that you fixed. *edit - Yes, that's a fair but limited reason for coming to that conclusion.  
Forgive me, but I have to say this: 
Geez, man!! That's *not* what you said in your first post. You said it wasn't a hazard at all and didn't qualify why. You discredited my position, even though I've also fixed non-compliant concrete stair risers and also installed a bottom landing because of an excessive drop. Even now you're saying that I haven't tried and tested my theories. Damn straight I have, because it directly relates to some work I've been doing and they aren't just based on a step at my house. So I totally blame you for dragging me into this…   
OK *now* I've got that out of my system, we still agree the same height throughout is best.  
I have lots of resources on cognitive function because I have several projects at the moment that overlap into these areas, one specifically dealing with reaction time based on pattern recognition (like stairs) and one specifically with the elderly using Wii (i.e. step function). I might be able to write it down at some point, but won't post it unless someone wants to discuss with respect why it's still increases the fall risk with variation at any rise and why some risers may have other factors that help counter-act that.

----------


## boo

You know what? Let's just start again. I don't want to be accused of flaming or trolling, so here's a better response.   

> That's nice, but you are also disagreeing with Timber QLD (Publication: "Timber Stairs, Balustrades and Hand Rails - class 1 buildings - construction" who also state it is fine to have a different riser from the rest but at the bottom step only. Also I build decks (and stairs) for a living and although you try not to sometimes it is unavoidable to have a different riser at the bottom step (only). I also have a different bottom riser on a stair at my house and my elderly parents walk it often and have never tripped - nor has anyone else for that matter (because it is not a tripping hazard). It's fine to disagree but do it from fact, not opinion.

  Thanks Stevoh, I'm sorry you think I don't have facts. Here's some simplified answers: 
If you are on your way UP the stairs: the bottom teaches you the wrong height of the NEXT step. The bigger the difference, the greater the risk of tripping or landing hard, potentially causing injury. 
If you are on your way DOWN the stairs: the more weight and reliance you are applying to the last step as the handrail is let go, so the greater the impact of misjudging the height and the greater the risk of injury. 
Being aware that you are starting or finishing a flight of stairs surely does help minimise the risk, but doesn't remove it. 
I hope this helps and can back this up further if needed.

----------


## ringtail

On the way up is no drama, its on the way down that catches  people out. It happens to me quite a lot where the bottom step is more than the rest ( rarely when its less) and I find it really easy to jar your back as you hit the ground with the leg much straighter. However I do tend to find that if I have walked up that particular staircase then coming down is no problem. Its more if I walk up the front stairs but out the back stairs in a new place and its the last step on the way out. Technically, all rises *must* be the same. If its uneven ground at the bottom then level it out, put a concrete pad down, whatever. The certifier is quite within their rights to knock em back ( hardly ever happens though and I see dodgy stairs every day on new houses - say no more)

----------


## shauck

I wonder. Seeing as we've all walked up and down stairs our whole lives, experiencing various last steps that are slightly different from the rest, don't you think we are all naturally cautious regarding any last step? If we can quickly learn the stride of a set of steps, don't we also learn this? I know i am careful on any stairs. I can really hurt if my lower back jars suddenly. It's very delicate. Not advocating different height in last step by the way, I'm all for perfect as possible. Just interesting convo.

----------


## Bloss

As 'ringtail' says it is when stepping down that people have trouble ('mostly' not 'only') and there are many good studies to support the rule about being evenly spaced. This is made worse for anyone with impaired depth perception especially (and tricky for those using bi-focals or tri-focals to correct vision!), but also for any other sight impairment too. The aged are particularly vulnerable to all fall & trip hazards. The issue arises for the general population too and some mental health conditions can cause processing errors (autism for example).  
As had been said this should be the exception as there are usually ways to achieve the correct rise - as ringtail also said one does see too many examples of bad design and/or construction.

----------


## ringtail

Most common problem from a construction point of view is the builder hardly ever takes into account the finished level of the ground. The stairs are built and then a concrete path is laid without taking the first rise ( or total rise) into account. More often then not the bottom tread and / or bottom of the stringers are embedded in concrete and apart from being illegal, the rot starts as soon as it rains and the termites now have wonderful access to the house.

----------


## greg9876

> Greg - don't guess - use the great tools on Blocklayer's site: Stair Calculator - Layout Stair Stringer, Headroom Rise Run - Metric why be 'within 5mm' when you can be within 1mm or less? As to the 'facts' vs 'opinion'  >40 years of practical stair building makes me support 'stevoh741' on this one. Standards are to try to ensure a minimum quality and performance  - they are never 'best practice' - my work _always_ exceeds standards.

  Hi Bloss, sorry for my tardy reply I have been away for a while. The reason that I wasn't going for 1mm or less is that my steel fabrication skills are not up to that standard. :Cry:   However reading the discussion in this thread has highlighted the importance of of getting the treads equal. My steps are going to be tiled and I am a much better tiler than steel fabricator, I expect to get them very close to equal at the tiling stage. Thanks for your input.

----------


## greg9876

Hi all, for those interested I have constructed the steps and I am happy to report that a 165mm rise with a 267 tread walk fine. Going up is very easy and comfortable. Some posters said that the treads could have been a bit longer. I agree with this if I walk down in the dark (I know steps in the dark is a bad idea) sometimes the back of my heal will just touch the vertical face of the previous step. This doesn't happen if I think about walking down the stairs, it only occurs if I take a very casual walk down, even then it is not close to a trip rather the back of the foot might touch the face of a previous step. Perhaps it might be an issue to someone with size 14 feet.  Interestingly I think the standard steel stringers that you can by in 175 rise 250 tread  would be rather worse. 
Also sloping the steps (left to right) 1 in 100 the same as the deck slope looks absolutely correct. In fact you cannot tell at all that the steps slope a bit, and of course the water will drain off. 
Thanks for all of the input, it was of assistance. Now to think about 40 sqm of tiling....

----------


## boo

:2thumbsup:

----------


## Bloss

Glad it worked out well - enjoy the tiling . . .  :Wink:

----------

