Footings, Columns,Beams, and Floor slabs

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Re: Footings, Columns,Beams, and Floor slabs

Postby Roger Ramjet » Mon Aug 20, 2012 4:09 pm

sirineou,
Have you ever tried to walk down those stairs? I agree with Geordie, the builder will not understand.
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Re: Footings, Columns,Beams, and Floor slabs

Postby Mike Judd » Tue Aug 21, 2012 5:59 am

I have mentioned this in other posts ( BUILDING HINTS) But it so important to allow enough room for stairs, ideally between 6 to 8 inches max for the risers and 10inches for the treads. As already said the risers must be the same height in each flight as your feet programme them selves from the first one and it avoids tripping. The bigger the treads are the better when going down as your feet have to clear the edge of the step that you are coming off of before landing on the next one.Angling the risers out doesn't give you any more tread to step on going down (only going up) Going up it's not a problem because your feet can use all of the tread. I don't know what it is with Thai builders but the number of stairs that I have seen with risers at 12inches , it's like climbing a ladder.! Better to make the landings smaller.
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Re: Footings, Columns,Beams, and Floor slabs

Postby geordie » Tue Aug 21, 2012 11:39 am

I actually do wonder if the basic principles of the new era "concrete construction" were imported from elswhere but part of the copying failed because they decided on higher ceilings the same No of stairs were put in it really does seem strange i have only ever entered 3-4 timber stilt houses and the stairs were comfortable open tread wood my mate has a steel/wood staircase in his house pattaya its the same comfortable but the half dozen houses i have been in looked at all seem as Mike states ladders ? a couple of extra risers could have made the stairs so much better ?
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Re: Footings, Columns,Beams, and Floor slabs

Postby fredlk » Tue Aug 21, 2012 11:47 am

geordie wrote:a couple of extra risers could have made the stairs so much better ?

My builder wanted 9 stairs in the staff house and I told him 11. His 9 would have had risers of 24 centimetres and be uncomfortable to use. Now the risers are 20 centimetres and it's just right.
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Re: Footings, Columns,Beams, and Floor slabs

Postby MGV12 » Tue Aug 21, 2012 4:07 pm

geordie wrote:but the half dozen houses i have been in looked at all seem as Mike states ladders ? a couple of extra risers could have made the stairs so much better ?


I am sure that you have also been in many a Victorian terraced house geordie .... they didn't believe in 'wasting space', as every square foot was needed for living space when trying to make these 'workers cottages' seem less like a rabbit hutch. I have remodeled [so the Americans understand :roll: ] a number of them .. kids aren't trained to be careful these day and tend to get hurt when they fall down the 'mine shaft'. If the stairs are for access to a loft conversion then you'd really need to practise with a bit of base-jumping before descending them!

I used to go up my grandmother's stairs on all fours and come down bouncing on my butt.

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Re: Footings, Columns,Beams, and Floor slabs

Postby Roger Ramjet » Tue Aug 21, 2012 4:13 pm

MGV12,
MGV12 wrote:I used to go up my grandmother's stairs on all fours and come down bouncing on my butt.

When you're in a situation like that I would recommend using your mother's best silver tea service tray to sit on; the speed is awesome and trying to stop before hitting the bottom door is adrenaline pumping material.
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Re: Footings, Columns,Beams, and Floor slabs

Postby MGV12 » Tue Aug 21, 2012 4:46 pm

Roger Ramjet wrote: I would recommend using your mother's best silver tea service tray to sit on; the speed is awesome and trying to stop before hitting the bottom door is adrenaline pumping material.


"using your mother's best silver tea service tray" ... hit the nail on the head.

In mitigation ... taking the seat out of my pants would be much more of a sin than taking the shine off her EPNS tray!.

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Re: Footings, Columns,Beams, and Floor slabs

Postby sirineou » Tue Aug 21, 2012 5:53 pm

I am sure they will do what ever works for them, and that adjustments will be made to comply with the realities of their build.
The code for stairs is,, and for good reason , no more than 8" riser (actually it is 7 3/4") and no less than 9" thread (step).
Usually what we do is to first calculate the stairs with optimal thread and rise dimensions, see how much higher or how much lower they fall from the desired height Rise), or length (run), divide that distance by the number of threads, and either add or subtract the product of the division to the steps. (I am sure you all know all this.) .
I am limited by the realities of the allocated space. I can not move the stairs forward, because they will stick past the downstairs wall by a couple o steps (I could live with that) and will reduce the head room under the upstairs hallway to less than 2 m ( i cant live with that). and I cant move them back because it will take away from the shower room ( shower 1m x 1m)
I cant make the upstairs Hall way any narrower (it is now 3 ft wide), and I cant move it, the center columns are in the way.
So, Unless I totally change the design of the floor plan, I am locked in to these dimensions.
What I have now is a 7" rise and 9.2 " thread, all with in unacceptable limits.
Changing the angle of the riser to achieve a .8" increase in the thread size and achieve a 10" thread,, is by an almost imperceptible angle. And should not have any adverse affect on walking down the stairs, all wooden staircases have a bull nose on the thread of about 1/2 inch , they have a 10" thread, and are fine to walk down.
For most of the House they can make adjustment as they build, but for the stairs they have to follow the dimensions or they will pay the price some where.
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Re: Footings, Columns,Beams, and Floor slabs

Postby MGV12 » Tue Aug 21, 2012 8:07 pm

sirineou wrote:For most of the House they can make adjustment as they build, but for the stairs they have to follow the dimensions or they will pay the price some where.


True story: I visited a house being built locally [Thai owner] at a very reasonable price for the size. When viewing it in the early stages I was appalled at the lean on many walls and, most notably, the stairs: Concrete had been poured and, I kid you not, the risers varied from 3" to 12" !!!!! Some months later I returned to view the finished article ... no leaning walls and stairs uniform within acceptable limits. I will never understand ... and can never accept .. why anyone would choose to adopt such practices.

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Re: Footings, Columns,Beams, and Floor slabs

Postby geordie » Tue Aug 21, 2012 10:28 pm

MGV12 wrote:
sirineou wrote:For most of the House they can make adjustment as they build, but for the stairs they have to follow the dimensions or they will pay the price some where.


True story: I visited a house being built locally [Thai owner] at a very reasonable price for the size. When viewing it in the early stages I was appalled at the lean on many walls and, most notably, the stairs: Concrete had been poured and, I kid you not, the risers varied from 3" to 12" !!!!! Some months later I returned to view the finished article ... no leaning walls and stairs uniform within acceptable limits. I will never understand ... and can never accept .. why anyone would choose to adopt such practices.


Incompetance and lack of supervision :|
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Re: Footings, Columns,Beams, and Floor slabs

Postby MGV12 » Wed Aug 22, 2012 6:25 am

geordie wrote:
Incompetance and lack of supervision :|


The Chinese-Thai owner lives on site; as he has a student apartment building next door. He was not at all concerned about the way they were working .. "as long as it's right in the end ... no problem". Hence the practise or using unsupervised and unskilled workers to do the basics will continue.

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Re: Footings, Columns,Beams, and Floor slabs

Postby BKKBILL » Wed Aug 22, 2012 8:56 am

sirineou,,

Got thinking about your stairs again.

Building them with a smaller tread, steeper rise may be within code but that doesn’t make them comfortable in use.

I understand the constraints of your design and a possible solution could be to bump out the outer wall.

This would allow

a smaller rise
larger tread
less room taken up in the hall
a larger bathroom with more head room under the landing.

You could go out as far as the roof drip line without altering it or costing a great deal more.
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Re: Footings, Columns,Beams, and Floor slabs

Postby geordie » Wed Aug 22, 2012 9:40 am

BKKBILL wrote:sirineou,,

Got thinking about your stairs again.

Building them with a smaller tread, steeper rise may be within code but that doesn’t make them comfortable in use.

I understand the constraints of your design and a possible solution could be to bump out the outer wall.

This would allow

a smaller rise
larger tread
less room taken up in the hall
a larger bathroom with more head room under the landing.



You could go out as far as the roof drip line without altering it or costing a great deal more.


a couple of extra colums a couple of extra footings but good thought makes the bathroom a better prospect
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Re: Footings, Columns,Beams, and Floor slabs

Postby Mike Judd » Wed Aug 22, 2012 2:44 pm

What you have now with a 7 inch riser and a 9.2 inch tread seems a reasonable compromise as space is the criteria. It is a common problem to not leave enough room for the stairs to fit into with out having high risers. It's so easy for the Thai builder to make the steps higher to get from A to B even if there is room for more steps(Less work) More thought in the design is the obvious answer, but unless you have been through all this before, it's usually too late when you get to that stage.
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Re: Footings, Columns,Beams, and Floor slabs

Postby splitlid » Wed Aug 22, 2012 3:08 pm

or you could just add a winder.
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