STAIRS  everything is based on equal triangles rise and run and rake of each tread is the same triangle as... the stringer and the floor... and the floor opening and the stringer nosing usually 25 mil not included in the run when building stringerCONCRETE STAIRS
CLICK HERE FOR concrete stairs HOW TO PAGE Balustrades  1/2 newel used for wall finish on balcony or landing balcony also landing newel used to support handrail   Baluster or spindle -holds
up hand rail -mark
tread centerline over stringer also  Knee wall as below: often used for semi open with balustrade built on top  Landing newel newel post at bottom of landing Open finish stringer -open to recieve tread and riser Over the post pinned to top of post Post to post -hand rail form flat to flat Rake Handrail -height from top of nosing to top of rail -lay handrail flush on nosings and square up marks on newel post -measure and plumb rail cut -slant of hand rail follows nosing line Return nosing -turns corner and comes to back edge of tread Rosette the piece that the rail is fastened to at wall Shoe rail bottom rail that holds balusters when applying spindle screw through bottom of ploughed shoe to fasten spindle... then when all spindles are attached screw shoe to plate on top of knee wall and then cut and glue fillets between spindles all connectors are hidden  Skirt board Runs above stringer on wall blends with base board top and bottom Starting easing -first upease Starting newel First newell Tread molding back of tread at joint Volute -tight turn of rail ...handrail termination  Closed finished stringer -is
applied after the risers are installed but before the treads -lay
finished stringer material across the risers and plumb down the cut out
marks and the cut outs for the top and bottom floor moldings walls
both sides Combination stair -width
1650 -max.
inside radius 2776 --tread
angle 5 degrees -3
transition risers -rise
150-172 laminated
thin layers, housed or mitered --inside
radius 990 -tread
angle 12 degrees -rise
150-172 -900
wide Dancing risers -nosings
are not parallel Framing  fastening
to header -I use a 3'4 plywood cleat nailed to stringers and then placed and nailed to header -2x4 thrust block notched into stringers and nailed to floor 
Calculating rise,
run, rake, headroom , stairwell opening Roy’s
theorem every
triangle has a rise, a run, and a rake so: for every simlar triangle
unknown over known times known equals
unknown rise/run
= % or tan x any run = rise rise/rake=%
or sin x any rake = rise run/rake
=% or cos x any rake = run rake/rise=%or
cosecant x any rise = rake rake/run=%
or sec x any run = rake hint
: draw out and label every triangle hint:
the top number is a percentage the bottom number is the number 1
headroom code clearance
for head from outer edge of nosing -1950
private -2050
public Housed finished stringer -routed -allow
400 on stringer for end cuts -quality
stock: oak, walnut, mahogany, -stringers
25
by 235 supported -top
edge of stringer 50 above nosing line -layout rise, run, bridge and nosing
Housed stringer template
-
template stock 600 by 750 by 6 -transfer
key lines from stock to template -draw
lines for riser and treads -draw
allowance lines for wedges 1:16 -allowance
for router collar (collar size minus router size equals allowance
divide by 2 equal
allowance for all around cutout -straight
edges clamped as guides -use
12 mil router bit -sand
all edges smooth -attach a layout board to bottom edge L staircase two
straight flights -trimmer
joist -outside
headers -partial
trimmers -tail
joist -partial
headers and trimmers are doubled -outside
trimmers -top
of landing level with top of riser -width up to 900 (1100
public) Length of stairwell distance from floor to ceiling plus total thickness of floor divided by unit rise equals number of risers .. . times unit run equals length of stairwell opening... add 75mm
Material -stringer
#2 or better 235 by 38 unsupported or 235 by 25 supported .. crowns up Math stair construction are all similar triangles, when calculating runs of stairs or runs of stairwells remember everything is rise run and rake any measurement that does not contribute to the rise , run, or rake must be subtracted out or added back in. All expansions of similar triangles are based on factors from the individual stair (riser, tread) unit :run over rise equals run factor, rise over run equals rise factor, rake over rise equals rake factor. Note rise over run equals tan .. . rise over rake equals sin .. . .run over rake equals cos Mitered stringer  -outside
finished mitered stringer is mitered to accept the riser so no end
grain is visible -the
nosing is returned down the side of the tread and extends past the
tread the same distance on each end - the riser is ploughed to receive the rabbit of the tread Stairs -3
risers minimum in anything but a single dwelling -exit
doors must be at 90° to direction of travel -
fire escape stairs must have tactile warning strip -
38 mm nosing or 60
degree nosing (minimum
tread depth less
.15) leading edge must have a radius or bevel 8 to 13 -service
min. 125 rise no max and max. 355 run no min. and max. 355 tread no min. -private..
rise max 200 to min 125, run max 355 to min
210 ,tread max 355 to min 235 -public
rise max 200 to min 125, run max 355 to min
230 ,tread max 355 to min 250 -
width min. 900 public between wall faces or guards -
width 860 private -
all landings shall be as wide and long as the width of the stairs but need not exceed 1100 -
exception .. landing private 900 exterior stairs -landings
required at top and bottom of stairs and at door openings -exit
door shall not decrease openings by more than 100 in exit corridors and
50 in other exits
the
required exit width ..750 on exit stairs -
exit stair 150 re snow block -winders 30° three winders max 1 set winders per floor .. run 200 from narrow end must conform to code... run at narrow end 150...
-handrails
1 to stair width 1099, 2 over 1100, 3 over 2200 and 2 sides of curved
exit stairs -handrails
865 to 965 height from nosing, diameter 30 to 50 or 57 cross section.. 40 between wall, -one
rail must extend 300 past top and bottom of stair must not obstruct -hand
rails .9 kn .7 kn -
single dwellings interior
2 risers no rail exterior 3 risers no rail .. over 3 one rail -1.2
between attachments attached to blocking 2 screws 32 penetration -guards
1070 protect against fall of 600 exception: guards at 900 for balcony, porch ,
deck etc. single dwelling 1800
high -openings
curb 150 guard 1070 -
guard openings 100 or less industrial 200 - openings will not be climbable wooden stringers: -throat
90 -235
overall depth (2x10) -25
supported width -38
unsupported width -exterior
wood stairs preservative only touches ground -one
dwelling stringers 900 on centre if risers support front 1200 on center -more
than one dwelling stringers 600 on centre steps: -25
thickness until stringers are 760 on centre than 38 thickness -slip
resistant finish other than dwelling concrete: cantilevered
must be anchoured in 200 wall foundation meeting code for depth Building -draw
your stair out full size on the wall -the
total rise divided by the desired depth of each riser round off the
answer for the number of risers -total
rise divided by the number of risers
gives the unit rise per each
stair -desired
run divided by the number of risers minus one equals
the unit run of each tread -unit
rise times the number of risers gives you top of landing. Begin to draw -
measure and mark out a level landing
line -at
floor level measure out landing and unit run times the number of risers
make a mark -
snap a line from this mark to edge
of landing
this diagonal line is your temporary top of nosing line from bottom to top of the diagonal nosing line -
from these marks plumb down your riser and level
across your tread line -
you are now looking at your upper stringer line drawn on the wall - draw a 90 degree line from the top of the diagonal line down the depth of your stinger and snap this line, now plumb down the depth of your landing and you have a picture of your total stringer on the wall -
from the bottom of the stringer shorten it the depth of the tread stock
and lengthen it for any finished flooring  Stairs -run
of opening = the run factor x (the headroom + floor thickness) + 75
fudge factor 
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