[Robert-ON]

When we bought the house, my wife complained the stair rise is too high. Which I do agree. It is currently 8". And with the run being 7-7/8" (9" tread depth minus the 1-1/8" overhang), the slope is 45.91°. Every time I bring a big box or a basket of laundry downstair I'm worried of falling down. Going up is not as bad because it is an open stair.

As I'm finishing the basement, I wanted to rebuild the staircase, enclose it and add under stair storage.

The problem I'm running into this morning, is that even going by Ontario code limits, that floor opening is insufficient.

The floor opening is 230cm and floor thickness measured from top of finished floor to bottom of joist is 11" (28cm).

The headroom is required to be at least 195cm and is currently 196.5cm so I don't have a lot of leeway compared to the current bad stair slope.

Basement height is 235cm, with the upper floor thickness of 28cm, that makes a total rise of 263cm. The basement floor is not finished, we'll be going with laminate/vinyl planks.

With the floor opening serving as walls for living room, dining room and kitchen, I'm really stumped as for what I can do about it. Can I even reduce the joist ? It is 9", if it could be replaced with something else perhaps a metal beam I could gain a bit of height restriction. The problem is that it probably support the wall above it.

I calculated from omnicalculator.com, that using the code limits, I only have 185cm of headroom at the restriction point, which is 4" short, not including the drywall that need to be placed. So reducing from 9" joist to 5" beam... even if that is possible, would be quite the job, definitely not DIY and will cost how much ?

And keeping the stair as is, is not a solution as I need to add insulation to that cement wall as I'm finishing the basement so I need to rebuild narrower stairs. Can anything be done ?

I'm already forgetting about having comfortable staircase and concentrating on meeting code limits. We would have preferred a 10" or 11" tread depth.

 

[Nealtw]

Can you go thru and change all the numbers to inches.

 

[Robert-ON]

Can you go thru and change all the numbers to inches.

Sorry I'm too late to edit. But here is the dimensions in inches.

Current rise : 8" [code requires between 4-7/8" and 7-7/8"]
Current run : 7-7/8" [code requires between 8-1/4" and 14"]

Floor opening : 90-1/2"
Floor thickness : 11"
Ceiling height : 92-1/2"
Total rise : 103-1/2"

Headroom height at the point of restriction (ie. near bottom of stair) is currently 77-1/4". [Code requires 6'5" (77") of headroom]

 

[Nealtw]

Sorry I'm too late to edit. But here is the dimensions in inches.

Current rise : 8" [code requires between 4-7/8" and 7-7/8"]
Current run : 7-7/8" [code requires between 8-1/4" and 14"]

Floor opening : 90-1/2"
Floor thickness : 11"
Ceiling height : 92-1/2"
Total rise : 103-1/2"

Headroom height at the point of restriction (ie. near bottom of stair) is currently 77-1/4". [Code requires 6'5" (77") of headroom]

Our code calls for 80"

 

[Robert-ON]

Our code calls for 80"

I doubled checked and 1950mm (our code uses mm) is more precisely 76.77"

reference: http://ottawavalleyhandrailing.ca/resources-ideas/stair-measurements/

 

[Nealtw]

I doubled checked and 1950mm (our code uses mm) is more precisely 76.77"

reference: http://ottawavalleyhandrailing.ca/resources-ideas/stair-measurements/

I might cheat the riser and go with 7 15/16" and 10? runs


You can cut into the wall upstairs and support that with a header a little above the floor.

move the header in the floor back as much as you need

You can support the end of the floor above with an angle iron hung from the wall up stairs,

 

[Nealtw]

I doubled checked and 1950mm (our code uses mm) is more precisely 76.77"

reference: http://ottawavalleyhandrailing.ca/resources-ideas/stair-measurements/

If you measure out on the floor 130" and 140" and pull a string from the floor upstairs then you can measure from the string up on the floor and on the back of the wall to see what would need to be removed.

 

[Nealtw]

Double check my math that might be 140" and 150"
The stairs would end at 130 or 140 but you have to add 10 inches to get the slope to the floor.

 

[Robert-ON]

but you have to add 10 inches to get the slope to the floor.

ok, now i understand that 10". I'll double check the numbers and measure it tomorrow.

 

[Koa]

Would alternating treads pass code there. You can search the term and there are lots of different images. Here’s an example.

https://www.thisoldhouse.com/stairs/21015435/alternate-stepping

 

[Robert-ON]

Double check my math that might be 140" and 150"
The stairs would end at 130 or 140 but you have to add 10 inches to get the slope to the floor.

all right I plugged the numbers in omnicalculator, so 7-15/16" rise and 10" runs. 14 steps (but bottom step is 5/16" high). Total run is 130", pull the string at 140". I measure with the tape and to have my headroom, I need to cut 21" up and push back 28". The 21" up is problematic as it means part of the wall will disappear.

I then tried with 7.40157" (188mm) rise (to get 14 equal steps) and 9" runs. I get a total run of 117" (where the stairs end), pulling the string from 126". I measured that for my headroom I would need to cut 14" up (floor height is 11", so 3" up the wall on the staircase side of the wall, then angled downward, so on the dinning room side of the wall, the hole if any can be covered, as you illustrated) and I need to push back the header by about 16".

Finally, I also calculated from the other mathematical end. If I want a point - the base of the wall, dinning room side - to be a headroom up from the slope. Tan of 76.77" high and 94.5" long (opening + 4"), I get an angle of 39.3287. Which, when applied to the total rise of 103.5" places the string 126-3/8" away. Which is pretty much what I had in the 9" case (pull the string from 126") so I guess it was errors from pulling the string / measuring headroom.

Now I'll need to hire someone to that job with removing part of the header (the width of the final staircase) and supporting the floor to the upstair wall with an angle iron.

 

[Robert-ON]

Would alternating treads pass code there. You can search the term and there are lots of different images. Here’s an example.

https://www.thisoldhouse.com/stairs/21015435/alternate-stepping

Interesting. I think I'll need to call the inspector and negotiate with him if alternating treads would be ok.


But for a basement access (with living room, bedroom, bathroom, office) I think there is more chances he'll agree either on having steep stair (8" rise) or on having less headroom near the bottom of the stair before agreeing on alternate stepping.

 

[Nealtw]

all right I plugged the numbers in omnicalculator, so 7-15/16" rise and 10" runs. 14 steps (but bottom step is 5/16" high). Total run is 130", pull the string at 140". I measure with the tape and to have my headroom, I need to cut 21" up and push back 28". The 21" up is problematic as it means part of the wall will disappear.

I then tried with 7.40157" (188mm) rise (to get 14 equal steps) and 9" runs. I get a total run of 117" (where the stairs end), pulling the string from 126". I measured that for my headroom I would need to cut 14" up (floor height is 11", so 3" up the wall on the staircase side of the wall, then angled downward, so on the dinning room side of the wall, the hole if any can be covered, as you illustrated) and I need to push back the header by about 16".

Finally, I also calculated from the other mathematical end. If I want a point - the base of the wall, dinning room side - to be a headroom up from the slope. Tan of 76.77" high and 94.5" long (opening + 4"), I get an angle of 39.3287. Which, when applied to the total rise of 103.5" places the string 126-3/8" away. Which is pretty much what I had in the 9" case (pull the string from 126") so I guess it was errors from pulling the string / measuring headroom.

Now I'll need to hire someone to that job with removing part of the header (the width of the final staircase) and supporting the floor to the upstair wall with an angle iron.

When we build stairs we build then to be covered with hard wood or carpet so we build to the subfloor instead of the finished floor.
But it sounds like you have a plan anyway.

 

[Robert-ON]

When we build stairs we build then to be covered with hard wood or carpet so we build to the subfloor instead of the finished floor.
But it sounds like you have a plan anyway.

Ah, so if I understand you reduced total rise to 103-3/16" instead of 103-1/2". But then, I think it is actually 13 steps of 10" run x 7.9375" high. (13 x 7.9375 = 103.1875). And as the top step is actually the floor above, the total run is only 12 x 10" = 120". Now once the basement floor and each steps are covered, each step will be 7.9375" high including the last step that goes to the finished floor on main level.

Placing the string at 130", is very close to my theoretical 126", I won't need to cut much more and will give 10" runs which are better than 9" but stretches the riser by a 1/16th over the limit. Even maintaining my plan, I need to adjust to take into consideration the finishing of the floor and stairs. My wife did want a strip of carpet (less than full-width).

 

[Nealtw]

Ah, so if I understand you reduced total rise to 103-3/16" instead of 103-1/2". But then, I think it is actually 13 steps of 10" run x 7.9375" high. (13 x 7.9375 = 103.1875). And as the top step is actually the floor above, the total run is only 12 x 10" = 120". Now once the basement floor and each steps are covered, each step will be 7.9375" high including the last step that goes to the finished floor on main level.

Placing the string at 130", is very close to my theoretical 126", I won't need to cut much more and will give 10" runs which are better than 9" but stretches the riser by a 1/16th over the limit. Even maintaining my plan, I need to adjust to take into consideration the finishing of the floor and stairs. My wife did want a strip of carpet (less than full-width).

You are allow to have a 1/4" mistake so you could steel another quarter inch from the top step

we have got away with 7 1/4 rise with the second top at 71/2 and the top at 7 3/4 and that is to the subfloor.
Then keep in mind it passes inspection before drywall and hard wood is installed.

Will you be doing this stuff your self?

 

[Robert-ON]

You are allow to have a 1/4" mistake so you could steel another quarter inch from the top step

we have got away with 7 1/4 rise with the second top at 71/2 and the top at 7 3/4 and that is to the subfloor.
Then keep in mind it passes inspection before drywall and hard wood is installed.

Will you be doing this stuff your self?

I'm hoping to do the stairs myself. I do need to read more books on the topic. I have the permit for finishing the whole basement. I already did a little portion of the framing and will be framing/insualting exterior walls. I need to confirm about fireblocking. I didn't know the stair inspection would be before drywall and covering.


For cutting the header and adding angle iron, well, all the ceiling stuff, I'll hire someone. There is also some wires that needs to be moved. There is plenty of loop for the fire alarm, but the 3 black tv-cables are running exact length.

 

[Nealtw]

The way we frame walls w e just star with a 2x8 tight to the sill plate above the concrete wall. That is our fire stop and the top plate of the wall. And if you level or plumb down from that at the corners, your rooms are as square as the upstairs

Usually we frame, then plumbing, Hvac and wiring is done. Then we fix the framing around that stuff and you get an inspection before you can put in insulation.

Our insulation is inspected before the drywall is put up.
For your stairs, I would start with the wall on both sides then the stairs and the the ceiling. Ceiling last just in case you have goofed in the math.

BTW when you build rough stairs to be covered later you don't add the nose unless you are doing carpet, and that helps your measurement.

 

[carpdad]

Late to reply. Post 1, second image, header by the smoke alarm. You can trim it, make it into a triple header and trim the joists as well and double them. I may even go to 4 layer header and triple joists just to make inspector shut up. He/she may laugh but over engineering helps with overcoming the codes. That may give you enough of a headroom without having to move all wires. If not, move the header back.

About supporting the wall above, depends on what kind of wall. It may be supporting itself or light wall that needs no support. All it may need are 2x4s on flat lining the underlayment from below.
But you need 36" landing below. Lengthening the stringers may cut into that room.

 

[Robert-ON]

Late to reply. Post 1, second image, header by the smoke alarm. You can trim it, make it into a triple header and trim the joists as well and double them. I may even go to 4 layer header and triple joists just to make inspector shut up. He/she may laugh but over engineering helps with overcoming the codes. That may give you enough of a headroom without having to move all wires. If not, move the header back.

About supporting the wall above, depends on what kind of wall. It may be supporting itself or light wall that needs no support. All it may need are 2x4s on flat lining the underlayment from below.
But you need 36" landing below. Lengthening the stringers may cut into that room.

You noticed that room. When measuring 140" I did see the landing clearance might bump into that room if I lengthen too much. I hope I can manage without doing so, but in worst case, it is not that problematic. Fortunately, there is nothing behind that section of the wall and it could be moved. It is a utility room to enclose the gas furnace, air exchanger, and water heater. I think they went for a diagonal wall as the simplest way to do it, but an L-shaped room would also work.

 

[carpdad]

Utility room needs a certain size. A work room when the appliances need replacing. Check for those rules, I think they are online. I think at least 30" front and little less on the sides. I thought that wall was the foundation. If drywall and finished, you're ahead since you don't have to add frames to finish. Take a plumb line from the upstairs landing header where the stairs attach. Then measure to a point that leaves you 36" landing, including how the bottom riser is to be finished. Then you have the well that you can play with. For bsmt laundry and such, 7.5" risers are most comfortable, although if must, that can be changed. You may consider, if a closet or such, a laundry shuut (name?) and even a dumb waiter.:smile: