Maths..

[nate379]

Ok this is making my head hurt for some reason.

If I have a 20ft long wall and put a stud every 16", how many 2x8s would I need? 15 or 16?

 

[foss]

you would need 16

 

[BoydS]

yeap 16 studs are needed for a 20' run, but the corners are typically double studs so you can tie-in the adjacent wall at 90 degrees.

Why 2x8's ..? Is this a 2 story structure..?

 

[slghmmr88]

yeap 16 studs are needed for a 20' run, but the corners are typically double studs so you can tie-in the adjacent wall at 90 degrees.

Why 2x8's ..? Is this a 2 story structure..?

Lot's of insulation? Alaska?

 

[nate379]

For a floor, but was easier to explain as a wall... but 2x8 are standard for walls here. 2x6 is min code.

 

[tdkkart]

Do what I do when buying supplies, figure out what you need, 16. When you go to the lumber yard round up to at least 20 or 22. Guaranteed you're gonna need at least one more somewhere. I usually end up with about 1 left over when I'm done.

Related funny:
Last summer wife and I were finishing out my pole building, make at least 2 trips to the big box each week for supplies. Time came to buy the side wall insulation I did my figures, and of course for safety's sake added about 2 bags to the final figure.
Went to Menards, had a hell of a time with the whole deal.
First, the insulation was stacked to the ceiling in the store, couldn't find any help or a ladder, ended up climbing the insulation piles and knocking over the stack that I needed mine from. Then had to figure out how to get it all in the truck and tied down so we didn't have to make 2 trips. Finally got it all in, and only had to stop twice on the 20 miles return trip to re-secure the load.
Started putting up insulation the next day and quickly realized that I had purchased, loaded, and hauled exactly TWICE as much insulation as I needed. Had to load 1/2 of it back up and return it..........sigh!!!

 

[ddawg16]

Floor? Then you need to start at the corner of the wall.....you want the second joist to be at the edge so you can nail the corner of your drywall to it.

So, assuming 8" walls...8" top plate...I'm going to say 15 joists/studs.....plus the 2 outside....for a total of 17.

 

[nate379]

I'm going to get 20 probably since I need a few for blocking, but at $24 each I didn't want to just run down there and grab a trailer load.

 

[OccupantRJ]

Damn sure glad I don't live in Alaska if wood is that high.

 

[nate379]

My Dad said it was about the same price in Maine as well. This is PT wood, not reg 2xs

I need 10 sheets of plywood and that is $48/sheet.

 

[Torque1st]

You will need special fasteners for that PT wood. It is very corrosive.

From my experience the basic math on studs/joists is:
(length / spacing) rounded up + 1.
Then you can add in any specials needed like corners, bearing wall doubles, etc.

 

[Wingnut65]

And no matter how many you get, several will most likely be twisted, knotted or warped and can only be used for firestops or infill. Also consider doubling up the studs on the corners.

 

[little d]

+1 on what torque said, plus 2 for the end caps. also, just to make your head hurt a little more nate, depending on how wide your joist are going to run, ya might wanna add bridging to keep them from rolling on ya.

 

[nate379]

Yup, already planned on that. 16ft runs. Going to block on each end and in the center.

Wingnut65 last time I ordered wood and 1/2 the pile was like that. I set it aside and the lumber yard came and swapped it out. I wasn't paying for junk I couldn't use.

Torque1st.. galvanized nails, nothing special. Already have a few boxes.

 

[southpier]

for estimating, figure 1 stud per linear foot of wall. this gives you enough for corners & partition blocks. or do it the other ways and go back to the lumberyard and get more when you run short




btw: this is just arithmetic. mathematics comes with roof rafters

 

[nate379]

I am probably going to do a ridge beam setup for the roof. I thought about doing trusses, but it seems like it'd be more work for me to build them and then put them up.

 

[Indy_500]

My Dad said it was about the same price in Maine as well. This is PT wood, not reg 2xs

I need 10 sheets of plywood and that is $48/sheet.

HOLY BALLS! $48 per sheet! i would never build anything myself if i lived up there!

 

[nate379]

PT plywood, but the reg stuff is $41/sheet.

Cost of living is high, but so is the $$$ coming in so it equals out for the most part I guess. It's a small price to pay to live in the best state in the US.

 

[6768rogues]

A rough rule of thumb is one stud for every foot of wall length. Then there are generally enough to frame corners and an occasional opening.

 

[nate379]

I went back and bought 7 more boards, decided to frame it 12" OC. I am going to put an 8x7ft door, so if I want to put a car in there I will be able to.

My math works it out to 25 boards to do the framing and then I have 3 to use for the blocking.