Wood types for building

[puddle jumper]

I live in an area that has lots of ceder. Does ceder work well as house building wood. I am looking to redo my roof trusses next year and can get cedar dimensional wood for free or should I stick to pine/spruce.

 

[marlboro180]

Re: Wood types for biulding

Re: Wood types for biulding

Stick to SPF for any structural components.

 

[moonfish]

Re: Wood types for biulding

Re: Wood types for biulding

I think cedar would sag too much. Around my parts it's all fir.

 

[Bigprairie1]

Re: Wood types for biulding

Re: Wood types for biulding

Puddle Jumper, cedar is great for applications subject directly to a lot of moisture, like deck surfaces, trim, shakes, etc. However they have poor structural strength qualities in comparison to the spruce, pine and particularly fir products. You will pretty much never find them 'size for size' used in a structural application as per code.
If you want to save a few bucks, keep an eye for a 'tear down' of an older structure and older 2x4's for sale through a demo sale, etc.
I have found that the older 'demo' wood to usually be almost always tighter grain fir, and almost always, straighter and stronger than the newer stuff you would find at home depot. The only issue you have is to take a little time and de-nail them and often trim off the ends to get a nice, new surface.
That said, a lot of this older wood came from (unfortunately?) the old growth forest stuff when it was harvested in the 40's/50's/60's and it is beautiful wood in comparison. I don't think I've seen a nice straight, clear fir 2x4 in home depot in quite a while. Mostly 'joined' spruce...and a lot of that is like searching through a pile of curved water ski's.
Good luck
BP

 

[MrBigStuff]

Re: Wood types for biulding

Re: Wood types for biulding

Bigprairie, you reminded me of the time a guy came to install A/C in the house my Dad built back in the 50s. They built things to last back then. The exterior had tongue and groove subsiding. But I digress... All the joists were douglas fir. The guy doing the install was having a lot of trouble drilling holes in the joists. He kept saying how tough the wood was and that "they don't make 'em like this anymore". It was hard to pound nails through that stuff!

 

[itsaboattime]

Re: Wood types for biulding

Re: Wood types for biulding

A piece of lumber's strength comes from how tight the grain is. The hard woods, Oak, maple, poplar, have tight straight grain. Pine, fir and spruce woods have wider grain. Cedar has a wider grain than pine spruce and fir. The wider the grain, the weaker the lumber, the thicker the piece of lumber needs to be to be structural. Roof trusses made of cedar would be impractical because of the size of the lumber. You have to take into account the rise and run of the rafters(top member of a truss) and the thickness and weight of intended sheeting and the weight of the intended roofing material. Plus if you live in an area that has snow, the weight of the average yearly snow load. Plus what is the code for how many layers of shingles can a roof in your area have? Your new rafters have to be able to support that much weight without bowing or failing. My rough guestimate is that your cedar rafters would be close to 4 X 4's. Or dimentional 2 x 12's.

I am a carpenter by trade. Cedar is not used as structural wood for a reason.

 

[puddle jumper]

Re: Wood types for biulding

Re: Wood types for biulding

Thanks for every ones input. I figured that I would have to stick to conventional woods for the project.

On the flip side I can get 4x4s, 2x12s,4x12,12x12s,16x16s,ect up to 50 feet long. Not that I would get that long of wood but I could. Also I have seen lots of sheds built from it.

Bigprairie I have built lots of projects from recycled wood with out any problems just nothing available at the moment.

 

[itsaboattime]

Re: Wood types for biulding

Re: Wood types for biulding

WOW Puddle!!! That kinda lumber around here is ablut $10.00 and up per board foot!! You that stuff for Free?!?!?!

 

[puddle jumper]

Re: Wood types for biulding

Re: Wood types for biulding

WOW Puddle!!! That kinda lumber around here is ablut $10.00 and up per board foot!! You that stuff for Free?!?!?!

That,s what you can get when you live in a rain forest. The trees here are huge and plenty full. My friend has his own mill and sells the grade A/B wood to lumber stores but any wood that does not make grade gets burnt. Most of the junk wood has nothing wrong with it but does not look the best and he has an huge abundance of it. Plus I also do some mechanical repairs for him if he needs a hand.So he makes me anything I want.

I bet some of you would love to have a deal like that. It can make for some cheap building.

 

[rbh]

Re: Wood types for biulding

Re: Wood types for biulding

If you know any one that works for bc hydro and you have access to a mill the old poles they are getting rid of are not all western red cedar any more, lots of pine, try them.

 

[puddle jumper]

Re: Wood types for biulding

Re: Wood types for biulding

Not a bad idea on the old telephone poles rbh.

 

[moonfish]

Re: Wood types for biulding

Re: Wood types for biulding

A piece of lumber's strength comes from how tight the grain is. The hard woods, Oak, maple, poplar, have tight straight grain. Pine, fir and spruce woods have wider grain. Cedar has a wider grain than pine spruce and fir. The wider the grain, the weaker the lumber, the thicker the piece of lumber needs to be to be structural. Roof trusses made of cedar would be impractical because of the size of the lumber. You have to take into account the rise and run of the rafters(top member of a truss) and the thickness and weight of intended sheeting and the weight of the intended roofing material. Plus if you live in an area that has snow, the weight of the average yearly snow load. Plus what is the code for how many layers of shingles can a roof in your area have? Your new rafters have to be able to support that much weight without bowing or failing. My rough guestimate is that your cedar rafters would be close to 4 X 4's. Or dimentional 2 x 12's.

I am a carpenter by trade. Cedar is not used as structural wood for a reason.

Actually, wood gets it's relative strength from its density. Heavy wood is usually strong wood.

Puddle Jumper, I'm sure there is something you can use from your friend's saw mill but you never mentioned anything beyond cedar.

 

[itsaboattime]

Re: Wood types for biulding

Re: Wood types for biulding

ummmm moon........I believe that's what I said. "tight straight grain". Density cannot be measured by a piece of wood's weight. A wet, or "green" peice of pine can weigh as much as the same size piece of Oak. Is it just as strong?? Of course not. The grain of the lumber determines the strength.

A good rule of thumb we use when building is "the tighter the grain, the stronger the piece of lumber." I've seen 2x4's come to the job with literally no or almost no grain at all. You can break them over your knee. We don't use them.

Count the lines of grain in a piece of Oak, then count the lines of grain in a same sized piece of pine. The oak will have more and thus be stronger.

 

[puddle jumper]

Re: Wood types for biulding

Re: Wood types for biulding

Puddle Jumper, I'm sure there is something you can use from your friend's saw mill but you never mentioned anything beyond cedar.

He said he can also get Spruce. Just the Ceder is so plentiful and free.

 

[moonfish]

Re: Wood types for biulding

Re: Wood types for biulding

ummmm moon........I believe that's what I said. "tight straight grain". Density cannot be measured by a piece of wood's weight. A wet, or "green" peice of pine can weigh as much as the same size piece of Oak. Is it just as strong?? Of course not. The grain of the lumber determines the strength.

A good rule of thumb we use when building is "the tighter the grain, the stronger the piece of lumber." I've seen 2x4's come to the job with literally no or almost no grain at all. You can break them over your knee. We don't use them.

Count the lines of grain in a piece of Oak, then count the lines of grain in a same sized piece of pine. The oak will have more and thus be stronger.

You can lookup the specific gravity for different kinds of wood on the net. This is how the density is measured. There is a standard. You can find all kinds of specs for types of wood. Crush strength, janka hardness rating, modulous of elasticity, weight per cubic foot, both for dry and green wood, etc.

I can't count wood grains. I think you are using the wrong terminology. You can count growth rings on the end of a board sometimes but you can see the direction of the fibers i.e. the grain if you split the board and the little hairs are the actually the grain of the wood. All wood is going to have a grain to it. The grain might run perpendicular to your board and the board might be worthless but it still has fibers that orient in some direction at a given point.



http://www.hoganhardwoods.com/hogan/pages/technical/Technical_01/densitygravity.htm
Density (weight per unit volume) is probably the single most important indicator of strength in wood and may predict such characteristics as hardness, ease of machining and screw and nailing resistance.