building kiln

[Porta mill]

     new this site . I  purchased a portable mill last year and  have  mainly  milled lunber for  small projects . I am in the process of   buying a new house  and  want to build  an adition to the house  .I wanted to use wood I milled for the project . I live in hortheast P A and  in the least two years have instuted an inspection program that  makes it almost impossibe for a home owner build  his own home or additions.  They want the  wood dried to a 9% and  graded  so I am attempting to first build akiln and then find someone  who can grade the lumber and stamp it . To the main question I am thinking of building a shed of finding a trailer body insulate it put a few heat exchangers  in and using  my out door wood boiler to heat the hot water exchangers, water temp of the boiler is  165 to 175 degrees .put in a few fans to circulate the air .will this work for drying pine, hemlock, spruce ect. and  once in a blue moon some hard woods ? Aproxematly how long will it take to to go from standingt trees to 9%moisture  in the kiln I am thinking of building.  any and all inforamtion will be  gladley appriciated. I am also tring to find someone who could grade  and stamp the lumber . I live in north east PA.


                                                                            Thank you

[WH_Conley]

Welcome to the forum. I can't answer your questions, somebody will be along that can. Until then go to the front page and do a search on different combinations of works regarding kilns. If you don't plan on using a dehumidifier then sounds like a "conventional kiln", that should get you several hours of research. "Trailer body" will get you several more threads, several of the members here have already done what you are describing.

[Brad_S.]

Welcome to the Forestry Forum, Porta Mill. 8)

As Bill mentioned, you're describibng a conventional type kiln much like the small Koetter Kiln I have. I described how it operates in this thread: Direct Venting Kiln
Also as Bill recommended, do a search for trailers. There are special issues that need to be addressed if you plan to insulate a trailer.
Pine takes less than two weeks in my kiln and that is on a fairly conservative schedule. Softwoods are rather forgiving so it could be done a little faster. I do wonder if the lumber rules you have contain a typo. Most construction lumber like that found at Home Depot is only KD down to 19% MC.

[Don_Lewis]

Are you sure it is 9% not 19% they want? Either way, you'll need a kiln though you can get to 19% air drying but not so well.

I think you may be able to find an isnpector at one of the mills in the area who can stamp the wood for you. There are a lot of mills in Pennsylvania. Nyle has about 150 different customers in Pennsylvania alone using DH kilns. And that is just one manufacturer.  Visiting other people in the business is usually not a problem in this industry. Everyone is pretty open and willing and happy to show you around. Get a customer list for your area from the various kiln companies, visit some of the operations. It is fun to do anyway and educational. A few days spent that way will be worth the time.

[Kelvin]

Here is some of my experience.  Construction wood is pretty wet, at 19% MC pine is about done when cut.  You will have to sticker the wood anyhow, so once its stickered you will be to about air dry in a few weeks of decent weather.  No need to build the kiln for construction wood in pine.  You may want it for other things, but from my experience pine dries like crazy.  However if its winter and frozen it may take awhile.  Low moisture and higher temps help.  Wood still dries in the winter, but depends where you are.  Here in michigan we have very humid winters even in the single digit days.  If you are in a real hurry to dry, simply envelope the stack in a plastic tarp and add heat, and maybe a dehumidifier and check with a moisture meter.  Kilns don't need to be complicated.  Any heated buillding is a kiln if the moisture is low.  Got a heated garage, or shop?  Sticker it there and set up fans.  Don't worry, its easy.

For the stamping, graders don't just stamp anything.  You need to know what you are doing while you are sawing.  The placement of different types of knots and the way they are oriented to the surface of the board all impact what a particular piece of lumber is good for.  For rafters and floor joists you will want good strong boards without defects.  All pine has knots, how those knots come out in your lumber makes a difference.  Whoever you get to do the grading and stamping will probably tell you what they want done, but i would assume you will have to sort for types of wood needed and the working loads expected.  How much wane, depth of checks, loose knots.  Have it all ready to sort, stamp and look at.  I haven't personally been through this operation, but i've used lots of lumber in constuction and even if its stamped you need to pay attention to the lumber depending on where you are using it.

[Porta mill]

            Thank you for all the info everyone. yes I miss typed it is 19%  not 9 % sorry . I know a grader will not just grade any thing . I have a few arboresta that  supply me with wood. They cut it down then call me then I go pick it up  it is A win win situation   so I cand be a little more pickey about how and where the knots are placed  if it is to knoty or looks not to be quality wood  I turn it into 4/4 or use it  fire wood in my out door wood stove   . I have a construction backround so I think in my opinion  The wood I mill might be as good or better than  what I see in HomeDopet  of Lows . but if I am able to find a greader to stamp the wood he will tell ma if I am correct.as most OF the wood I recieve of very green andI have been told to get the moisture % down  the required 19 % a good rule of thumb is a year for every inch of thickness true or not  I do not know .I was thinking of building a kilf to get the process of drying done a little quicker but in reading  in this forum I might do more harm than good  drying it to quickly amoung other things  . guess I need to find someone closer to me that has a kiln that I could look at and  and see if my theory's will work

[Kelvin]

Howdy,
Now it sounds like you are thinking about options, thats good.  "one year per inch" is not really that helpful, and it actually pertains to hardwood.  I'd say one week per inch for pine.  (well, not that fast, but fast enough certainly)  Dry times reflect 3 things in a kiln operation.  Wind velocity, humidity and temp.  You can control with any one of these 3 things, but wind velocity only helps down to about 20%mc, where you want to be anyhow.  So just supply a little heat, little wind (fans) and you have a kiln.  Probably if you stickered the pine outside with a good cover and set it so the prevailing winds blew through it, by the time you built your kiln the pine would be 19%mc.  Make sense? 
Good luck.
KP