Kiln Build

[DWyatt]

I am finally moving along with a kiln build at my new house. Dad's kiln box is getting tired and needs to be replaced. As a part of the build, I am also pouring a 4' x 44' concrete pad for air drying. I will preface this build with the fact that I understand that some of the things I am doing are overkill. The big cost is actually building this thing, the overkill is a small additional cost to ensure I don't have problems in the future. 

The kiln will be 10' x 16' outside dimensions with a 14' split door to be able to side load. Simple shed roof and ultra insulated to try to make this as energy efficient as possible. I am not doing a slab, I will put 2 layers of 2" insulation, then 2 layers of 3/4" plywood, glued and screwed together. 

Last night we got the air dry slab formed up and rebar installed. Again, the #4 on 12" centers is overkill, but I'm only doing this once. Digging footers on Thursday after work for the kiln and hopefully pouring everything next week.



 

[scsmith42]

What type of kiln are you building?  Solar, DH or conventional? (vacuum would not require a poured pad).

[K-Guy]

For either DH or Conventional kilns the pad for the chamber cannot extend past the chamber walls because the concrete will work as a heat sink and you won't be able to reach the higher temperatures.

[DWyatt]

I should have included that in my first post. We currently have a Nyle L53 that sits in a homemade garage door panel kiln unit. I will be moving that to service this new kiln.

The long concrete pad in the picture will be only for air drying, having a flat space to put my pallets of air drying wood. The kiln itself will be 10x16 exterior dimensions. I will pour a footer then lay a block stem wall. I will then frame up walls just like a house and insulate cavities with rock wool then continuous interior polyiso that will overlay the block and connect to the floor polyiso. The floor will be filled with compacted screenings. then I will place two layers of 2" polyiso inside the block, connected to the wall polyiso. Then two layers of 3/4" plywood.

Here's my working sketch. I call it a working sketch because it's mostly completed, enough to get quantities, then I'll just build the thing and never finish the drawing.

[doc henderson]

you are sparing nothing.  I have studied but never built a kiln so take this for what it is worth.  I worry over time you may get settling and have not a flat surface.  would a concrete floor slab be more stable and last longer?  Well-sealed and maybe even protected by a sacrificial replaceable plywood cover?  with insulation and a thermal break at the outside wall of course.

[DWyatt]

Doc, I would normally worry about that, but my place is a bit unique. I am about 12" to solid limestone bedrock on my property. I don't think that there will be much settlement. 

[DWyatt]

Footers are dug! The pictures are before we were done, it got too dark for pictures. Rock depth ranged from 36" to 10". We went ahead and dug out the center too since it is such a small area and it was all falling in anyways. 

You can see the area where the rock was 36" deep. It was about a 3' wide area.


 


This whole side was the shallowest, about 10"-12" to rock. 


 

[K-Guy]

The maximum chamber size for a L53 is 8 x 13, you will have trouble heating it and you are reducing airflow by going 10' deep.

[DWyatt]

I do appreciate the heads up on that. Inside dimensions will actually be 8'-5" x 14'-5", so not terribly oversized . I already plan to install 4 additional  auxiliary fans, which our current kiln chamber has, and from what I've read is necessary for uniform drying. As to the heating aspect, I will just have to wait and see. If I have issues, I will add auxiliary heat as well.

[DWyatt]

Since the rock is so irregular around here, I fill footers to somewhat level using 411 stone. 4" lifts, water then compact. Rinse and repeat. Footer is just about ready to pour. Got the inside formed and electric ran over the weekend also.



 



 

[DWyatt]

Concrete is poured! Stripped forms last night and this morning and started filling the middle up with stone. I'll take stone to the top of footer then the guy I'm having lay block can get started. The footer is way thick, but if I didn't do that, I would have had to add an extra course of block, plus I wouldn't have hit minimum load size which would have cost extra.

Only a few dog prints  :D



 



 

[DWyatt]

Footer is backfilled and ready for block. Teaching the kiddos how to run the compactor and had our 10 yo help with getting things laid out and chalk lines snapped 



 



 

[mudfarmer]

Very nice, do you have the air drying sidewalk filled up yet?  ;D we have been working on more/ better pallet bunks but should have been smart like you and just poured a slab!

[DWyatt]

Finally got my block mason here today and he got all of the block laid. You all get to view it with a flashlight just like I did after working a 14 hour day today  : 

Time to backfill this weekend



 

[Tom K]

Good to see some progress. I'm following along a few miles East of you with a vested interest. I need to do something come spring, still debating between a solar kiln or a DH kiln with a L53. Looking forward to see how you like this when your done.

[DWyatt]

Tom, I hope you don't get bored following along at my speed. My day job business is absolutely slammed, and we've got 4 kids. That doesn't leave much time to work on my extracurricular projects. If everything goes well, I will have this done by the end of the year. 

[DWyatt]

Got the tractor to the house and moved my cut lumber to the air drying spot. Progress is progress  :D



 

[DWyatt]

As promised, the progress is slow. I am building all of the walls in the shop then I will set them with the tractor. Building 16' walls in the shop means that everything is a wreck and everything is shoved to the back. I have the two long walls built, just need to make the short ones this week then maybe I can set walls and trusses this weekend.



 

[DWyatt]

Another little update. I finished up building the last wall last night. Just have to put the sheathing on it tonight. Unfortunately, it looks like this weekend is going to be a washout. Hopefully there is a lull in the rain long enough to get these walls stood up. The last wall has my access man door so I don't have to open the big door to check on things. The bottom plate will get cut out once I set the wall on the foundation.



 

[DWyatt]

Walls are standing! Dad came over and helped yesterday with the tractor, it took about 2 hours. That 2 hours included 17 trips from the kiln to my shop to get that one last tool that I forgot  :D 

Got the second top plate up today between rain and started to get things prepped for trusses including cutting and marking all the purlins so setting trusses will be quick.



 

[DWyatt]

Trusses are set. I was able to get off work a couple hours early yesterday and Dad came to help. Took about 2 hours. Just have to get the overhangs/facia finished up then it's time for metal. Overhangs save buildings, 2' minimum.



 

[barbender]

I agree, I'm a big fan of wide overhangs too. Looking great! 

[Andries]

Good Excellent "cap and shoes"!
That one will stand the test of time.
You're in NWOhio - the walls are 2x6 so plenty of room for insulation there. What have you got planned for floor insulation?

[DWyatt]

@Andries the walls are actually 2x8 which will allow me to do an r30 Rockwood batt. Then I'll put 2 layers of polyiso then plywood. The polyiso will be my air barrier and all joints will be taped. The upcharge to go from 2x6 to 2x8 was insignificant so I decided the more insulated the better, especially when trying to dry during the winter.

The floor will be 2 ea 2" layers of polyiso with 2 layers of 3/4" plywood over top. I am avoiding a concrete slab with my design. 

[Andries]

Nice!
2x8 and the polyiso are a solid way to go.
As DocH said: you are sparing nothing. 👍