Home Forums Hunting & Shooting Hunter's Campfire Construction advise/options

Situation:

Our recently purchased rec cabin is "some assembly required". . It was started 20 years and two owners back. We finished filling in some insulation gaps and putting up the interior vapor barrier last weekend. And I thought I was slow! I guess there was more "recreating" than building? It came with 3 cases of beer......some of it frozen and leaking, some just bulged (probably still drinkable) , some seemingly factory standard. I haven't sampled any, but a guest did- says it's fine.

Building is 20 X 22, wood and 100 # propane tank heater for heat. Mostly wood.

First floor is unheated shop/storage/etc. with big bay doors. Area can get 8' of snow, so common design up there. Second floor is kitchen/living room/ maybe a bedroom later, third floor bedroom(s?) and storage. The floor between 1st and 2nd floor is 1/2 inch OSB over the stringers. Flexible between the 2' OC stringers, and no insulation. Drafty and cold down low. We are remodeling the layout inside, with a stairs to move - current one is a death trap! Hauled in the materials for the stairs last weekend- a mere $550. But we can't get there from here - need to take out a part of an existing wall, part of the floor on the third level, modify a support beam, and drywall that wall first. 8 sheets of sheetrock going in this weekend if the snow allows (breakup is underway) - built a hauler for it already.

The floor: sometime later this summer, hopefully before freeze-up.

1. I can patch in some 1x4 or 2X4 underneath the OSB seams to level and stiffen the flexing OSB seams between the stringers, insulate underneath with batt or foam board, and call it good. Getting the underneath insulation to stay in place would require much fitting and securing. Maybe add/ or instead some 1/2" finish grade plywood on top, running 90 degrees to OSB, putting long seams lengthwise over stringers. Advantage would be I can put in a higher R-value than #2.

2. I'm also thinking maybe 1" foam board OVER the OSB, with or without the underneath seam fittings, and 1/2 plywood over that. Either screwed directly into the stringers through the foam, or using 2x2 between the foam board pieces. Either would be less labor intensive than insulating underneath, and I think provide better gap-insulating. If more insulation is wanted later, that can then go in underneath, but I really don't think that will be necessary for our use, as based on the several 4-day weekends we've used it as is.

Spraying in foam underneath is not an option IMO - expensive and the cabin is over a mile off-road, accessible by ATV and snow machine trail, though at times by pickup.

My wife is re-arranging the whole layout, moving the kitchen to the diagonal corner, and some other stuff, but that's not a big deal to move a gas line, etc. No running water or drainage. At least not for years, probably. The wood stove stays in place to be built around. The wall mounted propane heater is probably going to stay in place also, but isn't going to interfere with any floor construction as is.

Thoughts? Any other floor options I am missing?

Use the Seafoam spray in expander insulating formula.
😁👍👍👍🤔🤔🤔😁😁😁

Irrespective of the question, Seafoam is always the answer

don't know that i would put 1" foam on the floor. i think i would sister in joist supports where needed and then go over the whole top with at least one layer of 3/4" plywood and tape the seams. t&g may be a beeotch in that scenario. i would do all the insulating from below.

and yes, maximize use of seafoam in all instances. gas tanks, crankcases, coffee pots, salad dressing and enemas. you can never have enough seafoam.

How much of a PITA to add some more floor joists? Are the existing ones on joist hangers? I would want to beef that up before I added anymore weight, though hard for me to tell as 1/2 OSB on 2' OC kinda sucks!

Sounds like you have joists that are too small. You have choices, add more, replace with bigger, or add a support beam across the middle. You could put down foam panels on the floor using firing strips and deck over the top. Spilt 2x4 would work for firing.

Assuming the floor joists are reasonable enough to support the additional weight... I would add wood glue to the existing OSB floor then lay down another sheet of OSB or plywood.

If you pre drill the new plywood the screws will pass through and draw the underneath sheet to the new sheet.

Stagger your seams of course. For good measure I'd go ahead and blast a few thousand narrow crown staples also.

As for the insulation, I would do from underneath... I know you said it was a PITA, but I still would.

Good luck.

I’d stick to the bathroom remodel at home! 🤣

Appears that joists are too small for the span; design and workmanship substandard.

What size are your joists? And what is the span? Just from your post, I am thinking you will want to add joists between existing joists, for a 12” center layout. This may not be necessary if the joists are sized properly for the span and load. Can you post some pics of the framing from the lower level?

Insulation, I would install fiberglass batt between framing members, and drywall and fire tape the lower level ceiling to both retain the insulation and create a fire break, as well as some air sealing benefit. Then sandwich 1” or more if possible foam board (Owens Corning Foamular 250 or equivalent) between the existing subfloor and a 3/4” overlay. All this is merely supposition based on your post, hard to be sure without actually looking at it.

LAS, where’s the cabin at?

Happy Valley maybe? Just a guess.

Any photos of the floor framing?

From the sound of it you have joists spanning 20’ without a mid-span beam. Easiest to just add a beam or framed wall mid span below the existing joists and would stiffen the floor right up. It will make modifying your stair framing easier in the long run too. I’d also add a second layer of 1/2” OSB glued and screwed to the existing. Insulating with batt insulation from below is probably the best option and I agree with drywalling and fire taping the bottom of the floor joists for a fire /draft break.

KINDA sucks? At the very minimum, I'd put down another layer of 1/2" OSB or plywood. As is, anything heavy that's set on it will sag. If you happen to get 2 or 3 people in a row between joists, it could get risky.

1/2 “ anything is not meant for floors ....well maybe steel plate .

Glue and nail 1 x 4 battens across the OSB and the floor joists at 12 inch centers then add another layer of whatever flooring you like over the top

This thread is useless with out pictures...wtf is wrong with you?

This.

A lot of work to make a place to have fun.

My wife, and I have done lot of that.

As said, picture always help.

Good luck with it!

WTF are you smoking ? And where did you get it?!

I'd look at this too. With 2' centered and 5/8" sheeting I wouldn't trust any run more than about 8' without a cross beem or wall. If you can add another joist between each of the others and go 1' centers and cover with 3"4" t&g you should be good for at least a 20' span with the proper joists and hangers.

I usually do 16" centers and 3/4" t&g and if the span is over about 18' I'll double the joists putting 2 directly together but keep 16" centers. I don't like bouncing floors.

Bb