Insulate Ice Castle Floor

Slappy

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Considering adding rigid foam insulation board to the underside of the ice castle floor. Anyone have experience with this approach?

Intent is to reduce hole freezing/shrinking and make it more cozy in the house. I push auger cuttings into the cavities around the holes and use hole sleeves that fit well but still have holes ice over too often.

Steel frame is 4" deep so thinking I will go with 2.5" foam board cut to fit fairly tight in each frame cavity. Will use small amount of adhesive and affix with exterior grade screws with large washers. Possibly add canned spray foam around edges.

If you've gone this route or know someone that has I'm interested to hear if it was worth it. Thanks.
 


Bauer

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I did my old wood fish house this way. Cut the board to fit between the floor joists and used some 1x1 boards screwed into the trusses to hold the insulation up against the floor. It has held up well for the last 15 years.
 

RP14

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I also have an 8x12 box that I want to replace the floor as well as add insulation. Thankfully the floor 2x4 is in good shape but have soft spots where we walk in center mostly. Was my bosses old ice house which was his fathers too (over 40 YO house).
They added a second sheet right on top of the old floor which probably sped up the floor rotting, I had it for 6 or 7 years now. Going to rip out the old floor to the joists, maybe add center 2x4 where the walk way is to strengthen that section. Thinking of using 2" silverboard foamboard (white foam) between the joist and add 2x2 boards to hold the foam up and also spray foam the edges for more support. Will be using 3/4" AC2 treated plywood, hopefully the linoleum will stick and the plywood doesn't stink up the place (off-gas).
House only gets pulled to the lake and home (35 miles 1 way) once a year with occasional move around lake as needed.
Open to suggestions and ideas.
TIA
 

lunkerslayer

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Have you considered having someone foam the underside of your Ice Castle, granted the initial cost would be more but i know you can rent the equipment to do it yourself. I would think that would be better because you can get a better R rating with less material. Also if you wanted to you could foam an area just around the ice holes if that is what you are trying to keep holes from closing up. But i always thought that ice holes will eventually close up because ice continues to expand?
 

3Roosters

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When ice melts underneath, make sure you either move house or raise off the ice so water doesn't refreeze under your house. Ask me how I know. I had to help a friend chisel his house out after it had refrozen to the ice, foam didn't survive.
 


Fester

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Doesnt menards sell spray foam kits? I think thats the route i would go.
 

JMF

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The foam will help but even in mine with an insulated floor you will still have holes freezing up. Best option is to add a few fans to move air around. I have 2 12volt fans on the ceiling pushing air down plus a couple small rechargeable ones directly over the holes that were sometimes still freezing up. They are like 15 bucks a piece on amazon and last a long time.
 

1lessdog

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I always drill the holes with house in the air. Then set the house down and get a good seal. Then go out and bank snow all the way around. When you think your done. Give it some more. If you can feel a breeze it's not banked good enough. I have never had a hole freeze up. I run two fans in the ceiling and one pulling heat heat off the bottom Empire 20,000 BTU furnace.
 

ORCUS DEMENS

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RP I would be hesitant to use "White Polystyrene" foam board as it can absorb water. Use the High Density blue or pink boards that do not absorb water. We used to use white foam boards in npools over winter to deal with ice pressures and they would be saturated come spring.
 

RP14

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RP I would be hesitant to use "White Polystyrene" foam board as it can absorb water. Use the High Density blue or pink boards that do not absorb water. We used to use white foam boards in npools over winter to deal with ice pressures and they would be saturated come spring.
Thank you. I'm not familiar with the white board. I'll use the pink foam. Thought about reusing the foil bubble insulation but think that's what caused the moisture retention under the boards. It kept the house floor warm. Like to try to get another 10 years out if it. It's nothing fancy, just a warm shelter to enjoy fishing.
 


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