You don't want airflow. That is an old building myth. A nicely sealed building is sealed in terms of air and water vapor. Warm humid air from inside would condense in the insulation and on the interior of the walls if you didn't have that vapor barrier in place. Over time that would mold and rot the wood. Makes sense right? The barrier keeps the inside air on the inside of the house. the insulation prevents that condensing on the inside wall interior (next to the drywall and under the floor) by having the air gradient that is inherent to insulation... It all works. There is no way to seal a home so much that you would need to worry about oxygen without trying really hard. Those homes are passive certified and have to have active air intakes built in. yada yada yada.
@@TheMacroSlacker You want as MUCH air flow as possible. To keep moisture dry. Homes built decades ago following bad code are mold infested nightmares. New code demands spacing tween insulation and ext/int walls or they won’t pass code. Times have changed and hopefully less mold deaths will result.
I see soo many videos of builds that people close the bottom, top and bottom of the floor. I looked a lot, I’ve done lots of looking into this since I’m building a 12x16 shed that I’m building with a residential quality build in case I want to use that for a workshop down the road. Anyways, my floor, I’m using 3/4 plywood, then 2” foam board R 10 value, then 1 1/2 “ space “this space here separates my warm side away from the cold side. When warmth meets cold that’s your condensation”, then foam board 2” R 10 value and not closing the bottom so if there’s any! Moisture it doesn’t get trapped. There could be condensation at the bottom, I’m also building on piers so there’s plenty of air circulation. I’m adding 1/2” hardware cloth so critters don’t try getting in, specially mice. Mice are smart, so it’s worth a try, I’m stapling it under my joist. I just thought to comment in case it helps anyone, I learn a lot from comments too.
hey hows she holding up? planning on building a similar floor set up but i heard sandwiching insulation can lead to moisture. Im new to building so i dont know.
All has been good with the cabin. Nothing to report. This type of construction with the insulation sandwiched is how homes are built in my area. As long as the vapour barrier is on the warm side of the insulation any moisture that could accumulate on the outside of the vapour barrier can dry to the outside
Hey Sandy. Given that your floor is made with green lumber, is there any worry about losing insulating capacity as the lumber shrinks and opens gaps between the joists and insulation?
This was another great vid Sandy, nicely done on getting everything insulated and VB. Such great content! Andrew from NB :)
Glad you found this build and are enjoying it
Perhaps use the reflective bubble sheets instead of plastic...tape the seams and enjoy the radiant reflective warmth.
You struggling with the gloves was like watching myself finding a pair of gloves to go to work. Kind regards Christiaan
Thank you for taking water vapour pressure seriously when educating online!
Thanks for watching Amanda
There might be condensation on the plastic since it doesn’t breath, is there going to be air flow?
You don't want airflow. That is an old building myth. A nicely sealed building is sealed in terms of air and water vapor. Warm humid air from inside would condense in the insulation and on the interior of the walls if you didn't have that vapor barrier in place. Over time that would mold and rot the wood. Makes sense right? The barrier keeps the inside air on the inside of the house. the insulation prevents that condensing on the inside wall interior (next to the drywall and under the floor) by having the air gradient that is inherent to insulation... It all works. There is no way to seal a home so much that you would need to worry about oxygen without trying really hard. Those homes are passive certified and have to have active air intakes built in. yada yada yada.
@@TheMacroSlacker You want as MUCH air flow as possible. To keep moisture dry. Homes built decades ago following bad code are mold infested nightmares. New code demands spacing tween insulation and ext/int walls or they won’t pass code. Times have changed and hopefully less mold deaths will result.
Does the three-quarter inch plywood need to be tongue and groove?
Good job.
So do you think the particleboard left untreated, will collect condensation? Shouldn’t that particleboard be salt treated?
Still going strong 3+ years later
I see soo many videos of builds that people close the bottom, top and bottom of the floor. I looked a lot, I’ve done lots of looking into this since I’m building a 12x16 shed that I’m building with a residential quality build in case I want to use that for a workshop down the road.
Anyways, my floor, I’m using 3/4 plywood, then 2” foam board R 10 value, then 1 1/2 “ space “this space here separates my warm side away from the cold side. When warmth meets cold that’s your condensation”, then foam board 2” R 10 value and not closing the bottom so if there’s any! Moisture it doesn’t get trapped. There could be condensation at the bottom, I’m also building on piers so there’s plenty of air circulation. I’m adding 1/2” hardware cloth so critters don’t try getting in, specially mice. Mice are smart, so it’s worth a try, I’m stapling it under my joist.
I just thought to comment in case it helps anyone, I learn a lot from comments too.
Hi Sandy, seeing as you milled all your own wood, wondering why you didn't make the subfloor out of planks instead of plywood?
I thought I may end up leaving the floors as plywood without flooring overtop originally
hey hows she holding up? planning on building a similar floor set up but i heard sandwiching insulation can lead to moisture. Im new to building so i dont know.
All has been good with the cabin. Nothing to report. This type of construction with the insulation sandwiched is how homes are built in my area. As long as the vapour barrier is on the warm side of the insulation any moisture that could accumulate on the outside of the vapour barrier can dry to the outside
So how is the floor actually attached to your foundation?
Subfloor is screwed down to the floor joists. Posts are set on concrete blocks
@@sawingwithsandy Yes, but how is the whole subfloor structure attached to your logs/foundation?
Hey Sandy. Given that your floor is made with green lumber, is there any worry about losing insulating capacity as the lumber shrinks and opens gaps between the joists and insulation?
Great question Robbie. Since the insulation is pushed up snug against the floor joists and the wood won't shrink too too much I'm not too concerned.
Sandy, how did you fix the joists to the bearers or is it floating? Thanks
I nailed them to the beams underneath
That’s so much me with the gloves 😂
Dont use batt insulation in the floor like that. Once mice and rodents get it and they will..they will have a field day.
Dude had get off here the camera work made me dizzy tripod that camera
I hate mosquitoes.
I’m there with ya Dean!