Have a century farmhouse. There is a root cellar (dirt floor) in the basement. Remainder of basement is concrete floor, uninsulated block and stone foundation. Basement is used for spare bathroom and laundry line. Heated by oil furnace and wood stove, so basement itself stays fairly warm.

Above the root cellar is the master bedroom. Floor for MBR is hardwood. Floor is extremely cold. My question is - what steps should be taken to insulate the MBR floor (and warm the room)? Can't afford to take any drastic steps now - need inexpensive solution.

If I put fiberglass bats in between floor joists on celing of root cellar, what about the vapor barrier? Which side is considered unheated?

Thanks for your help.

 

Conditioned space means you want to heat this space and an Unconditioned space means you do not want to heat this space. The vapor barrier in cold climates always faces the Conditioned space. Since energy can neither be destroyed or created and it takes money to buy energy to heat an space, then a Conditioned space is defined as a space you are willing to spend money on to heat. I am assuming you do not want to heat this root cellar which makes it an unconditioned space. Then the vapor barrier must face the Master Bedroom floor.

Cover the dirt floor of the root cellar with a moisture barrier, like a sheet of plastic, to avoid evaporation. The moisture in the dirt floor extracts the heat from the house to cause evaporation. Which is probably one of the reasons why your bedroom floor is so cold. The moisture barrier on the floor will prohibit evaporation, just like a solar pool cover.

 

The root cellar is not heated directly, but is connected to the heated basement through an open doorway. The basement has several registers in the ductwork for wood stove and oil furnace. Root cellar is the coldest room, but it is receiving some heat.

Would that make it a conditioned space?

I understand about putting platic on floor.

Regarding vapor barrier - if root cellar is conditioned space and room above it is conditioned space, what type of insulation would be put between celing joists. Unfaced fiberglass bats?

Thanks!

 

Unfortunately if the root cellar is a conditioned space, Why is your master bedroom floor cold? If you consider the root cellar a conditioned space, then unfaced insulation would be appropriate.

 

A conditioned space is a space heated or cooled by design or by accident.

If you have heating/cooling equipment that warm or cool the space even if it is only by 'accident', the space is considered 'conditioned' and needs to be treated as such.

That said, as Resercon stated, you have a conditoned basement abutting a conditioned room above.

In such a case, no vapor barrier is required because there will be times vapor flow will be 'down' during the heating/cooling year and times it will be 'up'.

I agree with Resercon.

Added insulation is fine, but no vapor barrier is required or desireable at all in this instance.