What to do when there’s no foundation?
Daiva
| Posted in GBA Pro Help on
We did a major renovation over 10 years ago. As part of that reno we enclosed what used to be a porch. One forced hot water register was installed and the underside of the flooring was covered with insulation. The room is very cold. It is approximately 4 feet in the air supported on concrete filled tubes. Other than digging and pouring a foundation under this space is there anything else we can do.
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Replies
Closed cell spray foam
Daiva,
There are two potential issues here:
1. Designing a thermal envelope (floor, walls, and ceiling).
2. Designing a heating system.
It's possible to design a heating system to keep almost any room warm. If your room is cold, then the heating contractor did a bad job of designing and installing the heating system. One solution is simply to provide more heat to the room, or to change the controls for the heat so that the room has its own thermostat. With enough heat, you'll be toasty warm.
However, it may cost a lot to heat the room if it has a bad thermal envelope. If the floor is cold, there is a good chance that you have air leaks as well as insufficient insulation. For more information on solving a cold floor problem like yours (by improving the thermal envelope), see How to Insulate a Cold Floor.
Close it in with non load bearing pressure treated framed walls.
Having a insulated non heated crawl space as opposed to 4' of open air will drastically change
the temperature delta.