Using sheet aluminum (1/16″ thick sheets) under electric inflow heat to reflect heat upwards?
rattlingbooks
| Posted in Energy Efficiency and Durability on
I am going to install a small amount of electric infloor heat under a floating cork floor.
I plan to lay 1/4 ” cork underlay on the subfloor first and then the electric heating mats designed for use under floating floor.
I worry that too much of the hear will go to heating the house structure below and slow the heating of the target room as well as “stealing” heat from it (the floor below is a different apartment with a separate electrical bill).
To improve the functioning of the infloor heat I am wondering if using sheet aluminum under the heated mat would reduce heat loss below the floor?
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Replies
Janet,
Q. "I am wondering if using sheet aluminum under the heated mat would reduce heat loss below the floor?"
A. No, it will not. Aluminum is a conductor. What you want is the opposite of a conductor -- namely, insulation.
Thank you for answering so quickly.
Yes, I have insulation below between the floor joists (roxul) and I am putting the cork on the plywood subfloor as well to help with sound and insulate another bit between the heat source and the structure but I was curious if the aluminum would somehow reflect any heat back? like when they put the foil on insulation?
For aluminum to have any positive thermal benefit here there has to be an air-gap between the aluminum and the heating elements.
The primary function of facers on batt insulation it as a vapor barrier, and has no thermal benefit unless it is facing an air gap.
Appreciate these responses. Sounds like I will just stick to using the cork underlay to make up my needed thickness (it is a renovation so the sandwich I am concerned with is a fixed depth adjacent to a Terrazzo floor). No benefit to adding aluminum to it.