Heatizon offers this handy R-Values chart, to help design your radiant heating application to determine the amount of heat needed or required.  To learn more about R-Values, visit this page.

Material
R-Value Per Inch
Typical Thickness
Typical R-Value
Plywood
1.10
3/4″
0.825
OSB
1.40
3/4″
1.050
Softwood
1.10
3/4″
0.825
Sheet Vinyl
1.60
1/8″
0.200
Vinyl Composition Tile
1.60
1/8″
0.200
Linoleum
1.60
1/4″
0.400
Linoleum
1.60
1/8″
0.200
Dense Rubber Flooring
1.30
21/64″
0.250
Recycled Rubber Flooring
2.20
1/2″
1.100
Cork
3.00
1 1/2″
1.125
Cork/MDF/Laminate
2.35
1/2″
1.175
Brick
2.25
1 1/2″
3.375
Marble
0.80
1/2″
0.400
Ceramic Tile
1.00
1/4″
0.250
Thinset Mortar
0.40
1/8″
0.050
MDF/Plastic Laminate
1.00
1/2″
0.500
Laminate Floor Pad
1.92
5/32″
0.300
Engineered Wood
1.00
1/4″
0.250
Engineered Wood
1.00
3/8″
0.375
Engineered Wood
1.00
5/8″
0.625
Engineered Wood
1.00
3/4″
0.750
Engineered Wood Flooring Pad
1.60
1/8″
0.200
Engineered Bamboo
0.96
3/4″
0.720
Oak
0.85
3/4″
0.638
Ash
1.00
3/4″
0.750
Maple
1.00
3/4″
0.750
Pine
1.30
3/4″
0.975
Fir
1.20
3/4″
0.900
Carpet Pad/Slab Rubber 33lb
1.28
1/4″
0.320
Carpet Pad/Slab Rubber 33lb
1.28
3/8″
0.480
Carpet Pad/Slab Rubber 33lb
1.28
1/2″
0.640
Carpet Pad/Waffle Rubber 25lb
2.48
1/4″
0.620
Carpet Pad/Waffle Rubber 25lb
2.48
1/4″
1.240
Carpet Pad/Frothed Polyurethane 16lb
3.53
1/8″
0.53
Carpet Pad/Frothed Polyurethane 12lb
3.48
1/4″
0.87
Carpet Pad/Frothed Polyurethane 10lb
3.22
3/8″
1.20
Carpet Pad/Frothed Polyurethane 10lb
3.22
1/2″
1.61
Hair Jute
3.88
1/2″
1.940
Hair Jute
3.88
21/64″
1.250
Synthetic Fiber Pad 20 oz
1.8
15/64″
0.421
Synthetic Fiber Pad 27 oz
1.98
18/64″
0.545
Synthetic Fiber Pad 32 oz
2.1
19/64″
0.630
Synthetic Fiber Pad 40 oz
2.2
11/32″
0.770
Prime Urethane
4.30
21/64″
1.400
Prime Urethane
4.30
1/2″
2.150
Bonded Urethane
4.20
21/64″
1.350
Bonded Urethane
4.20
1/2″
2.100
Carpet
2.80
1/4″
0.700
Carpet
2.80
3/8″
1.050
Carpet
2.80
1/2″
1.400
Carpet
2.80
5/8″
1.750
Carpet
2.80
3/4″
2.100
Wool Carpet
4.20
3/8″
1.575
Wool Carpet
4.20
1/2″
2.100