Recent content by Alan Waters

http://www.engineeringtoolbox.com/thermal-conductivity-d_429.html Granite does better than most as a thermal conductor. A lot better than concrete as you can see in the chart.

How do you zone without a manifold? The granite is part of the total heat holding mass. It is insulated from the the ground with two inches of polystyrene and 12 inches of sand.

Why?

To run eight loops of three hundred feet, what size feed line on the manifold wil be required?

I like the sound of the parallel serpentine. Both on 30 inch centers which would give me a tube every 15 inches. Is that to close using 3/4.

We rarely see single digits but 20's and 30's are common.

Is that for all diameters of Pex? Is there a formula for pump flow? Since the material comes in three hundred ft. rolls I plan to use a complete roll to make a loop.

Hello B.C. This is my first radiant heat project. I spent months thinking of a way to get more mass without using more expensive concrete. On my driveway I have what is called "crusher run" gravel. It is small gravel which has not been separated from the granite powder. A check with the quarry...

Hello. First post on the forum. Building a 40x80 with radiant. Had three courses of eight inch block laid. Layered about 12 inches of wet compacted sand. After the plumbing is done, two inches of polystyrene insulation will be laid on the plastic vapor barrier. There is a granite quarry nearby...