Suffering Snot Balls: It Actually Worked!

Okay, so many of you I consider near-friends, but I admit I was EXTREMELY hesitant to tell you my radiant floor plans for fear that you would talk me out of it. Honestly I did not think it would work, and while doing research on it found out that an engineering firm considered it then backed out feeling in theory it would work, but in practice it would fail.

The problem I had is that my home has been built in stages over the last 20 years. Part of it was built before radiant heat was routinely done, and part of it was done afterwards. I LOVE RADIANT HEAT so I wanted to convert the kitchen and living room zone into radiant heat. I used 3/4 inch wide pine flooring laid on 1" sleepers Hilti-Gunned to the concrete. Then I laid down the pex tubing along them to heat the floor. (The concrete slab is thermally isolated from the ground via 2" Styrofoam insulation). But what to do with the space between the floor and the concrete slab and around the pex? I certainly did not want to mix by hand that much concrete over that much surface area so I decided to get creative.

Knowing on wooden ships that built fires by placing the logs on piles of sand laid over the deck, I mixed and poured concrete on the first two feet of space from the outside walls, but on the inside just poured in live sand and graded it off before laying down my pine flooring. After hooking up the radiant floor last week and letting things crank away there is no difference between my entirely concrete radiant slab and my concrete/sand slab. I expected a little less efficiency but I'll be darned if it does not work...and work well.

When I was building my back shop 25 years ago, I wanted a wood radiant heat floor. But, not much was known about radiant floors back then. The few plumbing supply house that had radiant heat supplies told me that no way would it work with a wood floor. Glad I didn't listen to the "experts" !!!!

Then I contacted an engineer in the radiant floor division of the Hydrontics Institute in NJ. He sent me copies of pages of basic engineering layouts of radiant floor systems and gave me a lot of advise.

I built the flooring system by using a 3/8 plywood subfloor over the joists. Over that I used 1 inch rough cut hemlock boards with 1 inch spaces between the boards for hot water pipes. Then over that I used 3/8 plywood for the actual shop floor surface. All screwed together with 2-1/2 inch deck screws. It worked quite well, but the piping was 3/4 inch diameter - narrower than the rough cut hemlock, so the pipes laid down in the gap with a 1/4 inch air gap between them and the shop floor.

I improved heat radiation by taking lengths of 18 inch aluminum roof flashing and weaving them under the pipes and over the hemlock, then placing a 2 foot length of 2x4 on top of the hot water pipes and jumping on the 2x4 to push the pipe down thus forming the aluminum flashing down into the gaps between the hemlock spacer boards so that the top sides of the pipes were flush with the top of the hemlock spacer boards. That way, the pipes were pushed up into always having contact with the underside of the shop's plywood floor. Plus the aluminum pulled additional heat out the pipes and spread it to the sides were the hemlock boards were.

Final results were that the entire floor was now radiating heat - not just the narrow strips above the pipes - and the plywood floor right over the pipes had come up over 30 degrees. With the heat coming from floor level I could turn the shop temp down. Being warm from the feet up I found I was just as comfortable with the shop wall thermostat set at 64 degrees, as I was at 70 degrees with a typical furnace, or boiler/radiator hydronic system.

And I drive 2 ton cars onto that floor, use steel wheeled car jacks and steel axle stands, all with no problem.

Paul

Why did you think we would try to talk to you out of it? I have heard of others doing this with very good results. There is a company in VT that sells radiant kits and this is one of the install methods they list: http://www.radiantcompany.com/details/methods/legder/

NoSmoke wrote:(The concrete slab is thermally isolated from the ground via 2" Styrofoam insulation).

That part is key.

Rob R. wrote:Why did you think we would try to talk to you out of it? I have heard of others doing this with very good results. There is a company in VT that sells radiant kits and this is one of the install methods they list: http://www.radiantcompany.com/details/methods/legder/

NoSmoke wrote:(The concrete slab is thermally isolated from the ground via 2" Styrofoam insulation).

That part is key.

Yes indeed!

That's what I did with my poured floor for the 2 front bays and paint room of my shop. One foot deep of crushed stone over double vapor barrier to get the thermal mass, then 2 inches Styrofoam over that, then the 6 inch steel mesh to wire down the three zones of 300 foot coils of Wurtsboro tubing, then 6 inches of plastic mesh reinforced concrete over that. No expansion joints in a 22x37 foot pour and only one hairline crack between two of the three zones in that slab.

Paul

I would have denied payment to the so called
house builder that put my fathers factory built
home together using radiant floor heat.

They did a such a poor job of assembling my father house that
I don't recommend them at all to anyone for very specific reasonds
including the infloor heat which was waste of money as it was
improperly installed and too boot we found today that he ringed
the damn laundry room toilet with a loop right around the 3 inch
waste pipe base butted right next to the toilet flange under the floor.

My brother had to replace and repair the toilet piping and if he had not
checked the piping under the joists in the laundry room the toilet flange
repair would have perforated the in floor radiant that was not even
installed with heat reflectors for the entire system; the fools!!!!!!!!!!!!!!!!!!!!!

My father would have been better off with steam heat or radiators for hot
water heat for all the aggravation they caused him.

He could have used a steam boiler the size of large dog crate with no issues
as he has propane for fuel and he would not have required a pellet boiler
which was not needed to begin with if the job had been doen right to begin with.

As for thermal insulation they never insulated or water proofed the basement exterior walls
nor did they insulate the garage slab and it cracked of course because they poured it in one lift
without even cutting relief joints.

If anyone wants to know who it is I will gladly tell you off the board if you plan on buying a
packaged home the fingerlakes and southern area of New York State

Caviat Emptor "Buyer Beware"

The engineering firm set up idea that I read about had a full sized basement that they wanted to fill up with sand applying pex tubing as they went. The idea was a radiant heat/geothermal mix I believe, but regardless, they scrapped the idea figuring the pex tubing would expand in sand when warmed, push the sand away from the tubing and yet when it contracted, not be in full contact with the tubing making it inefficient.

I disagreed.

I did use live sand (which was a NoSmoke story of epic proportions onto its own) instead of dead sand for fear of the sticky nature of dead sand could do such a thing. I figured the live sand would revert back onto the pipe with every tremor the house encounters which here is every time a logging truck goes by, not to mention other shocks that would jar the sand back around the pipes.

As for the entry area where the pex tubing was laid directly under the slate flooring is really nice. We are a shoe-less home so to stand on nice warm rocks after removing your shoes is a nice welcome home treat.

BTW: I made the slate from rocks on our own farm. If I can make something myself, I really try to do so.

Ha-ha! Every inventor has been told it could be done !

The Epic NoSmoke story of how I acquired my sand...

Well I am cheap, super cheap and if I do not have to spend a penny I won't, and while I do have a gravel and sand pit on my farm, unfortunately it was the dead of winter and the ground was frozen solid. I abused my tractor pretty good trying to break through the frost but it was of no avail...

Well my town being as cheap as I am, and it does not use salt but rather sand on the road to get cars up and down the many hills, so all I had to do was borrow theirs. Apparently others have thought of this as well so at the end of the 1/4 mile drive into the pit they put up a gate. Not to be deterred by the padlocked gate, I simply grabbed a few empty 5 gallon buckets, my daughters plastic sleds and a shovel and hiked to the pit. From there it was just a matter of shoveling sand into the buckets, placing them on the sleds and then tugging them back to a car. (3 buckets in 2 sleds)

Yes a car...a Ford Focus to be exact, not the ideal vehicle in which to move sand 5 one way miles from a sand pit to your home in the dead of winter. But with a little ambition, some calculated placement of buckets, I could get 15 loaded 5 gallon pails into the car.

I do not remember how many trips it took, but one time I found the gate open because it was snowing that day and the town was loading sand onto trucks to sand the roads. I just waited until a truck went in, loaded, then went back out before I got my sand unannounced. It was great because it was the only trip I took where I did not have to hike 1/2 a mile to get buckets of sand.

But I never paid a dime for any of it!

wow

ok

Well,I have to say that had I known ahead of time,i would have tried to talk you out of STEALING the sand,because as the story so far has been told & explained,i see no other way to describe your sand "acquisition" than to call it STEALING.~~~~~ Maybe I should reread this entire thread.......... just incase there is a phrase...... Once upon a time..... but that still wouldn't be a good moral story for children to play & pretend.

As one of the larger landowners in town, I am pretty sure they would have let me take a few yards of sand; but I never asked, so I'll never know and thus technically it was stealing. It only goes for $2 a yard here so there was not much value to it, but the town's sand was live and thawed out while mine was frozen necessitating the forced acquisition!

I'll make it up to them though. They are going to be fixing some roads near me and thus I'll let them take the gravel they need out of my gravel pit if they want to save on trucking costs.

Funny story; a few years ago I happened to go down to my pit and noticed a couple of hundred yards of sand was missing, but was not to worried about it. I mentioned it on a farm forum and the people were indignant about it, but here if you wait long enough, you find out who did it. A few months later I got a check in the mail and thus found out who had needed it. Just a farmer down the road who used it to keep his cows from slipping on the concrete coming into his milking parlor.

We don't get too excited around here; after awhile people square up one way or the other.

In MOST cases's... You have the right to the sand in your township anyways, for your driveway in the winter or other small needs, as you are a tax payer and so a small portion of it belongs to you, but of coarse u can't haul tandem loads out lol at least that's the way it works around here, most people are just un aware of it and won't ask the superintendent.

That's the way it used to be down here on The Cape...
Just ask the guy runnin the loader for a scoop...
And it was a big loader...
That was when we still used the dump as a landfill...
Now it gets sent off Cape and burned for electric...
So no more open pit access to sand...