Hydronic floor heat vs. overhead radiant tubes
Hydronic floor heat vs. overhead radiant tubes
(OP)
I'm looking for a very rough estimate on the installed cost of hydronic radiant floor heating vs. overhead radiant tube heaters. The space is a tractor trailer truck garage of about 9000 sf. I understand there are many variables left out but need a rough estimate to give a client. Natural gas would be the fuel. Any ideas would be appreciated. Thanks.





RE: Hydronic floor heat vs. overhead radiant tubes
In my limited experience, overhead heaters >never< manage to heat the floor.
The people who have to stand, kneel, sit, lie, crawl and otherwise work on that floor will worship you for getting them the floor heat.
Mike Halloran
Pembroke Pines, FL, USA
RE: Hydronic floor heat vs. overhead radiant tubes
You application is small Square footage, I'd say go with floor. Overhead manufacturers have all kinds of disclaimers for being X No. of feet away from combustibles, etc.. they are a lot of hose reels, light fixtures hanging from the ceiling and MOST IMPORTANTLY the travelling Overhead Crane which will for sure be in the way of your overhead radiant heaters supports.
Need to watch for close coordination with plumbing, have them use a french drain style between the radiant floor bays in the facility which would lead to a sand trap (you know, they use this sand to soak in the spilled oils), warn the plumbers not to use floor drains, they will be clogged with sand.
Your 9,000 SF will cost about the same if you were to exlude the concrete assuming its a new job.
Go to www.wirsbo.com, they have some nice slab details.
Use condensing boilers, they love the cold water return (90F) temperature from radiant floors, you would be getting 94+% efficiency.
OK, may be not if you are in California, PEX tubing is not allowed there I've heard (there's been an issue between PEX tubing manufacturers and the state of California).
The other thing you can do is use combination CO/NO2 sensors to energize a heat recovery unit for ventilation instead of having the units run continuously in winter. Use radiant ehat as primary heating medium, HRU as secondary. In idea is that if teh air quality is good, no need to bring in outdoor air. And you have yourself a LEED facility.
Good luck
RE: Hydronic floor heat vs. overhead radiant tubes
In-floor is quiet, it's invisible and the floor is always warm no matter what you have in the space.
Square foot cost of floor-mtd about the same as ceiling-mtd.
RE: Hydronic floor heat vs. overhead radiant tubes
RE: Hydronic floor heat vs. overhead radiant tubes
It is sooooo stiff that it is frequently cracked by installation.
I'm with the state of CA, its lousy. There are products that are much more flexible (Onix for one) and easier to install.
RE: Hydronic floor heat vs. overhead radiant tubes
RE: Hydronic floor heat vs. overhead radiant tubes
RE: Hydronic floor heat vs. overhead radiant tubes
RE: Hydronic floor heat vs. overhead radiant tubes
Independent of make-up, exhaust, tailpipe and office areas; I believe a slab design with PEX tubing, good control system and a condensing boiler will run almost 2X the cost of low intensity IR (positive pressure systems). Vacuum tube is slightly more than pressurized.
Waste oil, if available in large quantities and the need to heat an exterior slab for a wash line could help you justify the boiler.
RE: Hydronic floor heat vs. overhead radiant tubes
PEX-B or PEX-C... 8 inches spacing for the tubes in slab,
design a single "cooker" bay with radiant to melt off the trucks before bringing them inside. Insulate under the entire slab for your climate zone and don't be stingy... 2" thick first 4 ft from fondation edge, then 1" thick ...
RE: Hydronic floor heat vs. overhead radiant tubes
The gas fired infrareds will heat the floors and every thing else they are "looking" at. Their design constaints need to be addressed but even with cranes we seem to make it all work out in maintenance shops, wash bays and machine shops.
A rough cost is the retail price of the infrared plus the cost of the unit to have it installed. Figure out how many u need, get a budget from ur locale supplier or rep, times two and there u go, ball park number......
Dont forget that the cost of infloor must include the up cost for the underslab insulation.
D