Heating Concrete floors with no insulation

Rob Blair

I have a project where they are doing a commercial type floor poured on the corrugated metal panning for each floor system. The ceilings are going to be exposed and the corrugation would be hard to insulate because of its up and down "U" shape. I am concerned with the heat radiating from both the ceiling and the floor making control difficult. What would you suggest?

Thanks,

Rob

Rob

Rob Blair

Heating Concrete floors with no insulation

I have a project where they are doing a commercial type floor poured on the corrugated metal panning for each floor system. The ceilings are going to be exposed and the corrugation would be hard to insulate because of its up and down "U" shape. I am concerned with the heat radiating from both the ceiling and the floor making control difficult. What would you suggest?

Thanks,

Rob

Rob

singh

Not certain , But I thought that leaving the Q-decking exposed like that was against fire codes. They should be sprayed with fire retardant.

If not , well I don't think there is much that can be done for control.

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

hot_rod

I did a residence last summer

that was a poured slab on "span-deck". The bottom side was spray foamed, although it was a dropped ceiling with sheetrock below.

Installing tube was a challenge with all the slots:) After consulting with the structal engineer we put mesh on top of the panels to help keep the tube from getting damaged where it crossed the channels.

I wonder that you might find a spray foam or coating applied over the foam to provide the fire protection required?

hot rod

Rich L.

Floors

Are there going to be floor coverings on the top side or just finished concrete? I haven't tried this before Rob but I wonder if you could use a roll type flexible (not bubble wrap) insulating product. I'm thinking the black stuff with the foam in the middle about 3/4" thick. I think it's designed to go under slab on grade and I personally won't use it for that application myself, but it may work here. Especialy if there isn't carpet over top. If you could get enough resistance to keep the heat moving the right direction you might be ok. Just some random thoughts!

Good luck, Rich L

Rich L.

Spray

I'm assuming spray foam on the underside is out if it's going to be left exposed?

jp_2

spray cellulose

I've seen stuff that looks a lot like cellulose, this was sprayed on steel girders and ceiling.

Rob Blair

No insulation on the bottom. They want the exposed steel. I will see when I meet them on Monday.

Thanks,

rob

Dave_49

maybe

Rob,
Have you concidered insulating between the metal and the concrete? The corrugations might cause a problm. Some super tough foam might span the corrugations, or the bubble wrap stuff might conform to the metal panning. Just a thought.
Dave

Gordy

How thick ??

Will the concrete floors be ? Sounds like with the limitations on the insulation, your only solution may be an insulated over the top system. All though a radiant sandwich sounds cozy. The fly wheel could be a dog chasing its tail.

Gordy

devo

Insulation of metal decking.

I am in the process of constructing a building with exposed metal decking in the lower level. The solution I am proceeding with , will be, to cut individual insulation strips (XPS ) to be placed between the risers of the decking and then to proceed to lay down full sheets of XPS on top of this ( to eliminate any and all pressure points). I will then lay down re-bar/ mesh and attach my tubing to this and complete my over-pour. The upper and lower levels will both be heated with radiant floor.

Rob Blair

This is when I think that floors may not be the right heating ..

place. Possibly walls or panel rads. With the house being insulated with ICFs the load is very low and with no insulation between floors I am afraid that heat will be radiating into both floors causing t-stat confusion.

I will have to really look closely into this.

Thanks guys,

Rob

Weezbo

ask them to consider the need rather than the want.

today they don't want insulation soon as they see the energy bills all of a sudden it will be Your Problem.
the thinking is incongruent with current practice.
basically you need to try to educate them as to the future benefits vs the immediate desire .

if they, who ever they are ..want to stick to their guns and wont budge, even after showing them new products and intelligent design, do your best to get away from them, now.

it would end up all wrong for you.

why did they hire you anyway? if it was to tell you what to do rather than for your best considerate effort
they hired the wrong person.

i can almost describe the project sight unseen...

remember insulate , ventilate and heatilate mantra...

i have seen some very good work overshadowed by lack of insulation and/or proper ventilation... the cost is not in what you do today it is in the price of owning the choices that you make. ever climb about in red iron webbing in the winter in a commercial building built with no consideration for insulation 'Details'?

ever see one of the fuel bills?

ask any of the lease holders about the comfort level?

there is what i am looking for... Fools Gold.!

that is what these bright ideas are like...people buy into it Rob because That is what they Want to Hear or see,

you just don't want to have to be the fall guy when they figure that out.

Steve Eayrs_2

pan-deck slabs

Don't think you will find an engineer that will approve of insulating beteen the metal and concrete. THey want the concrete to adher to the metal and count on the corrigations for structural too.
We have been invlved in an ongoing condo project for a number of years, that involved a pan-deck on the second level. We have been using screws/clamps to hold the tubing to the metal. THe lover level always is sheetrocked, but most units don't have insulation above the rock.
I protested on one unit. They insisted they put 2" of wood on top of the concrete floor, (hardwood plus two layers of 3/4" plywood). When I told them it would take R38 below the floor to offset the downward load, they blew insulation inbetween the sheetrock and metal, and got about R40.
This is the first winter and it works fine. Just as long as they don't think they can turn down the thermostat and expect any kind of quick recovery. We used Tekmar TN4, and slab sensors, etc... and I am sure that helped as well.

In your case, with not even sheetrock on the ceiling, I would look close at the heat loss in the lower level. It may work if its a sizable load, compared to the upper floor. If its not a big load, it will probably be 80deg, before the upper floor reaches 70.

Steve

jp_2

make all floors ceiling radiant

then the warm floors will be just a perk.

Rob Blair

Thanks Steve.

That was my thought, that the structural aspect of the decking would be compromised with the insulation. The more I am leaning towards panel rads or radiant walls.

Rob

Rich L.

Interesting JP

Radiant ceilings. Rob could you design this as a radiant ceiling job? Use this "floor" as the radiant ceiling, control it as a rediant ceiling to condition the space below and as a by product - benefit get some floor warming for the space above?

Tim Weaver

exposed steel....

I did one like that; they left the corrugated deck showing below (bar joists) and stained the concrete on the topside. Both upper and lower areas are heated, constant circulation and outdoor reset, and it works well. Pretty much open like a big loft; the supply water is only 115 at 0 degrees design temp.