I too am looking at a warming cable system for my basement. I am going tto use the warming tiles system with the alternate spacing ( 1.5"/3") over a concrete slab. The slab is 13 yrs old with a few "hairline" cracks. No vertical deflection. The area I am looking to heat is approx. 400 sqft. including a bathroom and kitchen area. The finished floor will be tile.

I would like to insulate the slab to reduce heat loss. HD has easymat but it seemed expensive and it doesn't seem popular here. HD also suggested using a cork underlayment to insulate and act as a isolation layer.
I am thinking concrete, sealer (red Guard)? 1/4 or 1/2" cork underlayment, warming cable, thin set (to cover the cable), thinset to install the tile.

The only thing I have do so far is buy the heating cable, so looking for advice or suggestions.

Thanks

The redguard will not work as as a crack isolation membrane without using the mat that goes with it, forget the redguard and install 1/4" easy mat using thin set, not the peel and stick, costs about 1.20 sf, this is the 3mm thick

Hi JCR, I moved your post to it's own thread. The other thread was quite long and over a year old. Just a note, you should always start your own thread for your project.

The Warm Tiles spacing at 1.5" and 3" alternating was designed to be installed directly to the concrete for heat loss reasons in a direct wire application. If you introduce an insulating layer then you should be installing it at its normal spacing of 3"

There are a few methods that can be done for your type of installation depending on what products may be available to you. Where are you located?

As for the RedGard, it is a crack prevention membrane and does not require the use of the mat for that purpose.

Your heating system is quite large and will require the use of relay kits. Be careful not to go over the maximum amp load (24A)for the relay based on the number of kits needed.
A quick observation based on your square footage looks like you would need three 240V kits to do 400 feet for alternating spacing. That puts you over the max amp rating.

You may have to split up the heat zones to run indepentently of each other.

Thanks for the tips. The floor area is 400 sqft - approx 90 sqft for cabinets and appliances. I am located in Canada but am close to border so I have access to US products if they will help.

I am going to use two cable kits with two thermosats. One for a bathroom and hall area and one for a kitchen area. I have bought the 240 V system and have room on the panel for electrical. The one system is just over 10 Amps and the other one just less.

I am looking into a cork underlayment to act as thermal barrier as well as crack isolation. This is for basement application. It was recommended by Home Depot but any advice would be appreciated.

Thanks

I'm somewhat confused as to how two kits from Warm Tiles are going to cover 410 sq. ft. of heated area. Did you buy these kits from Home Depot? What's the actual brand name?

I don't know of any cork underlayment that would accept a heated floor system let alone a tile installation.
Have you read the installation requirements for your heat wire system?

No offence to the staff at the Depot, but be cautious as to their recommendations. They are not professionals by any means.

The kits are from easy heat. "Warm Tiles" The kits are
DFT 2195 which covers 185-204 sqft with standard spacing or 139- 153 with alternate spacing. Draws 9.6A
DFT 2215 205- 225 sqft with standard spacing or 154-169 sqft with alternate spacing drawing 10.7A

The cork underlayment is from cork direct. They say many people have ordered their underlayment for just this purpose.

Did the manufacturer of the cork specify an installation guideline for radiant heat wire over the cork?

I did look back thru one of my current technical specification manuals on tile installations and there was a specification for cork underlayment over concrete, but nothing related to cork,radiant heat and ceramic tile.
The cork specified was 1/2" in thickness.

I would suggest you speak to Cork Directs technical department and get the installation specifications from them for the type of installation your trying to do.


Keep us up to date on your progress.