I live in NY where it's cold, and I have a question here that I'm literally afraid to ask. I have a contractor doing a new kitchen for me and he's almost done and has 80% of his money. The kitchen is 12'x17' and, unlike the rest of the house, sits on a slab extension out back (there's a full basement under the main footprint of the house, which is 90 years old, and this kitchen extension is an appendage off the rear).
The extension was actually pre-existing from about ten years ago when the previous owner put in a laundry room and a few walk in storage rooms there. Anyway, my goal was to have the entire area over the slab gutted (12x17) and make it our new kitchen, with ceramic tile floors, and have radiant heat.
Here's the deal... we're almost done, the contractor put in the radiant heat tubing long ago, laid the tile done weeks ago (but never hooked up the heating system to the boiler till now) and has continued to build the kitchen and is almost done with everything.
But yesterday, they finally hooked up the radiant heat to the boiler, and there is bad news. After running it for two hours at 180 degrees the damn floor is still cold... and the return water is barely luke warm!
I'm starting to worry that this whole damn thing has to be jack hammered up and redone -- an unimaginable thing given the amount of time we've been without a kitchen (my wife will not survive this if it's true!).
My question is, based on the original requirements I gave, did my contractor do everything right?
First, since the new kitchen is on the north end of the house, while radiant heat sounded like a good idea, I warned him profusely that it gets cold there... and wanted his assurance that the system he installs had plenty of power to get this space warm and keep it comfortable at a reasonable cost.
These were the steps he took --
1. The whole heating project was done by him with direction given by his "plumbing and heating guy"
2. First, he basically reframed the whole extension (12x17) because it was poorly built by a do it yourselfer, insulated it with the best new stuff, and put a new roof on top... this part seems good ... you can definitely feel that the above ground part of this kitchen extension was done right;
3. Now for the slab and heat, where I'm really worried -- first, although he was able to jack hammer away the very poor concrete laid by the previous owner, there was some incredibly hard concrete below that that made it impossible to go any more than 2 inches deep (the house probably had a patio or landing out back originally, the house is 90 years old)
4. With the slab cleared down to the 2" depth, he said "to be safe" he'd put in 50% more "tubing" than would normally be required for the space - this was to address my heating worries - and he didn't lay the tubing under the 24" cabinet perimeter. Is it correct to use 50% more tubing than is normally necessary?
5. Ok, this is what I'm horrified of - he didn't insulate the slab. Originally, he said he WOULD be putting some insulation on the slab, and then lay the tubing on top. But after it was all done, with the rest of the floor poured over it and the tile man had laid his floor and had gone -- after that -- I asked him about the insulation below, and he broke me the news -- "we couldn't put the insulation bed under the tubing because that would have raised the floor height too high -- you would have hated it."
Shocked and a bit worried about the lack of insulation on the slab, I asked him if that would affect the ability to heat up the room satisfactorily or create a heating cost issue -- he said "no, it won't be an issue, don't worry about it."
But again, since that conversation, it seems like he's been putting off getting the heat hooked up to the boiler forever, and here I am today --- with this dilemma.
Worried about the issue last night, I called him and he said he'd come over and talk about next steps with me today. He's mentioned a few things, like insulating the perimeter of the slab (outside the house), installing a stand alone water heater in the basement just for the extension heat (my 80 year old boiler, while it heats the main house fine, might no be well suited to handle this radiant area he says)... so basically, he's talking about plan B's with me now.
My question is this... is NOT insulating the slab below the heating tubes a fatal flaw ? that dooms any solution short of jack hammering the whole place and starting over?
Thanks for any assistance.