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shellking_gw

will this gap in floor heat wires be a problem?

ShellKing
11 years ago

They put down the wires for the in floor heat today. I'm not sure what brand was used, but the wires are held down by metal strips nailed to the floor. Then a layer of mud-like stuff was put down.

Looking at it now and it seems like kind of a big gap between the wires and what will be carpet in the two closets. I don't want to hit a cold spot walking between the shower and closet. Is this too big an area to leave without wires? There is 12" between the wires and the edge of the carpet in one closet and 8.5" in between them in the other closet.

Is this acceptable spacing?

Comments (39)

  • live_wire_oak
    11 years ago

    You want the wires within 3" of the edge of the closet. You will have a cold spot.

  • ShellKing
    Original Author
    11 years ago

    this is the part that I find so stressful about this remodel. I looked up installation instructions for this type of heating system and it says to instal 2" - 8" from walls. To me this means the heat will not spread out over 12". So I talk to the tile guy (whose assistant did the job of laying down the wire) and said I was concerned that there was a 12" x 18" high traffic area without heating wires. He said that was okay for doorways. I said I didn't think it was.

    I told him that if he was confident I wouldn't notice a difference in the heat in my floor next winter then it would be okay. He says it will still be warm, but not as warm as the other part of the floor. I said that was my concern, I shouldn't have to notice a colder spot. I agreed that in areas beside the toilet or other non-traffic areas it wouldn't be an issue. But this is an area I will walk on a lot.

    He's agreed to move over some of the wire next to it. And now I feel like I just told him how to do his job. Awkward all around. I find this stressful.

  • jettasmom
    11 years ago

    I can sympathize with your concerns and relate to your comment about it being stressful. You are paying good money to have a heated floor and it is reasonable to expect that you won't notice a temperature differnce in the traffic areas. It's definitely better to speak up now than later.

    I had to have a similar conversation with my tile installer. He ordered a wiring kit and dropped it off with plans to begin installation the next day. When I was reading the info that night, the kit he bought was designed to cover 36 square feet at the maximum recommended spacing of 3". His tile bid was for 70 square feet. I discussed it with him and basically told him I couldn't see how the size kit he bought was sufficient. He said that they usually install with a 3 1/2" spacing and that they weren't going to go too close to the baseboards and vanity toekick and obviously they wouldn't need to install any wire on the sides of the toilet.

    My installer either thought I was demanding that he switch out the kit, or had second thoughts, but he did go and get one that at the max spacing covers 54 square feet. In measuring his helpers did install with a spacing between 3 and 4". I haven't tested it yet as the electrician was just here to install the thermostat.

    I'm sure the tile guy knows more about this than I do, but I think that he was trying to save money on supplies. I looked at one place online that sold just the SunTouch wire and it was about a $70 difference.

    Good luck!

  • weedyacres
    11 years ago

    I have to say that's a pretty sloppy install all around. The most important thing is that the wires are spaced evenly. Even on the wired portions of your floor, there is significant variation. On the RH side of the photo, the wires look about 2" apart, followed (as you go left) by ~3" spacing. Then, roughly in the middle of the photo, you've got that loopy part that's definitely going to give you a cold spot--and right adjacent to some closely-spaced wires, which will magnify the difference. And the spot by the closet definitely needs to be filled in. The heat doesn't transmit very far outward, and your feet will DEFINITELY feel the difference throughout the floor. I can tell your installer has never lived with heated floors himself or he'd know. :-)

    If it were me, I'd have him re-do the whole thing to make the wiring spacing consistent. If you're short on wire, it's much better to cheat the spacing wider than to leave a portion unwired.

    This is what properly laid wire should look like.

    And BTW, see the part near the top door in photo #1 where the spacing is a little wider? That's a cold spot in our kitchen floor. Not freezing, but noticeable every time I walk over it. I should have scootched that first wire over and spread out each of the other ones by 1/8" or so to spread the difference over a greater area. I learned; that was only my 2nd heated floor. :-)

  • GreenDesigns
    11 years ago

    Complete redo time. On his nickel.

  • LE
    11 years ago

    We let our tile installer get away with a gap near the doorway to the bathroom. She said the heat would spread out through the tile. We have a cold spot that my foot hits every time I walk in there in the winter and it irritates me every time. Every. Single. Time. It is not like one of those cosmetic things that you obsess over and then don't notice later.

  • ShellKing
    Original Author
    11 years ago

    After reading the manufacturer's install directions we could find a number of things that weren't right. I'll update when we know more.

  • davidro1
    11 years ago

    it takes a lot of arithmetic to figure out the layout of loose wires. This is why mats are better. Even though mats cost more, they give you a prelaid pattern, modular and which can be dis-assembled if need be. You can undo a strip or two of any mat in order to gain the advantage of a loose wire, whenever you want to go back to loose wire laying, if you need to do this for any reason.

    Loose wires sometimes take a DIYer a week or two to figure out. Even if you are a DIY you wouldn't want to take an extra day or two to figure it all out a second time and redo it all. Or would you?

    ShellKing, if I had to take a "best alternative" approach I would move the first seven rows of wires over. Rows 4,5,6,7 are too close. Before advising any other approach I'd like to see another picture. Your space is bigger than the image shown. Post a photo of the room wall to wall.

    In the picture posted by weedyacres, loose wires were laid down in 12' lengths (or longer), which is long for a wire that will expand and contract slightly in every cycle. An argument can be made that it would have been wiser to lay the wires in a pattern that made each length only 6 or 8 feet long. It's more looping back and forth, which is more work, which costs more and takes more planning too. Remember that trains go ticketytick on the track because of the obligatory spacing of the rods, because steel rods lengthen and shorten depending on their temperature. The same thing happens to straight wires. And to any other material that is continuous: Thus they install wall to wall expansion joints (flexible rubbery) in any tiled floor that is huge. Otherwise the tiled floor bends up like a balloon when the sun shines on it. Wikipedia: "failure mode in pavement materials, primarily with concrete, since asphalt is more flexible. Radiant heat from the sun is absorbed in the road surface, causing it to expand .... Similarly, rail tracks also expand when heated ... common for rails to move laterally, often pulling the underlain railroad ties (sleepers) along " So, long long straight lines of wire might lead to early failure. This is just F.Y.I. and not related to the bathroom of the OP.

    Hth

  • gr8daygw
    11 years ago

    lori, we have the same thing in our bathroom, the heating coils do not go up all the way in front of my vanity and a couple of other places and the tile is like standing on ice cubes. On my husband's side it does run up to the edge. Like you say it does irritate you every time and they even DID use the mat type, I just think they skimped on it and didn't want to add another one since the job was priced to the dollar and that's what we paid. I would rather have paid for another mat. It does wake me up in the morning stepping on that icy spot in the winter!

  • Tim
    11 years ago

    I respectfully disagree with the above notion that cables are difficult to calculate or figure out for a DIY'er.

    I've done two bathrooms in my house - 80 sq ft and a small 30 sq ft room both with NuHeat cables. Was as simple as pie.

    I drew the room out on graph paper to scale, and planned the layout of the cables. 3" per 1/4" square on the graph paper made it easy to ensure proper spacing of the cables, and counting things up allowed me to confirm square footage coverage and overall length of the cable I needed.

    Sure, ordering custom made mats would be easier, but way more expensive.

    Don't buy your cables from a tile shop BTW, especially a fancy tile shop. They mark them up significantly higher than if you buy through an electrical supply place. Don't buy this stuff (or anything else for that matter) at the big-box stores. You're usually going to find better prices and higher quality at smaller specialized supply shops (i.e. electrical from an electrical shop, plumbing from plumbing supply etc.)

  • kendog2
    11 years ago

    I agree with TorontoTim that it's important to shop for the best price on heated floor systems. We purchased ours on Amazon from Warming Systems. It covers 30 square feet and cost $189. It is listed as a cable system but they sent us a mat with the cables imbedded. I'm not sure whether this was an error or not but it was a pleasant surprise. For comparable systems, I found prices ranging up to $700.

    Thanks to everyone who has contributed to this conversation. It is invaluable information.

  • ShellKing
    Original Author
    11 years ago

    Almost 2 weeks later and still no agreement about if this installation job is correct. He's coming back in two days to convince me that it's good enough. Here are more pictures.

    Here is the wire running under the vanity, which has now been installed:

    The wires should be spaced 1.5" - 3" - 1.5" - 3" apart from each other according to the manufacturer's installation directions. Here's a picture showing them at 1" spacing for a few rows at a time.

    And then there's the water closet:

    The two doorways on the left are carpeted closets. Notice the wires do not extend into the doorways very much. There is 8.5" of space in the first doorway. I'm afraid this will lead to a cold spot:

    Here is a link that might be useful: Installation Instructions

  • weedyacres
    11 years ago

    Oh my GOSH, that's the sloppiest install I've ever seen! I stand by what I said above. CONSISTENT spacing is what you need.

    Are you sure the manufacture said to alternate 1.5" apart with 3" apart? That doesn't make any sense, as heat goes equally in both directions. Can you type in exactly what the manufacturer's instructions say about spacing? I think you may be interpreting it incorrectly.

  • ShellKing
    Original Author
    11 years ago

    I wish I was reading the directions wrong and the correct info said to slop it all around because it won't matter once the tile is on top. ha! :)

    Here's what I'm looking at for directions. (the entire set of directions can be found on the link on my previous post)

    because this floor is above a non-heated crawl space, the directions call for Alternating Heating Cable Spacing.

    You'll notice the directions are also pretty clear that the wire should not extend more than 1" beyond the outside edge of the strapping. You can see in my photos that it clearly extends many inches beyond the strapping in lots of places. Although I'm less concerned about this because I cannot see an obvious way that this would effect the way it will perform once tiles are installed. It is however one more thing that I see isn't correct in regarding to the written instructions.

    What to do now? Installer says it's fine.

  • kirkhall
    11 years ago

    Fire him, pay him no money for that job.

  • davidro1
    11 years ago

    You must have sent these photos to the manufacturer. They have a customer support department. What have they said so far? OR, are you relying only on anonymous internet people to guide you?

    In the photos i cannot see the end strip ("Strapping") that holds the wires stiff. It works well as a gauge to get the distance right.

    In the WC photo, I think I see that wires go into a final loop, spliced together. I think I see that the cable does not return home. Can you confirm this? It will be a big factor in my decision making. Show it to the manufacturer. What is the white stuff over the splice? Or, am I reading it wrong?

    There will be heat differences where the wires are close and far apart. It is better to re-do the spacing than not.

    Whether or not you want to use the same person to do the respacing, is your call.

    you wrote that the vanity had been installed. To tile the floor involves removing the vanity once more.

  • davidro1
    11 years ago

    should have written that I cannot see the strapping strip in all cases.

    in any case, it is a gauge at the ends, and works best when it helps tighten the wire instead of letting the wire flop around loosely.

  • ShellKing
    Original Author
    11 years ago

    I called the manufacturer and spoke with customer service. I described the install and asked them specific questions:

    Q: Can the wires be installed 1.5" apart from each other for 7 adjacent rows?
    A: NO. It will overheat and may fail.
    Q: Can the loops extend past the strapping as much as 7 inches?
    A: NO. It must not extend more than 1 inch
    Q: If there are no wires for an 8 inch span, will I notice an absence of heat?
    A: YES. The wires must be installed 3 inches from each other or the edge where you want heat.

    Here is a photo where I have tried to highlight the location of the strapping strips.

    In the WC photo you are indeed seeing the end of the cable, the "tail splice". It just ends. In reading the directions it says that it doesn't have to return to the beginning, but that the floor should be notched so that it won't stick up and a plastic piece that was included in the kit should be fastened over it to keep it down. Yet another thing that wasn't done per instructions. On my floor it's sticking up despite the extra dollop of goop he put on top.

    The tile professional's assistant did the job. At this point I'd be happy it the main guy redid the job. He's already been paid a 50% deposit on the whole tile job.

    The plan was to tile around the vanity. The cabinet guy and tile guy said it either could go first. The marble slab guy wanted the vanity installed before he templates the top. The tile guy wants the slab installed before he tiles the backsplash.

  • davidro1
    11 years ago

    ok, got it, it's a cable that doesn't need to return.

    The overuse of strapping strips in the middle is another big clue that this guy doesn't know what he is doing. There are more clues. But, it figures that you have not reached the end of your rope with him yet. YOU ARE SEEKING FACTS AND KNOWLEDGE. GOOD FOR YOU. BUT... I doubt you will get satisfaction using your current style which is fact-based. NO matter how much you learn and then think you can teach this guy, you will fail because he will run circles around you; he has more experience than you have, in running circles around problems instead of learning and applying the knowledge. It's real easy to install loose wires if one takes the time to figure it all out once and for all. This is why the manufacturers have phone lines and like to receive incoming calls. Ask him how many times he has called for questions to be answered.

  • ShellKing
    Original Author
    11 years ago

    The strapping strips are a bit of a mystery. The regular instructions say to place them much farther apart -- but . . . then there was a paper insert in the box that said to put them every 6" Weird, huh?

    At this point I'm trying to decide what to do next. Tile guy is coming over day after tomorrow. I hope we can reach some sort of agreement/compromise that doesn't void my warranty and ensures that I don't have cold spots.

    After that, he's supposed to install my tile.

  • davidro1
    11 years ago

    there was a paper insert in the box that said to put them every 6" Weird, huh?
    This is worth a phone call back to the same people you spoke to yesterday for technical support. I'm sure the mystery will be cleared up in no time.

    Meanwhile, back to the bigger problem: they guy who you are investing in didn't catch this and figure it out. So, all of the "what was he thinking" that comes next all leads to the same conclusion that you resist wholeheartedly. Stop falling in love with a loser. He is not the right kind of learner who will pick things up from you just because you managed to go get some basic knowledge. In fact you still don't know much yet, about wires. How many times have you called the company for information or training? Your guy, who you have invested in, has done ten or twenty things wrong, and is not rising to the challenge of giving good answers NOW. Hope against all hope that you will reform him in one next conversation. Dream on. Or, change your approach to him and to contracts in general.

    Who cares how much money you spent so far? It's irrelevant to the future course of action, if you stick to the technically right thing to do.

    What is the right thing to do now, technically? Hard to say, because there is a lot of information missing from your descriptions so far. Be prepared to call the manufacturer back more than once. At least twice. Once to get a sense of all the technical things you need to know before you get your "invested" guy on the line with them, and once again when you observe his back and forth interaction with them over the phone.

    How many people invest more money in order to protect the bad investment they made earlier? Billions. So you are just as human as everyone else. But you are not tough enough, in my estimation. The guy in whom you invested X dollars so far has ruined that investment. Move away from him. He will waste the next dollop you invest in him. My opinion.

  • _sophiewheeler
    11 years ago

    The only fix for this is complete removal and starting over. And that vanity should never have been installed either. It goes in after the tile is done. If you're having this many problems, I really think you need to take a look at what was done previous to this. I'd suspect you also have problems with waterproofing the shower and a whole host of other detail oriented portions of the project.

    PUT A COMPLETE STOP TO THIS NOW!

    Or you may be completely wasting your money here. Show us some pics of how he's done the other portions of the remodel. I don't think you want to let this guy anywhere near your project. You need to determine if you have worse (possibly structural) issues with the rest of his work. It's better to find out now than a few years down the road when the leaky shower creates black mold coming through an adjacent room.

  • davidro1
    11 years ago

    There are other things wrong with the work done. Things visible in the photos you posted. Just telling you, so you know there is more than what you have asked about, therefore more than you think you have learned in the last day or two. This is one reason not to bother trying to educate the person in whom you have invested money so far. It's the blind leading the blind, no matter how much you learn on your own. With what little you do know now, spend time and effort cornering this guy into saying things that prove to you why you should drop him.

  • davidro1
    11 years ago

    even 18" spacing is overkill, if the wires are taut between the two strips at the end of each loop.

    But the lesson learned here is 1.) that there are a batch of easy-to-learn things, and then a whole big bunch of not-easy-to-learn things that all interconnect. And 2.) that the guy, into whom you are investing your hopes and your money, didn't even know the simple stuff. Now, instead of telling him honestly what you found out, corner him in various ways until he lies to you a few times and then see if you like him. Ask dumb questions and pay attention to his answers.

    Toronto Tim posted that it was easy to lay loose wires. For some people it is. I link to his kitchen reno project below. It's pic heavy.

    Here is a link that might be useful: Toronto Tim kitchen reno done

  • ShellKing
    Original Author
    11 years ago

    When we met this morning, he still insisted it was fine. I showed him the instructions and shared with him the info I got directly from the manufacturer.
    Davidro1 was correct that 'teaching' this guy how to do it correctly wasn't going to work.

    We told him to rip it out; we are starting over. He will not be installing the new one nor doing the tile work.

  • davidro1
    11 years ago

    hope you are glad you did all this research to get to the bottom of it all.
    There are more concerns that need to be double-checked. Your next tile guy will know more.

  • weedyacres
    11 years ago

    Good for you for putting your foot down and insisting on correctness.

    I'm still puzzled at why the alternating spacing is recommended. It doesn't make sense to me why heat would travel any differently over a crawl space than over heated space. In my experience, closer spaced wire spots are warmer than farther wired spots. Can anyone enlighten me?

  • davidro1
    11 years ago

    a regular variance of this amount of space will not make a big heat difference on the surface of the tile.

    the gauge strips (strapping) have nodules at regular intervals. Using these nibbies is what makes this alternating spacing. As the wire goes back and forth looping around these nibbies, you skip one of every 3 nibbies and this is just enough to come close to the ideal of a regular spacing.

  • weedyacres
    11 years ago

    But why would it be recommended over regular spacing?

  • davidro1
    11 years ago

    the nibs on the straps make it a best-alternative-to-the-real-way-it-ought-to-be-done. It is "recommended" because it uses the straps and the nibs on the straps. Otherwise, you can thinset the wires down with regular spacing if you wish to do so and know how to do it.

  • ShellKing
    Original Author
    11 years ago

    And I think the theory is that tiles above an unheated crawl space need more wires than tiles above a heated room in order to provide the desired amount of heat. Just guessing.

  • davidro1
    11 years ago

    yes, it's because there is more heat loss.

  • weedyacres
    11 years ago

    That would explain why they recommend putting them closer together, but not why they recommend uneven spacing. In my experience, the areas with wider spacing will be noticeably colder than the areas with closer spacing.

  • davidro1
    11 years ago

    The distance is a 3/8" difference. I already explained that this is negligible.

    The uneven spacing is to make use of the strapping's nibs when looping the wires back and forth.

  • weedyacres
    11 years ago

    That's not how I interpret the instructions OP posted. In 6a each row is 3" from the next. In 6b, rows 1 & 2 are 1.5" apart, rows 2 & 3 are 3" apart, rows 3 & 4 are 1.5" apart, etc.

    What's the 3/8" difference you're referring to?

  • davidro1
    11 years ago

    1 1/8 inch spacing is the regular interval (ideal) which the clips on the strapping cannot handle, so it gets moved over 3/8", in alternating directions. In any case, the manufacturer claims that the heat ends up being spread, in "good enough" fashion. I'm sure that nobody will claim it's ideal.

  • Tim
    11 years ago

    Spacing of the strips to hold the cables down just needs to be reasonable. Here's the work I did (my first heated floor install) in my 80 sq ft bath. Was very simple - just follow the instructions. On a wood floor the strips are easy to screw down. In my basement bath I installed directly on a slab which was a little more difficult as hot glue doesn't do much to hold the strips in place.

    Ultimately the strips are only there to keep the wires in place till the thinset is laid on them. I recall the spacing of the wires is 3 inches. NuHeat cables with the NuHeat Harmony thermostat which installs in the wall in a standard 2 gang switch box.





















  • ShellKing
    Original Author
    11 years ago

    Now *that's* what a nice even layout should look like!