Elk thermostat suggestions

I am looking for suggestions on a thermostat to work with my Elk M1.  I've been searching the forum but either haven't found the answers I'm looking for or they haven't been asked yet.  Here's my scenario:
I'm building a new house and have been buying (home automation) parts in advance.  So far I have purchased an Elk M1 Gold, Elk M1DBH, Elk M1XIN, Elk M1RB, Elk M1XEP, ISY 994i IR/Pro.  My new home has all of the windows/exterior doors hard wired back to my Elk panel.  I also purchased 2 Nest thermostats but I'm thinking of returning them if they won't do what I'm looking for.  Here is what I'm looking for in the thermostat:
1.  Have 2-way communication with my Elk.  By this I mean I would like the thermostat to trigger rules in the Elk in addition to the Elk being able to control the thermostat.  For example I would like a rule that would check all window sensors when the A/C or heat is turned on and speak a warning (or perhaps something else) if a window is open.  Or I would like a rule that will alert me somehow if someone manually sets the temperature below (or above) a threshold I define.
2.  If possible I would like the thermostat to also work with my ISY.  This is secondary to the thermostat working with the Elk.
 
I prewired cat-5e between the thermostat locations and the Elk panel.  I'm also planning on using Insteon for all my lighting.  I would rather not use zWave or ZigBee for the thermostat communication.  Does anyone have any suggestions?  Can what I want be accomplished with the Nests?  Thanks in advance. 
 
-Brian
 

If you have the ISY, why use ELK triggers?  Home automation programming is more powerful and versatile in the ISY than using ELK rules.  Plus you're opened up to other t-stat options.
 
I have an older Venstar Insteon t-stat that has been pretty much bullet proof.  I do not even use the program options the t-stat offers.  The ISY controls all (or I do with my smart phone.)  You will need to purchase the ELK module for your ISY.  With this, the ISY knows everything the ELK does and can make it do anything.
 
When I leave the home for a day, the ISY arms the ELK and adjusts the t-stat to save energy. When I return, the t-stat is turned up.  It also turns the t-stat down when I retire at home at night.  If I'm gone for more than a day, the ISY puts my house in Vacation mode, even if I did not arm it that way.  But it has been a fail safe when I'm on vacation and I loose my Internet connection (which has happened during temporary power outages).

I don't have any suggestions but I am interested in what you end up with because I need to make a similar decision with slightly different requirements. What I need is:
 
1- Control of 3 different systems from multiple locations. Must be full view and control at the remote locations, not just select from predefined presets.
 
2- Voice feedback every time the settings change regardless if it is done manually or programmatically.
 
I used to have RCS serial thermostats controlled by Stargate LCD keypads and that worked perfectly. I switched to NEST for looks but using iPads for remotes has let me down too many times... either the iPad decides to lock up or have a Wi-Fi problem or else my ISP is offline whenever I really need to make a change in the middle of the night and I'm 2 floors away from the main unit.
 
I'm thinking of using HAI Omnistat 2s with an M1 to get back to serial since those have a slave Tstat option but I'm not sure if Elk rules and voice commands are going to get me what I need. I'm also thinking of returning to the reliable Stargate setup and just get a newer generation of the RCS Tstats. I wish RCS would come out with a more stylish serial thermostat that looks like a Nest or Ecobee.

@sanders2222,
I'm not opposed to having my thermostat work with the ISY.  In fact I'd like to have this capability.  But more importantly I want changes made locally to the thermostat to trigger home automation events - either on the Elk or the ISY.  While the things you have done with your Venstar and ISY sound good, that type of control sounds "one way".  I.e. it sounds like the ISY is controlling the thermostat.  I want to be able to create a rule that says (for example) "If the cool set point is set below X threshold, send a notification to Y" to notify me if my kids are playing with the thermostats again.  Will the Venstar allow this type of control with ISY/Elk? 

I use Elk with Zwave and have the RCS TZ45. I've also installed this setup for a couple of others as well - no issues.

I have an Aprilaire 8800. It works with Elk (and can be controlled by the ISY with the Elk module). It requires a few piece to make it work, but its a lot more attractive than the alternatives and works extremely well.

First, I agree that the ISY is the better choice for rules/programs vs the Elk, and that having the two communicate via the Elk module for the ISY is a good idea for many purposes. Thermostats, though, are in my view a very big weak point for both in that neither communicates directly with modern stats such as the Nest. To do that, you need a stat that either speaks to the Elk (old technology that I find less reliable than what is available now) or uses Insteon / Zwave for the ISY. To use a Nest, Ecobee, etc., as you describe you need a third party device and programming such as Homeseer or a Raspberry Pi.

I had Homeseer doing what you describe in a previous home via the Elk. It worked well, and saved us quite a bit as teens in the house at that time would leave windows open all the time. Now, I have switched to the Nest am am very happy. Have Homeseer talking to it, the ISY and the Elk and it allows for fairly powerful programming. But the only major reason I need Homeseer in my system is to make that thermostat connection.

One thing that would be a game changer for me would be if Elk allowed keypads to act as remote thermostat controls rather than just let you pick a pre-defined set point. The keypads have up/down buttons and a display so everything is there to implement a remote thermostat control.
 
As it is neither Elk nor ISY provide a solid native thermostat solution so you really have to have something like Homeseer or Stargate involved... especially if you need thermostat actions to trigger other events or speak or text changes in real time. Glad some folks are pleased with the Nest thermostat but I just haven't been happy with the reliance on Internet connectivity. It always seems to be offline when I need it the most.

I'll have to double check, but I believe the touchscreen keypad lets you set the thermostat temp.

Thanks everyone for the replies.  I've been leery of using a PC solution (like Homeseer) to "tie" everything together just because of the extra (and unnecessary) overhead a full blown PC brings along with it (vs. a "simple" controller like the Elk or ISY even).  I'm concerned about a PC locking up causing rules not to fire when they should.  However if something like Homeseer can do what I'm trying to accomplish, and even let me keep the Nests I've already purchased, then it's worth me looking into once again. 
 
Speaking of Homeseer...it seems like there's some overlap between its functionalities and those of the ISY or Elk controller.  For instance, I believe the Elk, the ISY and Homeseer could all control my Insteon devices.  In that case, where would the lighting logic be stored?  Would that answer just depend on personal preference?  I just don't want one device to step on the other ones.

I place almost all lighting logic in the ISY.

My basic approach is to have the Elk focused on security, and I also use extra zone inputs for monitoring contact closures that can be easily hardwired back to the panel. I also use the outputs as on/off "state" variables for a few things, largely because I'm familiar with them. But I find its rules engine less powerful and more inconvenient to access than the ISY, so I have only basic zone- and output-related rules there. It is rock solid as a performer, though, so I am happy to have it as my security system.

I use the ISY over Homeseer for most other rules/programs/events for two reasons: First, the low power consumption along with lack of moving parts and complex OS you mention (no hard drive, for example) makes it a good choice as part of the "backbone" that controls the house. I have gone many months without touching either for any kind of maintenance or updates, with no issues. Once you get them stable, AVOID the temptation to update to the newest versions of things, unless you are sure you can revert back AND have ample time to tinker with them should you need to do so. I tend to do so now only around this time of year, when I take a week or so away from the business and am just puttering around the house. BTW, I have the ISY, the Elk, the Fios ONT and the house router and switches all on a dedicated circuit that is backed up by a 48V inverter with 110 AH of battery backup (a pellet stove and the low power Homeseer computer are also on that, as we have an electric heat pump for main heat). That setup has allowed us to go through many nights with the generator turned off overnight during multi-day power outages, keeping everyone happy and entertained while saving much on fuel. But I digress...

The other reason I got away from Homeseer was a horrible experience with HS2. I was a raving fan of HS1, and many of course did not have my experience with HS2. But its release also coincided with HS's infatuation with Zwave, and as an Insteon user that sort of left me reliant on third party plugins. Also, it would lock up on me every few days or weeks, reducing the WAF considerably. That pushed me into relying on just the Elk and ISY whenever I could, and I found that I enjoyed having a system that "just worked". I "upgraded" to HS3, but that was also a terrible experience as many plugin authors took forever to make the move and have plugins available. So, I just shut it down for quite some time. I have more recently put it back into service to gain the interface discussed above, not because I needed it for the main Nest thermostat, but rather because I hacked a 2nd pellet stove to work with a 2nd Nest, and needed the interface that we say you need. I must say, though, that HS3 is now running as stable as my old, original HS1 of many years ago and for the use I have for it (non critical) I am very pleased. But I would also be reluctant to use a PC for mission critical functions in the future. I may play around with HS to do some things like talk to an Amazon echo, or even for the things you describe (speak / text a warning when windows are left open). But it will not become part of the "backbone" of the system, based on my past experience.

upstatemike said:

One thing that would be a game changer for me would be if Elk allowed keypads to act as remote thermostat controls rather than just let you pick a pre-defined set point. The keypads have up/down buttons and a display so everything is there to implement a remote thermostat control.
 
As it is neither Elk nor ISY provide a solid native thermostat solution so you really have to have something like Homeseer or Stargate involved... especially if you need thermostat actions to trigger other events or speak or text changes in real time. Glad some folks are pleased with the Nest thermostat but I just haven't been happy with the reliance on Internet connectivity. It always seems to be offline when I need it the most.

Click to expand...

 
What is it that you would want your KP to be able to do other than to adjust a set point?
 
What thermostat actions would you want to see integrated?

Just to chime in, I would want a keypad stat to adjust set points and track/communicate so that I could track "on time" by stage, and control/ adjust humidity as well as heat.

All I need to do at a keypad is to see the temp and set point for each thermostat and to adjust them up or down manually (not based on pre-defined set points.) I haven't installed any touchscreen keypads yet so I would be pleasantly surprised if they include this feature which is not possible on my KP2s. 

upstatemike said:

All I need to do at a keypad is to see the temp and set point for each thermostat and to adjust them up or down manually (not based on pre-defined set points.) I haven't installed any touchscreen keypads yet so I would be pleasantly surprised if they include this feature which is not possible on my KP2s. 

Click to expand...

 
I haven't done an install with the KPNAVs AND controllable tstats yet, but I'm 99% sure that's the standard feature set...