Pennsyltucky, Have you looked at Speedfloor (http://www.speedfloorusa.com/)? I know someone who had this put in a few months ago and he is very happy so far.

You could get a couple water beds... just don't plug in the electric heaters. ;)
A large fish tank...
Don't have any empty rooms. Think of a fridge or freezer, when it is full, the unit doesn't have to work as hard to maintain the temp.

You can get help from a reputed basement design company that have more experienced and can build your thermal basement as your thoughts with their ideas.


Virginia Basement

Wow, where do I start?

Thermal mass evens out temperature fluctuations. The more internal thermal mass in a house the better it will perform period. That said you have to understand how it works. One, as the thermal mass in the home increases the thermal lag of the house gets longer and longer. This means you do not change the temperature of the inside of a high mass home at a whim. High mass homes perform differently than a standard house. An example is that setback thermometers, air temperature thermometers do not work without a computer that understands the thermal lag of the home.

Passive solar homes require thermal mass to function. If a home is going to absorb thermal energy and not overheat large mass is required. The required amount of mass is about 22 cubic feet of high capacity thermal mass per square foot of southern glass. Most homes are under massed in design due to a lack of understanding and use of dynamic thermal modeling. Poorly designed solar homes overheat or underperform. Properly designed and executed homes passively self-heat and cool without the need for a standard HVAC system.

Light materials like wood, fabrics, drywall and insulation provide almost no functional thermal mass. Thermal mass needs to have a high thermal capacity and a conductivity adequate to load the material at the max absorption rate of the house as a system. This typically limits the functional thermal mass materials to stone, concrete, hard surfaces, compacted soils, modified soils, metals, water, and other dense materials.

Small amounts of thermal mass such as 1.5 to 4 inch concrete slabs evenly distribute the heat from a heating system. Such slabs have a one to 6 hour heat lag. They are only capable of small amounts of solar absorption. Increasing to a 12 inch slab will increase the thermal lag to 12 to 24 hours. This amount of thermal mass provides for dihedral averaging in most climates. This amount of mass typically allows for maintaining an average temperature day to night. This eliminates peak static case heating and or cooling. Let’s say the max temperature in a given day is 70 and the night time minimum is 40 for a daily average of 55. The HVAC system will only have to handle a 10 degree delta T to keep up because of the thermal mass averaging. A non-thermal mass standard home would have to have a HVAC system that can handle the Max delta T of 25. This case would require a HVAC 2.5 times as large.

Increasing the insulation levels and air tightness of the house reducing the max thermal need of the home by halve would both halve the HVAC system size and double the heat lag in the thermal mass. Continuing this progression of better insulation, windows, doors, HRV, air tightness, solar gain windows, microclimate and thermal massing will eventually lead to an elimination of the need for a standard HVAC system. Optimizing and integrating all these variables allows for the highest performance home for the lowest cost. This is what an engineer, designer or architect is supposed to do. Few are capable of this task.

Integrating this process with local sourcing, alternative materials and methods, low embodied energy materials, low maintenance materials, live walls or roofs is what I call the H.I.D.E.N Systems approach. That stands for Holistic Integrated Design using Engineered Natural Systems. This is how I design, engineer and optimize, self-heated and cooled, green, sustainable, carbon neutral, net zero energy homes at the same cost as a standard custom home of the same quality in the area. These homes have no utilities. This saves the average home owner $100,000s over the life of the home. If you buy a standard home you are reducing the quality of your family’s lives because of the lower comfort of the home and the reduction of financial resources you are acquiescing too.

Expect properly designed homes and buildings. Don’t handicap your life. If you cannot find a local individual to deliver this level of home value, contact me and we will help you with your project.

http://www.zehtalk.com/

Brian

http://solar-components.com/tubes.htm

http://www.builditsolar.com/Project...lIntro.pdf

https://www.thenaturalhome.com/heatstorage.htm

These are kinda cool.

https://www.thenaturalhome.com/waterTubeBlue2.jpg

Brian,

Am I mis-reading your recommendation of 22 CUBIC feet of per square foot of south glass?
A good guideline in my climate (Colorado Front Range) is south glass should be 8-12% of the floor area (let's say 10%).

So a thousand sq ft home with 100 sq ft of south glass should have 2,200 CUBIC feet of mass?
Assuming all the mass is in the floor, you are recommending a slab of over 2' thick.
If the slab is 4' (333 cubic ft) you are suggesting 15 sq ft of south glass.
If I added a 40' long by 8 feet tall 6' CMU wall to the inside would only gain 7 sq ft of south glass.

Most articles I have read suggest that any thermal mass over 4-6 inchs from exposure is wasted
and would even become a heat sink.

If you want to average the energy over a year’s input that is what is required. Use triple pane windows and you can cut that in half. This assumes that you do not want the house to overheat during absorption of energy. It will keep your house comfortable. You want an internal heat sink to absorb the energy. I am a proponent of high mass walls. They allow for an easy place to have the mass. Note that it is climate dependent, for example in Hawaii it is 1/3 of that amount. In Alaska it is double that amount. You can also compensate with higher insolation values etc. It is an integration of the entire system. These values also allow you to have a home that is passively heated and cooled. The mass does not habe to be concrete. It can be earthen mass under the floor, It can be in a water tank in the envelope or another embodiment. Call me if you want to chat about it and I will be happy to explain how it all works. You can find me through my web site at http://www.zehtalk.com/#About

Brian

Brian,

I understand how thermal mass works and am a big proponent of moderate mass, pasive solar low energy homes.
I questioned the 22 cubic foot of mass per sq ft of south glass as unreasonable and your answer is that you are trying to store
a "year's input". A different topic than what was being discussed and one that I have little interest in. I'm more interested in
practical, proven, cost effective solutions. I've seen the math, you couldn't possible "passively" heat 22 cubic feet of mass with 1 sq ft of
south glass.

High thermal mass dynamic annualized calculations and modeling are not a simple math problem as you indicate. It takes a couple days of engineering analysis to work out the models and the finite elemental analysis involved. I am an engineer and have been designing and building high mass homes for over 30 years. I can accurately model the performance of homes in a given climate. I also have the data showing that the numbers are confirming real world homes.

Comfort comes from temperature, humidity and air flow control. High internal thermal mass provides temperature and some humidity stabilization. A high thermal mass home is capable of being exposed to extreme weather for weeks without a dramatic effect on the internal temperature. Once the extreme weather passes the home can recover at a similar rate. The internal temperature never falls outside of a comfortable range. The more mass the less the temperature will change.

The mass stabilized to the average design temperature and will float above and below that temperature during the year. Annualized homes will be 6 months out of phase with the seasons due to thermal lag. That means they will be warmest in the winter and coolest in the summer. Given a designed temperature of 73 degrees and a float of +- 3 the home would be 70 during the hot summer and 76 during the dead of winter with no additional thermal input.

Accomplishing this requires micro climate, site, and design assessments. The entire system design has to be integrated in the process. The mass is at the internal temperature to start with. The daily thermal inputs only change the mass temperature a very small amount. One of the goals is to have enough mass that no single weather event can overwhelm the mass. High mass homes well designed work though most people are clueless of how they work and how to engineer, design and build them.

If you have additional questions I would be happy to talk to you. You can find me through my website http://www.zehtalk.com/.

Brian

Posted By rpatterman on 09 Feb 2012 09:26 PM
Brian,

I understand how thermal mass works and am a big proponent of moderate mass, pasive solar low energy homes.
I questioned the 22 cubic foot of mass per sq ft of south glass as unreasonable and your answer is that you are trying to store
a "year's input". A different topic than what was being discussed and one that I have little interest in. I'm more interested in
practical, proven, cost effective solutions. I've seen the math, you couldn't possible "passively" heat 22 cubic feet of mass with 1 sq ft of
south glass.

Sure you could, you're just integrating the solar gain over a much bigger time period than one day, is all. You're just not "heating" it to anything above a comfortable room temp.  In more customary passive solar designs the thermal mass to glass area is much lower, and the daily swings in temperature is much higher.

I'm not advocating this as any sort of practical solution though, and the notion that one can do annual averaging with only that much water and get a fully passive house out of it needs the whole model of the house and occupancy, etc, but without high-R it's not going to do much. A 100 square feet of glass at 22cubic feet per square would need a 13' cube of water as mass storage, and yes, that is a VERY substantial thermal mass compared to that any standard-construction house (about 68 tons of water!).

Dana,

The 22 feet is if the mass is earth. If it is another material the volume is obviously different. The R-values regulate the total amount of mass needed. R-2 requires 22 feet of mass. R-100 requires 1/2 foot of mass. You have to build a model and then let the computer adjust the R-values and the mass values for the house to get to the least expensive incarnation of the envelope for a given climate.

Brian

William,

I am more than happy to share. Here is a wall crossection and some High Mass homes I am working on.


This is a wall section though not totally detailed.
 
This is a 1450 square foot, 2 bedroom cabin which is self-heated and off grid.

This is a 7000 square foor Caribean retreat, which is self cooled and dehumidified



Brian