The mothership

hr

on Siggys HDS program. It lets you play with foam R value depth of insulation, etc.

I'd second the opinions on humidity control, especially for an indoor pool! Sounds like the pool could heat the whole building.

hot rod

<A HREF="http://www.heatinghelp.com/getListed.cfm?id=144&Step=30">To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"</A>

singh

Hobbit House

I've just been given some prints on an earth sheltered home to be built next spring.
3500 sq. ft, not including enclosed pool room. All concrete, with passive solar orientation. Three sides and roof will be covered in dirt.
I am to size and design the heating,air and dhw. Using geo and solar collectors, no boiler backup. All radiant, in slab ,plus heat the pool.
I'm told R54 in walls. Alaskan slab for floor, about R24?
I'm looking for any good source or books on earth shelter structures, and some real numbers relating to the HVAC side.
Did I mention the grey water system for plumbing.

Also, I forsee a lot of design time, can someone email me on what I should be
charging for this, should come spring and he takes my info and shops elsewhere. Thanks.

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

ScottMP

Singh

I don't have answers for you, but it sounds like a really cool project. I am sure you'll do fine.

I would build some of your design time into the bid and charge for the rest. Let them know to do this correctly you need to spend alot more time than normally and must charge for your design time.

Scott

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Brad White_88

Singh- I agree with Scott

You must charge for your design time. E-mail me off line and I will give you an idea of what you might charge or how you might structure the proposal.

It does sound like a very cool project! One aspect I see as taking some design time is modeling the time factor into heat loss and gain.

When you say "pool room" are we talking Minnesota Fats or Mark Spitz? I have swimming pool design experience and could help you there. If 8-ball, well, scratch that

Brad

Gene_2

DO NOT

give any plans or designs to said person unless you have a signed contract. If they went to any engineering firm you can bet they would not get anything till the check book came out. Your time is very valuable (and all of your education).

P.S. If you need a hand, Mark loves working with grey water and sewage.

Darin

singh

Brad and Scott

Thanks for the vote of confidence.

Brad , I will email you.

One point I'm stuck on is what the constant or average soil temps may be, and what might be the real R values for the walls. Or since it's high mass, it may be a moot point, once the structure is charged with heat. (that should take a week or so)

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

singh

I was going to give Rick a buzz.
He's an expert on all things sewer related.

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

jp_2

soil temps, estimate guess

well, I think you could make some good guesses.

if you know the frost line depth, footing depth, and you know the seasonal lows. I would make a graph from surface temp(low seasonal temp) to footing depth, calling footing depth temp 35-40F since you do not want footing to heave.

then draw the sloped line between the two points, you can extrapolate to other depths.

going one step further, find out when the weight restrictions are off on roads and that will give you an idea as to the 'shift' in ground temp during the season.

takes most of the winter to cool the ground, then most of the summer to warm it back up.

JimGPE_23

Moisture

Spend a significant amout of time considering where the room humidity is going to condense out. The ground is in the 50's, and there are going to be times when 50F is below the dewpoint of the air in the home, e.g. in the summer if they leave the windows open. Consider where the 50F surface will be and whether you have a vapor barrier on the warm side of that point.

My sister and brother-in-law owned one of these homes, and they spent all their heating and cooling energy savings, the major selling point of such a home, running dehumidifiers, and they still had mold and mildew problems.

If there really is a swimming pool in the structure, that will REALLY make for a challanging moisture situation.

With the home earth-sheltered, there isn't much call for cooling, the call being based on a drybulb sensor. No cooling = no dehumidification. Forcing the cooling to come on drives the temperature down (making m'lady cold) and the relative humidity UP, and that exacerbates the problem.

Yeah, moisture considerations should be given a LOT of thinking.

My $0.02.

Weezbo

that must be the ticket.

we have been churning the same idea about and this summer we are off to Doit the whole is cut,i am currently looking into the purchase of large plastic pipe for the underground solar "collector". close to 2000 cubic yards of dirt.

yesterday i had no luck in aquiring the pipe from a 93 year young alaskan who makes it his business to know where every piece of auctionable anything is located:)

the miners around here must have bought all the stuff we salvaged 20 years back for the water intensive operations involved in getting the gold out. the farmers seemed to have bought up alot of the salvaged pipe. PVC is abundant where you live here we use alot of ABS..new material may prove somewhat spendy...

Brad White_9

Mark loves working with gray water and....

sewage? You may need to clarify that is true only when it is inside piping, Darin. I hope.

singh

Jim

Thanks for the info on moisture.
My finished basement is the same way, feels cool all year,(eventhough tstat set at 74*) no need for a/c
and we usually heat until June, and run the de-humidifier up to Oct.

Yes, there really is going to be an enclosed pool. At first I said great, all the heat you would normally dump into ground loops can heat pool, and in winter pull from pool to GSHP's.

This building is 150' long by 30' incl. pool room.
It will end up looking like an aircraft wing sticking out of the ground.

I also thought about the slinky loops running 80' along side of wall and if they may have any effect on the total r value being that they will be pulling heat or dumping near by.

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Mad Dog_2

Dream project...................................................

But make sure you get paid all the way thru, Singh. Also, keep in mind , if you do get it.....it WILL take up most of your time...researching....installing...tweaking. I'll email you what I would charge. Good luck. Mad Dog

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

S Ebels

This is where

This is where the line between contractor, designer and engineer becomes very blurred. Sounds like you'll have to wear all three hats on this one.

To paraphrase Abraham Lincoln........" An engineers time is his stock and trade"

That's why you have to charge for it.


I have to admit, I struggle with these types of questions too. Some of the projects get so involved that I can have 30-40 hours of head scratching before I'm able to estimate a price. Customers seldom realize this and often raise a bloody fit when I tell them there is a flat fee for this whether they hire us to do the work or not.

If they do, I tell them to hire an engineer or a mechanical designer to come up with the layout. Sometimes this calms them down but usually I get the standard " Joe Blow doesn't charge a thing, wht's up with you"?

On more than one occasion, I have had the satisfaction of getting called out to the job after the fact when "Joe's" system turns out to be worth exactly what they paid for the design. In a structure like you're dealing with there, a "fix" would be nearly impossible.

What goes around, comes around.