Linux or Online heat loss calcs?

Gooserider

Speaking very roughly, the basement is an L shape with the long part being 20 x 35 with a 10 x 15 room hanging off one side. I'm guessing 8" thick poured concrete walls, and all but the 10 x 15 room (which has bare walls) have 2x4 furring and fiberglass insulation, covered by 3/4" wood board paneling.

This is why I think the basement number is off, the SF software has wall factor choices for a concrete wall basement, but no options for concrete plus insulation.

It is about 4' above grade and 4' below. If it matters, the bottom 3-4" is below the water table during spring thaws - we have a sump pump that cycles a lot during the thaws, or after a really heavy 2-3 day rain, otherwise not at all. The basement has 4 windows each about 18" x 32", double pane, and I've blocked 3 of them w/ 2" foam board. There is also a bulkhead exit door, so I have a total of about 42 sqft of door and window area in the basement

I've been using 0*F as my outside design temp, my town isn't listed, the nearest cities vary between 0 and 10 so I went conservative figuring I wouldn't have any "heat island" effects.

Gooserider

Gooserider

Linux or online Heat-loss calculators

First post here, I was sent by the folks over in the Hearth.Com "boiler room" forum. I would like to see what can be done to improve the efficiency of our house, and have been told that the first thing I ought to do is get a heat loss calculator to figure out the heat budget for the house. This would tell me what I needed for heat, and let me play with different options to see how they would work in terms of performance expectations and payback, etc.

However, we run this house ONLY on Linux - I do not have, and will not allow, any Microsoft O/S on our network, but we have several x86 based Linux boxes (mostly on Gentoo). The Slant-Fin program looks great, but it is only for Microsoft, and I have not been able to find any references to Linux based heat loss calculators doing a couple of searches here.

Can anyone point me to a Linux compatible Heat Loss calculator? If that isn't possible, how about one that does it online so that I don't have to worry about the O/S?

Thanks,
Gooserider

jp_2

well

paper and pencil always works......

ed wallace

linux based heat loss

well goose i gues your goose is cooked sorry bad pun think you need to find a compter that runs micro soft or get out the pen and paper

Ed Lentz_2

While I thoroughly sympathize with you goose. I am also against using M$ products, my line of work and the type of software I need to do my job excludes a Linux OS. That is also the case here as well. The trades here needed an easy to use system and the M$ OS provided that. They need to not have to tweak their PC OS to make things work. Granted that the Linux desktop has come a LONG way in the last year or so. But, I think that in this set of trades it won't take over.

I wish you luck.!

Gooserider

OK, so far, while I appreciate the responses, it sounds like nobody has any good suggestions for existing programs.

I have never done much of anything like this, Is a heat loss calculator something that can be done in a spreadsheet? If so, is there anyone that can point me towards source formulas and so forth for such a sheet? I know that Open Office can open a lot of Microsoft format sheets, but more importantly would be to have access to the formulas so that I can possibly translate them as needed?

Thanks,
Gooserider

Tom S._2

WINE for Linux

While no Linux expert, I've recently started playing with Ubuntu Linux and found that the WINE windows emulator/libraries can run some windows programs within the Linux graphical environment (I'm using Gnome).

Take a look here: Link to WINE for Gentoo

Something to try anyway.

Tom

albandjann1725849

try these

One by hand:

http://www.eminnetonka.com/community_development/permits/documents/heat_loss_calculation.PDF

One by web:

http://www.crownboiler.com/educate/heatloss.asp

You could program up the stuff in the by-hand method in Open Office. That's what the slantfin-ware does, more or less. Of course, by the time you get done doing that, you could also have done it by hand, but where's the reward in that? (Spoken as a proud, propeller-beanie-wearing member of the unix geek community for over 20 years.)

Brad White

Honk

Spreadsheets are a great way to calculate heat losses, Gander-man!

Write to me off line and I can set you up with an Excel spreadsheet. Of course you have to know the fundamentals. I have an essay I wrote which may help you also.

Brad

Gooserider

Well it looks like the simplest thing to try right now is to see if I can make the Slant-Fin program work under WINE, which I'll be trying shortly. I am currently bringing my Gentoo install up to the latest revision, and will be installing WINE as soon as that finishes. If it works I'm golden, if not, looks like the GF and I will be working on creating a spreadsheet that will do the job.

Gooserider

ed wallace

linux heat loss

how about sending the info to someone who has a heatloss program and having them run it

Gooserider

That isn't a bad idea, but I think I'd be better off if I could do it myself... A few reasons -

1. Without the program I'm not sure I'd be able to supply all the needed info, with it I can be sure I don't miss anything.

2. A large part of what I want to do is "situation modeling" where I get a layout of the house the way it is right now, and then play with different possible changes, such as adding insulation, repacing doors & windows, etc. and see how that changes things. This would let me see what sort of return on my investment I would get, payback periods, stuff along that line. I think I would wear out a persons patience quickly doing that, while I can do it as many times as I need on my own.

Gooserider

ed wallace

heat loss

do you have any friends thar have laptops that run on windows that you could borrow

Steamhead (in transit)

Got the Slant/Fin calc program 2.0 to load in WINE under Ubuntu

had to jump thru a few hoops though, took me a while since I'm not a Linux expert:

1. Configure WINE to emulate Windows 98 (S/F program works under regular Win98);

2. Create a folder "slantfin" in the root folder of the WINE virtual C: drive;

3. Insert the CD (or select the downloaded files, unzip if needed), copy its contents to the slantfin folder you created;

4. Start the installer from Terminal- type the following: wine c:\slantfin\setup.exe


NOTE- the double backslashes are not a typo!

The installer runs, creates a "heatlossexplorer2" folder in the slantfin folder, and WINE places an icon on the Desktop.

I then copied the C:slantfinheatlossexplorer2datajobs folder from my Windows XP Pro machine to my Ubuntu machine, and all the jobs therein displayed on the Ubuntu machine. I haven't tried to print from the Ubuntu machine, no printer is set up on it yet.

OK, time for bed. Let us know how it works for you!

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

Gooserider

Good News / Bad News...

First, the good news... I finally got WINE installed on my Gentoo box, and after a bit of fiddling, I was able to get the Slant Fin software to install and run on my system.

The not so good news is that the software, which does seem like an excellent program overall, is essentially written for a "normal" house design. Our house is a "contemporary" style, and I'm not sure how to modify my numbers to make it work with some of our strange features...

The house is a sort of "A-frame" style with a 12/12 pitch roof, on the first floor, it has a cathedral ceiling living room, then a kitchen/dining area, then a row with two bedrooms and a bath - centered over the latter two sections is the master suite on the second floor.

In each of the 1st floor bedrooms, part of the ceiling is under the 2nd floor, part is under an attic space. How do you figure a ceiling factor?

In the living room, the ceiling ranges from about 12' along the side walls to 24' in the center, with a 12/12 pitch on the inside of the rafters - What do I use for Height in the room? How does this impact the ceiling factor, and does it matter that the ceiling area is obviously going to be much greater than the floor? For added fun, one wall is about 1/2 exposed (screen porch) and 1/2 cold partition into an attic space - how do I figure that?

In the master suite, some of the walls are also partially cold partitions, and partially on an angle with the roof.

Last, (I think) the basement is about 4' exposed, above ground concrete, and 4' below grade, how is that handled?

Thanks,
Gooserider

Chas_5

Handling

You handle it with care. I have a couple of similar rooms, Cathedral ceilings slab on grade, unconditioned space and 1/2 concrete etc. Treat them as seperate rooms with heated space above. With heated space adjoining or above you get zero heat loss.

Big PIA

Much danger.

Steamhead (in transit)

I generally average the height of sloped ceilings

never had a problem.

Regarding the basement wall, under Exposed Wall Factor, the Concrete Block and Poured Concrete options include walls that are partially above and below grade.

For the exposed/cold partition wall, simply enter the length and factor for each.

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

Gooserider

OK, I think I have everything done... I created a bunch of "phantom rooms" to break up the irregular rooms into more uniform shapes. For instance I have the living room divided into a "low" and a "high" room, with the low room height = the level of the 2nd floor, and the high room height the average of the remainder, and giving a "0" factor for the dividing line.

I came up with 87K BTU/H total, w/ about 39K for the basement, 37K on 1st floor, and 8K on the second. Obviously you folks don't have my measurements, but does this sound like about the right order of magnitude? The house is a "contemporary, about a 36x36 footprint, with a 12/12 roof limiting the size of the second floor, and about 30 years old, poured concrete basement about 50% below grade, 2x4 construction, w/ fiberglass insulation.

One area where I'm pretty sure I don't have the right wall factor is the basement - The Slant Fin program's "concrete wall" options only offer a value for plain concrete part above and part below grade, which is fine, but I don't seem to get any credit for the fact that many of the walls are covered w/ 2x studs, fiberglass, and wood board paneling - I know there is supposed to be some advantage to insulating those walls, so what should I be using for a factor?

Thanks,
Gooserider

Steamhead (in transit)

That's probably close enough

to get you to the point where you can start looking at boilers. Since you have insulation that the calc doesn't allow for, maybe look for a net rating of 85 MBH rather than 87?

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

tim smith

Basement sounds high

What are the dimensions of basement and how much is above and below grade as far as walls go. Also how much glass and new double or old single paine. What is your outdoor design temp where you live? If I make an assumption of 24 degree outside design temp, basement 1000sft, 8ft ceilings, no insulation anywhere, 100 sft glass single payne, slab on grade. The basement would only be appx 23,000 btu and thats a poor envelope, no insulation. That's why basement seems high. If 10 degree design it would be 30,000 for basement. all appx, done off memory.

tim smith

Regarding basement

I don't see your basement over 20,000 btu at 0 degree, that's significant change from what you calculated.

Gooserider

I found the reference I was thinking of for the idea that adding insulation to the basement walls makes a BIG difference - http://www.woodstove.com/pages/basement_install.html - In essence they say that an 8" poured concrete wall has an R-value of 0.064, and w/ 2' above grade, a 20 x 30 basement will loose about 43,750 BTU/hr @ 20*F and 56,250 @ 0*. However adding 3.5" fiberglass, w/ studs and sheetrock will reduce that to 2,334 or 3,000 BTU/hr respectively, so it certainly does sound like my current number for the basement is way off.

Presumably the correct fix for this would be to adjust the "wall factor" - but I'm not sure how Slant-Fin is determining this. For above grade, stud walls, 1/total R-value for the wall seems to work, but this doesn't seem to work for the basement walls factor value.

However I've just tried a bit of assumption work, and got a value of 25.6k BTUh - I took 1/.036 (the SF wall factor) to get an R-value, added for the insulation, and came up with R-15.8 for the insulated walls. 1/15.8 gave me a "wall factor of 0.063. In order to save time, I glommed all the insulated and un-insulated wall areas into two rooms with the same total exposed wall areas, and distributed the door and windows appopriately - came up with an insulated room 30.8' x 30.8' drawing 13,500 BTUh and an un-insulated room 30.8' x 8.9' drawing 12,100 BTUh for a total of 25,630 BTUh, which I think might be closer...

As an additional point of data, the house currently has a 93% Tappan HVAC unit, FG6RC-120C-20C, which appears to be a 120K BTU in, 110K BTU out - It heats the house well but we try to avoid using it (I hate the sound of money burning), and have been heating the upstairs about 90% with a VC Encore Cat wood stove (8,700-41,700 claimed BTUhr output range) which is barely adequate for the 1st and 2nd floors, but doesn't do a thing for the basement.

Gooserider

tim smith

you are reading too much into this

your #s are off. redo. Tim