Sizing natural gas line

[enrare]

I live in Denver area at about 5400 ft elevation. I need to run a natural gas line branch into the attatched garage for a 60,000 BTU heater. I've been looking at the charts for gas pipe capacities to determine what size line I need to run, but don't know if elevation will affect what size pipe I need. Also does the number of 90 deg fittings have any bearing on flow and pipe size. I will have 6 turns in the new run of pipe.

Some more info to help: There's about 36 ft of 3/4" black pipe from the meter to my water heater and furnace location. I have Tee'd into the line at that location and it will require about 30 ft to reach the heater location. So my question is would 1/2" line be adequate or should I use 3/4" line due to the over-all length of run from my meter to the garage heater. Maybe more importantly is my recently realized concern if a 3/4" main supply line will support a 70,000 BTU furnace, 40,000 BTU water heater and now add the 60,000 BTU garage heater for these distance of pipe runs. Again I don't know how my elevation affects these numbers/calculations.

 

[Tim The Tool Man]

Personally I would go with that yellow stainless GasTite tubing and avoid all the elbows. Go with the 3/4 diameter. Unfortunately you would need to be trained/certified to be able to purchase and install the stuff. You might want to bite the bullet and hire an HVAC tech to size and run the line for you. Were I closer I'd offer to assist...

 

[nwav8tor]

Unfortunately, I don't have the time to run the calculations, but there are gas supply capacity tables available on the internet. I'd guess that 3/4" supply for those three appliances and the distances involved would be too small. And, yes, the number of fittings (tees, ells, 45s, etc) will all effect the calculations (usually accounted for by increasing the lenght of the run).

Paul

 

[enrare]

Personally I would go with that yellow stainless GasTite tubing and avoid all the elbows. Go with the 3/4 diameter. Unfortunately you would need to be trained/certified to be able to purchase and install the stuff. You might want to bite the bullet and hire an HVAC tech to size and run the line for you. Were I closer I'd offer to assist...

Thanks for the offer. I guess my main concern right now is if the 3/4" line I have coming into the house is capable of supporting the load when all 3 appliances are running (which is very realistic). If it's not then I fear my dream of affordable heat in the garage is dead. I guess when they built this house 20+ years ago they never took future expansion into account and used min size line to save a few $$

 

[rlitman]

I have a 210kBTU boiler, and the line going into it is only 3/4" (off the top of my head). Granted, that line is only about 4' long, and it branches from a 1 1/4" pipe.

I'm pretty sure that if you have high pressure gas coming from the street with a regulator next to your meter, you've got plenty of gas supply to do whatever you want, so there is no need to give up on your dream.

Worst case scenario (AFTER doing the calculations), you either up the size of the line running from your meter to your water heater, or you tee off of the line close to the meter, to go to the garage heater.

And that's pretty much what I'm thinking, after looking at this:
http://www.engineeringtoolbox.com/natural-gas-pipe-sizing-d_826.html

36' of 3/4" pipe (x1.5 to factor for fittings) = 54', which would deliver a little over 100MBH. That's just barely enough for your current load.

You could probably replace the existing run with 1" (or even 1 1/4"), and then run 3/4" from there to the new heater.
Or you could put in a new 3/4" run that tees off from near the meter.

 

[FJ 432]

I had them come to my house on a possible fireplace insert with a ****** off for future use on my garage heater. Knowledgeable folks and the quote was free.


http://www.thegasconnection.com/

 

[HoosierBuddy]

I ran it through GASCalc:

30 feet of 1/2" pipe at 60,000 BTU/Hr at 5400-feet elevation...Pressure drop = 0.25-inches w/c.

So...that would be fine.

I would most definitely use black iron (aka maleable iron, aka black steel) pipe instead of the CSST the other poster suggested for a ton of reasons, including durability and ease of compliance to code (CSST requires a few things to make it code compliant.)

Ohh...and 36-feet of 3/4" steel pipe will carry 250,177 BTU/hour at 1" pressure drop...which also should not be a problem....unless your total connected load that will all run at the same time is more than that.

Phil

 

[rlitman]

Agreed. If it is staying inside, black pipe all the way.
I do not have GASCalc. My numbers were way on the conservative side based on conservative tables, but yours seem a little optimistic. Each elbow adds about the same pressure drop as 2' of pipe in a 3/4" natural gas system:
http://www2.iccsafe.org/states/Seattle/seattle_fuelgas/PDFs_fuelgas/Appendix A.pdf

If you're going to try to cut it that close, get a better estimate on the actual length. I'm not saying it won't work (it probably will), but you're close enough to the boundary condition that refining your estimate is a good idea.

 

[enrare]

First I'd like to thank everyone for the help. I will add some more details since the situation looks borderline. I have 3/4" line coming to the meter, there is a diapgram type looking regulator before line enters meter. By looks of my meter all the connections are for 3/4" line. Gas line from meter to where I have tee'd off for the garage branch is 37 feet and there is (5) 90 elbows to that point. From that tee there is two more 90 and 4 ft of 3/4" pipe to another Tee for furnace and water heater. I have 12-14" of 1/2" pipe from tee into furnace. From furnace tee to water heater is 2 ft of 3/4" pipe and then 24" of pipe into water heater. From where the garage line branches off the main line I will need 29 ft of pipe then a short piece of flex line to make the connection to the heater. The garage line will need (7) 90 elbows unfortunately. I could use some 45 elbows to eliminate 1 or 2 of the 90's if that helps
My furnace is actually 75,000 BTU and not the 70,000 I originally posted. My Hot Dawg heater has a 60,000 BTU input and 48,000 BTU output if this helps calculations. I can not find any input/output ratings for the furnace and water heater. Again this is at 5400 ft elevation.

 

[Steevo]

I had a very similar situation when I plumbed my shop.
The house had a 1" gas line coming in from the meter, with a couple of el's, and then it Teed at about 18' in from the meter. From the Tee, it was 3/4" to the kitchen for the stove, and 3/4" all the way to the far end of the house, which was about 35 feet or so, where it teed again, feeding the water heater and forced air furnace.
The plumber I was using determined that we couldn't add the 75k BTU MrHeater run to the end of that without having supply issues if/when too many gas appliances were run concurrently.
I ended up with a T at the meter, and an all new 1" yellow poly underground run around the house and out to my shop, with nothing but the unit heater on it, using 3/4" black pipe.

 

[enrare]

From what I'm hearing an option is to put a tee near the meter and run a dedicated line to the garage heater instead of tapping into the current line feeding my furnace and water heater. Couple of questions. Is this Tee being placed on the inside of my house right where service enters from meter or is the Tee placed outside at the meter where the gas company and city will be able to see my "handy work". Will I still not be "bottle necked" and limited on gas flow since the meter only has a 3/4" pipe on the outlet side??

 

[rasit]

The tee would go before the meter (on the high pressure side) and would require another regulator to decrease the pressure before entering the garage. This would eliminate any bottleneck. Check out the following link for a good sizing program:

http://www.wardflex.com/sizing.htm

Version 2.2.4 unless you use Autocad...

 

[zmaxmotorsports]

A picture of current set up would help,Id say the 3/4" is too small to run everything if youre running low pressure gas

 

[rlitman]

The tee would go before the meter (on the high pressure side) and would require another regulator to decrease the pressure before entering the garage. This would eliminate any bottleneck.

Good god no. That's totally unnecessary, and a great expense. Plus there would then be a new recurring expense of a second meter (if the utility even allowed that, which is doubtful if you don't have a second residence).

In any case, your current regulator should have the capacity to run every deep fryer in a McDonalds. Your meter is -probably- sufficient to run whatever you need. By me, the smallest meter the utility will install, is capable of handling 175MBH. That meter still ran my 210MBH boiler just fine (as the person from my gas company expected), but in an abundance of caution, they upgraded my meter to the next size up, to be sure it would accommodate my dryer, range and BBQ grill at the same time.

You can absolutely tee off right AFTER the meter. Don't worry about the size of the pipe going through the meter. Worry about the size of the pipe going the full distance to your heater.

 

[HoosierBuddy]

The tee would go before the meter (on the high pressure side) and would require another regulator to decrease the pressure before entering the garage. This would eliminate any bottleneck. Check out the following link for a good sizing program:

http://www.wardflex.com/sizing.htm

Version 2.2.4 unless you use Autocad...

Bypass the meter?

Felony.

Phil

 

[rasit]

The tee would go before the meter (on the high pressure side) and would require another regulator to decrease the pressure before entering the garage. This would eliminate any bottleneck. Check out the following link for a good sizing program:

http://www.wardflex.com/sizing.htm

Whoops... I need to pay more attention when posting at 6:00am. I didn't realize the OP was talking natural gas. As others have pointed out this is absolutly the wrong way to go however it works for propane. I had a similar situation and it ended up cheaper to:
Shut valve off at tank, tee into the line before the regulator (high pressure side), run 125' of new 1/2" plastic underground line to the garage, add additional regulator and valve at garage, stubbed into garage (low pressure side), pressure test from the tank to the stub, turn valve back on at the tank, purge the line. Total cost of material was $90. Sorry for any confusion, hope nobody killed themselves......

 

[BadgerBoilerMN]

No gas line can be hooked up before the meter. You should get some licensed, professional help before someone gets hurt.

This is not something you guess about or write a letter to Dr. Abbey. Seriously.

 

[CNGsaves]

First I'd like to thank everyone for the help. I will add some more details since the situation looks borderline. I have 3/4" line coming to the meter, there is a diapgram type looking regulator before line enters meter. By looks of my meter all the connections are for 3/4" line. Gas line from meter to where I have tee'd off for the garage branch is 37 feet and there is (5) 90 elbows to that point. From that tee there is two more 90 and 4 ft of 3/4" pipe to another Tee for furnace and water heater. I have 12-14" of 1/2" pipe from tee into furnace. From furnace tee to water heater is 2 ft of 3/4" pipe and then 24" of pipe into water heater. From where the garage line branches off the main line I will need 29 ft of pipe then a short piece of flex line to make the connection to the heater. The garage line will need (7) 90 elbows unfortunately. I could use some 45 elbows to eliminate 1 or 2 of the 90's if that helps
My furnace is actually 75,000 BTU and not the 70,000 I originally posted. My Hot Dawg heater has a 60,000 BTU input and 48,000 BTU output if this helps calculations. I can not find any input/output ratings for the furnace and water heater. Again this is at 5400 ft elevation.

First, you've need to know that gas line BEFORE the meter is totally irrelevant. The GasCo is responsible for that portion and likely has high pressure that would satisfy commercial business. The REGULATOR that is right before the meter is what controls the NG pressure that ultimately gets through to your residential house. Typical residential pressure is 7 to 8 " water column, which is equivalent to approx 1/2 psi.

What could be problem for you is black pipe size, and length, AFTER the meter to your furnace which you say is 3/4" black pipe. You may risk not having enough flow to both 70K Btu furnace and 60K Btu garage heater if all you have is a long 3/4" black pipe feeding everything.

Your best bet for having both the furnace and garage heater to have enough flow, is to put T for garage run as close to meter as possible.

Worst case, you'll have to UPSIZE the run from meter that goes to furnace to say 1 1/4" or 1 1/2" then you'd have plenty of flow to both furnace and garage heater. Or a work-a-round could be runing ********* pipe for that long run to garage heater so I would not recommend you trying just a 1/2" run over to garage heater. Personally, I would go with 3/4" black pipe all the way to garage heater.

 

[enrare]

Thought I'd give an update. Have been looking at having the heater installed or at least a gas line run to the heater location. First HVAC person I had out was a recommendation/referal from local Modine distributor. Took a few attempts to get a hold of this guy. He came out looked things over, never took any measurements and said he would have me an estimate in a few days. A week later had not heard back, so I placed 2 calls leaving voice mails...never have got a response. Second HVAC guy I called declined once he learned I had a used Hot Dawg to install due to "warranty and liability reasons". Asked if he could at least run a gas line, he declined and refered me to another place called The Gas Connection, Inc. (as previous poster suggested). The Gas Connection came out yesterday and gave an estimate for installing gas line. They charge $12/ft for black pipe or $16 for Trac Pipe. I have around 70 foot pipe run from meter to heater location. Their estimate $1179 + cost of permit for JUST the gas line seems a bit high. I can go to my local plumbing/HVAC supply and purchase 3/4" black pipe for $3/ft. I also ask how much for doing the venting, was quoted $295 to connect my short 3 foot horizontal vent run (to keep cost down I would hang heater and supply the vent material).

Not sure what I want to do. My city building dept said they don't care if I do the work or a licenced pro does it. They just require a permit be pulled and paid and on inspection everything needs to meet 2009 IRC and 2009 International fuel and gas codes, additionally all manufacture installation requirements for heater and venting must also be met.

Homeowners insurance agent says that as long as "local jurisdiction requirements are met" he dosn't THINK there would be an underwriting issue if I did the work myself and it passes city permit inspection, but recommended it be professionally installed

 

[ForceFed70]

Nothing wrong with a homeowner permit. So long as it passes inspection your insurance will cover any damage even if it comes down to something you did wrong.

For that price I'd do it myself. It's just a bunch of pipe and pipe fittings. The biggest challange is threading the pipe. Home Depot will cut to length and thread for you. Otherwise, you could rent or even buy your own threader and still come out well ahead.

 

[ebstein]

I just ran 50' of CSST to my garage heater, so I don't think you'll have a problem...and I just went to Menards and bought the tubing and fittings...no licenses required...

 

[CNGsaves]

+1 on doing it yourself with BLACK PIPE steel, with a helper based on lenghth of pipe you've got.

Watch CL or Ebay and buy yourself a Rigid 00-R threader that has inter-changeable dies. Here is example that comes with pipe cutter:
http://www.ebay.com/itm/RIGID-00R-P...pt=BI_Pipe_Threaders_Dies&hash=item257ab649f8

In Denver, you've got great wholesale supplier as follows:
Winnelson
2300 W 2nd Ave, Ste 1
Denver, CO 80223
(303)777-2300
where you can order contractor-length sticks of pipe (ie 21 ft long) that are pre-threaded and much cheaper than HomeDepot. Buy all your unions, elbows, collar, shutoffs, etc at Winnelson which likely will be less than HD.

Plan out your entire route and run 3/4" black pipe and buy some hangers (either specialty or "plumbers tape") to hold the pipe up. Have a shutoff at start of run and collar in spots where you might need to take apart run later. Add a shutoff at end near heater and be sure to plan on drip leg. Last couple feet to heater can be flexible steel.

Teflon tape all the male ends of pipes (or pipe dope, depending on local code/inspector preference) as they go together and test for leaks with soapy water on all joints before going live. Good luck and let us know how it turns out.

 

[rlitman]

OMG Nooooo. Teflon tape (even the yellow stuff) is an instant fail by any inspector for NG plumbing around here.

Pipe dope is the only appropriate material to use on male threads (Rectorseal 5 is my favorite).

 

[CNGsaves]

OMG Nooooo. Teflon tape (even the yellow stuff) is an instant fail by any inspector for NG plumbing around here.

Pipe dope is the only appropriate material to use on male threads (Rectorseal 5 is my favorite).

You might be right for NY. . . . ie depends on location . . . . inspectors or code might not like teflon tape in your neck of the woods.

Here in KS use of teflon tape is no problem for NG . . . assuming no leaks!

See EDIT above to cover code specific by location. However, both Colorado and Kansas allow either Teflon tape or pipe dope for sealing black pipe.

 

[BadgerBoilerMN]

Ya, nuttin to it. The guys at the Depot are experts at that junk. They work at Home Depot for low wages cause they're so sharp...

Worse case, you blow the house up. Get some help. Your questions disqualify you. There is the sizing of pipe and then there is the installation. Have a gas detector? Know what pressure the gas line will run? Know whether to use pipe tape or dope? How often to support the pipe you choose to use? What type of hanger?

Lets start with the garage heater...60,000? My 2100sf house uses 31,000 btuh in the coldest weather here in Minnesota.

 

[HoosierBuddy]

IIWY I'd do it myself, but I know what I'm doing and have the tools.

Is there any chance you have a friend or neighbor that is a plumber, HVAC guy, works for the gas company, etc?

A case of coors might go a long way.

Phil

 

[enrare]

IIWY I'd do it myself, but I know what I'm doing and have the tools.

Is there any chance you have a friend or neighbor that is a plumber, HVAC guy, works for the gas company, etc?

A case of coors might go a long way.

Phil

Unfortunately no. My brother-n-law is a supervisor for a large construction company. Thought he might be able to get me hooked-up but all the HVAC guys he deals with are on the commercial side of things and had no intrest in my small residential job.

Eventhough I have inquired to 3 different outfits, I have only recieved 1 actual estimate. I may try and get a few more estimates then go from there. Plus I need to dig a little deeper into my homeowners insurance coverage since my agent did not sound really sure how Kemper Insurance would handle a fire claim if due to work done by myself even if it passes a permit inspection.

 

[Jackfre]

You might be right for NY. . . . ie depends on location . . . . inspectors or code might not like teflon tape in your neck of the woods.

Here in KS use of teflon tape is no problem for NG . . . assuming no leaks!

See EDIT above to cover code specific by location. However, both Colorado and Kansas allow either Teflon tape or pipe dope for sealing black pipe.

The reason you don't want teflon is that as you make up the joints the threads cut the teflon and you end up with "threads" of TT which can then move to your gas valve. If they become bound up in the valve it cannot close completely. If you do this use Rectorseal. A lot of people think that IPS (iron pipe size) threaded joints are actually sealed with the pipe dope. The actual reason you use pipe dope is to lubricate the threads so the joint can be further tightened and the metal to metal makes the joint. As an example try to hand tighten a 90 to a ****** and see how far you can turn it in without the dope and then with.

I think your existing 3/4" line is to small with the addition of the garage. Run new 1" from the meter to the current equipment. I'd probably run 1" all the way and drop tees as I went, because I like to add equipment to the house.

BTW, at 6k ft you will need a manometer to reset your gas pressures. You have to derate the appliance due to air density. This is a used appliance and the reason it is being sold is that it may not have run properly due to not being properly calibrated for your area. It is worth talking to the utility to get an idea of the spec gravity of the fuel they are running to know for sure.

All of this leads to me say that, once again, Badger is leading you correctly.

 

[rlitman]

This comes up time and again. NPT threads have a helical leak path. They will not seal without something in there (NPTF is different, however that will never be found on a steel-steel connection, as it required thread deformation).

Proper use of teflon tape (and to some extent dope too), requires leaving the first thread of the male threads clean. Done this way, there is no risk of teflon threads working their way into places they do not belong. Regardless, teflon tape is an automatic inspection failure in my neck of the woods. More importantly, look closely at the ratings written on teflon tape spools, and you will note that most teflon tape is not rated to be used with natural gas, so this is a blatant code violation (yellow is one exception).

 

[CNGsaves]

That's fine for you all in NY . . . . sure that CA might be strict on west coast as well. Lots of code are different on both coasts.

However, the OP is in Colorado (which is next door to KS) and both states allow teflon tape for NG on black pipe. Teflon tape is sold in Lowes and Home Depot and wholesale plumbing supply houses, including Winnelson in Denver.

Virtually impossible that teflon tape could get into inner workings of pipe (ie into the NG gas flow) when properly applied to male thread (ie skip the first thread).

Guess this is just a difference between states. No biggie since no leaks.

ACTUAL ROLLS of Teflon Tape Being Sold in KS:
Pulled all the teflon tape rolls I could find that I had bought as follows:
a) blue cover w/ white teflon tape (Brand: CFPC - - Made in China) - - - no special instructions
NOTE: This tape is used for steel pipe threads like air compressor fittings, etc.
FYI: I would NOT use this one for Natural Gas.

b) yellow cover w/ yellow teflon tape - - had 2 brands
Plumb Pak - - - - made in Newington, CT - - - - labeled as "Gas Tape"
UL Listed Seal Material 28DZ - - -special instructions: "For use on threaded joints of metal pipe (not exceeding 1 1/2 pipe size) in assemblies handling gasoline, petroleum oils, propane, butane, naptha, benzene, kerosene, natural gas (pressure not over 100 PSIG) a minimum of two full spiral wound wraps is required. [File number MH30084]

 

[James-W]

I have a 3/4 inch black pipe coming from the gas meter into my house. I have a 70,000 BTU furnace and a 40,000 BTU water heater running off the 3/4inch gas line.

When I built a new garage, I wanted to put in a gas fired heater and I decided on the Hot Dawg brand modine type heater. I called the gas company and they sent out a guy to look over the situation and give me some ideas as to what I had to do to run the gas line.

The gas company guy spent quite a bit of time looking everything over and then he said that I basically had two choices and either way would have good and bad points to it.

The first option was to use the existing meter. He said the 3/4 inch pipe running from the meter into the house was too small and would have to be replaced with at least a 1 inch pipe. The 1 inch pipe would feed the furnace and the water heater and then be split off and a 3/4 inch pipe would have to come out of the house and be buried and run out to the garage. The gas company would not do the work, I would have to hire someone to do it, or do it myself. But the guy also said the codes for doing this were pretty strict and it would be difficult for me to do it myself without at least getting some professional help.

The second option was to run a separate gas line from the street to the garage and have a separate gas meter. The gas company would do this for free, but then I would have an extra meter charge every month.

I called the heating and air-conditioning people who installed our new furnace and central air a few years ago, and they sent a guy out to check it out. After checking everything over and doing a whole lot of measuring, he went back to the shop and came up with a price for doing the gas line work. He said it would be right at $1,200 to change the gas line running into the house to 1 inch and then run a pipe outside and bury the gas line going to the garage. He said to do this is not a simple job, you need a permit and you have to do it exactly right or it will never pass inspection.

After spending some time and thinking it over carefully, I decided to have the gas company run a separate line to the garage and install a second meter. They came and did the job, it didn't cost me anything, but now I have the cost for a separate meter every month which will eventually cost me more than to have it done the other way.

The heating and air-conditioning people came and installed the garage heater and connected it up to the new gas line. They did a super job, VERY professional, and everything works perfectly. I have had no problems what-so-ever with it. I leave it turned down to 50 degrees at night, or when I am not working out there, but when I am working on a project I turn it up to 65 degrees, or even 70 degrees if my wife wants to work out there too.

 

[ForceFed70]

I ran my own underground gas line to my shop as I didn't want to pay a 2nd meter fee every month. I even switched to a 2PSI gas system in the process. Permits, inspections, etc... no issue.

Really, It's not all that complicated. The hardest part IMO is threading the damn pipe. Most people don't have access to a good pipe threader.

The underground yellow plastic gas line was super easy to work with.

 

[CNGsaves]

I have a 3/4 inch black pipe coming from the gas meter into my house. I have a 70,000 BTU furnace and a 40,000 BTU water heater running off the 3/4inch gas line.

When I built a new garage, I wanted to put in a gas fired heater and I decided on the Hot Dawg brand modine type heater. I called the gas company and they sent out a guy to look over the situation and give me some ideas as to what I had to do to run the gas line.

The gas company guy spent quite a bit of time looking everything over and then he said that I basically had two choices and either way would have good and bad points to it.

The first option was to use the existing meter. He said the 3/4 inch pipe running from the meter into the house was too small and would have to be replaced with at least a 1 inch pipe. The 1 inch pipe would feed the furnace and the water heater and then be split off and a 3/4 inch pipe would have to come out of the house and be buried and run out to the garage. The gas company would not do the work, I would have to hire someone to do it, or do it myself. But the guy also said the codes for doing this were pretty strict and it would be difficult for me to do it myself without at least getting some professional help.

The second option was to run a separate gas line from the street to the garage and have a separate gas meter. The gas company would do this for free, but then I would have an extra meter charge every month.

I called the heating and air-conditioning people who installed our new furnace and central air a few years ago, and they sent a guy out to check it out. After checking everything over and doing a whole lot of measuring, he went back to the shop and came up with a price for doing the gas line work. He said it would be right at $1,200 to change the gas line running into the house to 1 inch and then run a pipe outside and bury the gas line going to the garage. He said to do this is not a simple job, you need a permit and you have to do it exactly right or it will never pass inspection.

After spending some time and thinking it over carefully, I decided to have the gas company run a separate line to the garage and install a second meter. They came and did the job, it didn't cost me anything, but now I have the cost for a separate meter every month which will eventually cost me more than to have it done the other way.

The heating and air-conditioning people came and installed the garage heater and connected it up to the new gas line. They did a super job, VERY professional, and everything works perfectly. I have had no problems what-so-ever with it. I leave it turned down to 50 degrees at night, or when I am not working out there, but when I am working on a project I turn it up to 65 degrees, or even 70 degrees if my wife wants to work out there too.

Sounds like the HVAC company that did your new furnace a few years ago should have told you back then that main gas line from meter was undersized. That would have been proper time to upsize to 1 1/2" from the meter to mechanical room (ie near furnace). That would have been an affordable fix when everything was tore up anyway.

Here is KS the meter charge is crazy at $16 a month so $192/yr just for meter charge PLUS the cost of natural gas. Thus, I'll be running my own buried yellow plastic pipe to garage for my heater - - - no extra meter charge for me and lost cost NG for garage heat!!

 

[ebstein]

Some more info to help: There's about 36 ft of 3/4" black pipe from the meter to my water heater and furnace location. I have Tee'd into the line at that location and it will require about 30 ft to reach the heater location. So my question is would 1/2" line be adequate or should I use 3/4" line due to the over-all length of run from my meter to the garage heater. Maybe more importantly is my recently realized concern if a 3/4" main supply line will support a 70,000 BTU furnace, 40,000 BTU water heater and now add the 60,000 BTU garage heater for these distance of pipe runs. Again I don't know how my elevation affects these numbers/calculations.

you will have no problem at all...run the 30' in 1/2"...KeepItSimple...