replacing ductwork

What have I done · 05-29-2007, 10:05 PM

I am renovating an old farmhouse. Basically gutting evrything. It originally had an old oil furnace wich I will be upgrading to a high eff. propane unit.
Some of the rooms on the second floor have 2 heat registers and there is only 1 cold air return for the 2nd floor.
While I am renovating I would like to add registers and cold air returns. Is their a program or a rule of thumb to adding ductwork? I am basically scraping all the old and want to replace with all new.
Thanks for any help steering me in the right direction.
I will be having pros do the furnace and central air I just want to have the gruntwork done with all the ducktwork run down close to where the new furnace will be

moneymgmt · 05-30-2007, 10:11 AM

I guess I don't completey understand what you're asking here; rule of thumb for what? Duct placement? Duct sizes? How/where to run them?

I'm assuming that "gutting everything" means you're tearing everything down to the studs? For a job like this I hope so....

What have I done · 05-30-2007, 10:45 AM

Yes exactly! I need help or a program to determine Duct placement? Duct sizes? How/where to run them?

I figure each room need a supply how many cold air returns should there be?

Gerry Kiernan · 05-30-2007, 12:00 PM

Hi

Even if you plan to do the bulk of the work yourself, it would be a good idea to consult an HVAC [household ventillation air conditioning] expert. He could design a system for you. Will cost a few bucks, but you will hopefully get better results. Local heating contractors could probably help you out.

Gerry

moneymgmt · 05-30-2007, 12:23 PM

I have to agree with Gerry here; with that many questions you need to consult with a person who can come to your home and see what you're dealing with. To be up to code there are several issues that I can't even begin to get into here. There is no way we can tell you "where to run them" on a forum posting without seeing what you see. Sizing goes directly in line with that. I'm sorry, but you have a very complex issue here.

bigMikeB · 05-31-2007, 08:22 PM

First off HVAC stands for heating, ventilation and air conditioning. Secondly, I would try an HVAC supply house for heat loss, heat gain and duct design calculations, this is the part of the job that even well established contractors mess up with thier rule of thumb designs.

Gerry Kiernan · 05-31-2007, 09:42 PM

Hi Big mike b.

You are absolutely correct on what HVAC stands for. I knew I wasn't too sure of the H, but couldn't for the life of me remember until later in the day. Good advice on the supply house. I didn't know there was such an animal.
Thanks for the corrections.

Gery

Gerry Kiernan · 06-02-2007, 06:56 PM

I am not trying to get the last word in here, but I think the bottom line is this. You are going to spend a lot of money to buy your high efficiency propane furnace, you are going to spend a lot of money on duct work, and you are going to spend a lot of money on refurbishing. I think Big Mike had a good idea when he suggested using the sercices of a heating/ventillation supply house to help you plan, if they provide those services.
Before you start buying the stuff get some professional help, from whatever source, in planning the installation. The calculations for an HVAC installation are quite complex, and if anything is worked out wrong you could be disappointed.

Gerry

05-29-2007, 10:05 PM	#1
What have I done Member Join Date: May 2006 Posts: 244	replacing ductwork I am renovating an old farmhouse. Basically gutting evrything. It originally had an old oil furnace wich I will be upgrading to a high eff. propane unit. Some of the rooms on the second floor have 2 heat registers and there is only 1 cold air return for the 2nd floor. While I am renovating I would like to add registers and cold air returns. Is their a program or a rule of thumb to adding ductwork? I am basically scraping all the old and want to replace with all new. Thanks for any help steering me in the right direction. I will be having pros do the furnace and central air I just want to have the gruntwork done with all the ducktwork run down close to where the new furnace will be

05-30-2007, 10:11 AM	#2
moneymgmt Member Join Date: Apr 2007 Location: 'burbs of Detroit, MI Posts: 450	replacing ductwork I guess I don't completey understand what you're asking here; rule of thumb for what? Duct placement? Duct sizes? How/where to run them? I'm assuming that "gutting everything" means you're tearing everything down to the studs? For a job like this I hope so....

05-30-2007, 10:45 AM	#3
What have I done Member Join Date: May 2006 Posts: 244	replacing ductwork Yes exactly! I need help or a program to determine Duct placement? Duct sizes? How/where to run them? I figure each room need a supply how many cold air returns should there be?

05-30-2007, 12:00 PM	#4
Gerry Kiernan Member Join Date: Apr 2007 Posts: 61	replacing ductwork Hi Even if you plan to do the bulk of the work yourself, it would be a good idea to consult an HVAC [household ventillation air conditioning] expert. He could design a system for you. Will cost a few bucks, but you will hopefully get better results. Local heating contractors could probably help you out. Gerry

05-30-2007, 12:23 PM	#5
moneymgmt Member Join Date: Apr 2007 Location: 'burbs of Detroit, MI Posts: 450	replacing ductwork I have to agree with Gerry here; with that many questions you need to consult with a person who can come to your home and see what you're dealing with. To be up to code there are several issues that I can't even begin to get into here. There is no way we can tell you "where to run them" on a forum posting without seeing what you see. Sizing goes directly in line with that. I'm sorry, but you have a very complex issue here.

replacing ductwork