natural gas ventilation question

[vansguy285]

Hello and happy new year!

I have faced fiberglass batts pressed into my basement ceiling joists and the new gas line is boxed in. I will be installing an aluminum sheet wire mesh vent on the underside of the sheetrock box to allow some ventilation from the bottom. Since gas rises, my concern is that the insulation will not allow proper ventilation in the event of a gas leak. I also hear that Fiberglass insulation can give off static electricity, which could ignite gas

Should I
1 leave all the insulation alone?
2 remove a section of the insulation from directly above the gas pipe, ( reaching through the to be installed aluminum sheet mesh) to allow some more ventilation
3 or should I remove ALL the insulation from ALL the ceiling

Numbers 1 and 2 would be practical. The ceiling is up already but if I have to I will remove it.

 

[Twowaxhack]

If you have a leak and the gas can’t escape and it builds up and is ignited some how then you’re screwed.

The trick is not to have a leak in your situation. Good luck, gas has its dangers.

 

[Rossando]

I am sorry what's this ventilation pipe for? Is this vent pipe for a natural gas appliance/fixture?
-what material are you installing? example: single wall sheet metal?
-where is this pipe terminating?
-in the soffit framing i see a steam line thats connects to your condensate return right at the wall.
-black steel gas pipe maybe 1 or 1 1/2
-1" copper water pipe( maybe cold water domestic line)
If you put anything in there like flue pipe vent ductwork it can be done. You need specific pipe/duct materials and to keep and maintain certain clearances in order to protect wires, pipes, wood framing, lastly insulation.
Air circulation/bathroom exhaust fans or HVAC ductwork have less technical restrictions.

 

[breplum]

properly installed gas piping never needs "ventilation".
However, you appear to have natural draft appliances, which do require combustion air.
do you have adequate combustion air?

 

[vansguy285]

Thank you so much for the replies.
At this point, I really don't know what to do moving forward and I'm very distressed. The stakes are high. Almost all the similar installations I see DO NOT have insulated ceiling cavities and I assume this allows more air circulation, whether or not that was the intention. I agree with you twowaxhack that having no leaks is the best insurance.

At a minimum I WILL be installing the sheet metal vent screen along the bottom of the soffit and add some air vent holes in the sides of soffit.

Would removing the insulation allow for better gas escape in the event of a leak?

Is static electricity a concern for fiberglass insulation ingniting gas ?

The last pics show an area adjacent to soffit where the gas pipe continues along a joist bay but again has been covered by insulation. Is that a potential for gas build up as well?

 

[Rossando]

What the....I still have no idea what this thread is about. This guy is making a big deal about what again? Mr operator please let us know what you are doing or trying to do? What is the premise or main concern? Aswell what are you installing?

 

[vansguy285]

Hi Rossando,
Thanks for your help and time.


The project is basically all completed, with celings up however looking back I am very concerned that there is not adequate " air flow" where the gas pipe is installed, (both inside the soffit and in the joist adjacent to soffit), to allow for proper dissipation of gas in the event of a leak. I know that gas rises and was wondering if all the fiberglass insulation is blocking adequate airflow. Would a typical potential leak at a joint or pinhole on this size line at 1/4 psi, be able to float up around the insulation before reaching explosive levels of 5-15%

I'm just not sure the ventilating on the bottom with said mesh screen is enough since gas does rise.

I would be willing to remove some or all of the insulation if it were to help. Another concern is that fiberglass insulation can create static electricity which may arc and ignite a gas leak



Thank you again for your time and insight.

Does anyone know of any experts in this area, ie gas safety engineers who could chime in too?

 

[havasu]

Not without disclosing what the gas is being used for. We are not narcs, we really don't care, but an honest answer needs an honest question.

 

[vansguy285]

Hi Havasu,
I'm not sure what you mean. The gas is used to run a stove, water heater and steam heating.
I just want to know what is the best thing to do here given my concerns.
Thank you

 

[Twowaxhack]

Basically you’re worrying about a potential gas leak in a closed in space.

That’s a valid concern.

Ok, so ventilate the space. Do it however you’d like. Natural gas does rise, it’s lighter than atmosphere. Propane gas is heavy and it drops…..

Fiberglass insulation isn’t going to ignite a gas leak.

Good luck

 

[vansguy285]

ThanksTwoWaxhack for acknowledging me…
Do you think removing All the insulation throughout the whole ceiling is overkill, or do u think just around the pipe is sufficient?
In all honesty what would u do?

 

[MicEd69]

Hi Havasu,
I'm not sure what you mean. The gas is used to run a stove, water heater and steam heating.
I just want to know what is the best thing to do here given my concerns.
Thank you

Was the piping installed by a professional? The most likely leaking point is at the appliance connections. I think you are worried about something that is never going to happen. My suggestion is to leave the installation, install the mesh screen, and purchase a gas detector that will alarm well before any gas leak results in a problem.

 

[vansguy285]

Thanks MicEd,

It was installed professionally and I agree the chances of leak are remote but the potential damage is high. I would be able to pull some insulation above the pipe off once the mesh is installed if desired. What do you think about this?

I will definitely be getting gas detectors but not sure where to install it because it would sit below the pipe level for 1/4 seasons. I could not put it inside the soffit in winter because it would overheat from adjacent steam pipe?

I was also thinking of installing 1 near floor level above to capture potential rising gas from floor voids below.

I really appreciate your insight and opinion. I need to made a decision soon

 

[breplum]

Gas doesn't just start leaking. Once tested, it is NEVER an issue. OP is obsessed, somehow and for NO REASON about leaks, which is completely absurd.

 

[vansguy285]

I agree this has been stressing me, thats why I am asking other people's opinions and experiences, to gather enough information to make an educated decision moving forward.

Thank you

 

[MicEd69]

As long as you don't use the gas pipe as a clothes rod or an anchor point for a chain fall, it will be fine. The gas detector and your nose will notice any gas WELL before an explosive limit is reached. Leave the insulation in place and install the gas detector next to the mesh somewhere along the line to calm your nerves. It really isn't something I would ever do, but it appears you need to do something, or you will get an ulcer. The hole in the floor where the gas line come up to the stove is often not sealed as it doesn't have to be. If it is sealed, carefully cut an opening along the vertical pipe and place one there if you must. But you will likely be getting nuisance false alarms which will make you feel even worse. You are really worrying about something that is so unlikely to happen, that most if not all of those responding would not change a thing and would be TOTALLY comfortable leaving things as is.

Do you drive or ride in a car or bus on the highways?

 

[Twowaxhack]

ThanksTwoWaxhack for acknowledging me…
Do you think removing All the insulation throughout the whole ceiling is overkill, or do u think just around the pipe is sufficient?
In all honesty what would u do?

I’d insulate it and not worry about it if the work was performed by a competent installer and was tested.