Pipe Insulation

Long Beach Ed

...money spent at Home Depot is money wasted.

Steve Garson_2

Pipe Insulation

My steam mains are insulated with the 1/2-inch fiberglass from Home Depot. From what I read on-the-wall, I should have thicker insulation.

I measured the circumference at 11-inches, so the OD is 3.5-inches. Is there a standard pipe insulation that will fill over what I have now? Any other suggestions on how to cost effectively add insulation?

Brad White_17

Insulation

For the pipe sizes you describe (probably 2-inch IPS) the OD is close to that for 3-inch pipe. If 2-inch, most model energy codes recommend 2-inch insulation.

You can get insulation sized for 3-inch pipe in 1.5 inch thickness to bring you up to snuff. Given your habit for shopping H.D., you will have to travel to a commercial supplier to get the right stuff. You can do a web search for such a firm but what is more useful than me guessing over the web is to seek an insulation nesting chart. I think most manufacturers have them posted (Knauf, Certain-Teed, Owens Corning, Manville, etc.). These nesting charts have combinations of pipe size, existing covering thickness and subsequent coverings available.

If you are doing a lot of this and do not want to guess, invest in a Pocket-Rocket pipe measuring tool under the "shop for books and more" link on this site.

A bit of advice: Nesting is not always perfect and you may find a slightly loose fit ("rattle"). It might be 1/8 of an inch. If that is the best you can do, the key is to seal the joints to stop air leakage, and offset the joints from one layer to the next. No air leakage is key, so do the fittings too. Your supplier can advise you here also.

Good Luck!

Brad

pippi Z

insulation

I'm a homeowner/doityourselfer and I started measuring the pipe in my basement for insulating a double pipe steam system today, It is actually an old industrial building, so it is quite large with a lot of pipe running all around the basement before it makes it's way upstairs. I had been doing a little research on the internet and read some suggestion to insulate the return lines. This didn't make much sense to me. Also, I feel pretty ignorant of what type of insulation to use. I don't have a lot of money - however I know this will save me in the long run- so I know it is an investment. Our main is a 4 inch pipe - do I need to go through an industrial supply place? Any info on the pros and cons of different types of insulation would be much appreciated.
thanks
Pippi in Providence

Brad White_9

Pippi,

You may take what is written above and go with it, especially the part about buying a Pocket Rocket measuring tool. I am in Boston and use Homan's Associates for insulation supply. They are pretty well distributed but there are others. Not sure if they are in RI.

Moulded fiberglass is what you want, with all-service jacket ("ASJ"), for finish. Elbow and fitting covers and inserts are available.

Your supplier can guide you to what the RI Energy Code requires but model codes generally agree that any pipe of that temperature starts at 1.5 inch thickness then jumps to 2 inch thickness for pipe over 1.25 inch diameter (make sense? Hope so!) 2-inch thick insulation covers your 4-inch pipe size. DO measure with the Pocket Rocket though. You might have some 3.5 and even, yes I have seen it, 4.5 inch pipe. Obsolete sizes you will be hard pressed to cover neatly. Save yourself the hassle.

Return lines: Yes, insulate them. Two reasons:
1) They are hot. They contribute heat to a space whether you need it there or not. Why not take control of your heat? That is the idea. And,

2) They are hot. If in areas of human contact especially, you or a child or elderly person could be burned. The latter before you know it.

Suggestion: This showed up as a question within another thread. You may want to post it as a separate question of your own so it does not get lost.

Good Luck! Providence is one of the Great Cities.