Pipe Insulating off Mains to Radiators

ww

The mains are insulated with the old type cardboard covered insulation with the metal straps. I read that this old insulation could be covered with some plastic wrap. What kind of plastic wrap and what are procedures?



The smaller pipes off the mains to the radiators are not insulated. From my readings here this is no good. The heat loss will be great and will hold back the steam from reaching the top floors efficiently.



 I saw that the pipe insulation costs 10 bucks for 3 feet at home depot. I'd say there must be 60 feet plus or minus not insulated..that's roughly 200bucks. I read you can use home insulation and wrap the pipe.



Wondering once this insulation is done do you think it will dramatically make a big difference?..From what I read yes but would like to hear from expert on experiences in regards to this.



If I do this what are my choices as far as insulation wrap to use for this and specific R values used..what kind of tape to hold it that will withstand the heat?



Should I go to plumbing supply instead to get what I need? Any help will be appreciated.Even if you can direct me to an article,link or manual. Thanks

SWEI

Encapsulating the corrugated stuff

is easiest with heavy bodied latex paint (or an elastomeric coating, which is basically a thicker version of the same with some extra UV inhibitors added for rooftop use.)

ChrisJ

Forget homedepot

Forget home depot and the 1/2" garbage they sell.

You can buy 1" quality stuff from http://www.buyinsulationproducts.com/ for less money than Homer wants for the 1/2" stuff.

Jamie Hall

I have used

the kind of plaster impregnated gauze used by surgeons etc. to wrap the old cardboard stuff -- which may have asbestos, by the way.  The plaster makes a hard, impervious tight seal which is usually acceptable remediation.



I would do as much of the runouts as is reasonably feasible.  I wouldn't get carried away to the point of ripping out finished woodwork or plaster, though.

ChrisJ

Cardboard?

Jamie,



I thought asbestos insulation looks completely different than cardboard?   I don't know about pipe insulation but 1920s-1930s GE Monitor top refrigerators use cardboard insulation in the cabinets.  No asbestos there, just cardboard which apparently has almost the same R value is fiberglass. 

I'd assume (magic word here) that if it looks like cardboard, it probably is. No?



Maybe not.

This website claims this is asbestos. 

http://www.looksmarthomeinspections.com/images/Asbestosinsulation.JPG

SWEI

Cardboard Stuff

Translation:  Corrugated asbestos-impregnated (just a few percent IIRC) paper.  Rewettable plaster will work, but I'm honestly not sure how it performs with modern testing methods.

Mike Kusiak_2

Aircell Asbestos Insulation

As far as I know, cellulose based cardboard was never used for steam pipe insulation. What the photo in the link shows is aircell asbestos pipe  insulation, which is made of almost pure asbestos fiber. This is actually corrugated asbestos "paper," which is made like cardboard but substitutes asbestos fiber and a binder for the usual wood pulp fibers.



And Chris, I would also assume that the insulation in your monitor tops is also asbestos rather than organic cardboard. Asbestos insulation was used in all sorts of consumer products in the 20's and 30's, from toasters and irons to stoves and radio cabinets.



You can confirm pretty easily by hitting a piece of it with a blowtorch flame. If it burns and chars then it is organic paper. If the flame won't touch it, then it is certainly asbestos.

ChrisJ

Cardboard

Mike,

Does the asbestos (cardboard) look the same as normal? The stuff in the monitor tops is brown and looks like normal cardboard. I think we also found in GE data that it was said it was corrugated cardboard. Perhaps asbestos was only used around heat and boilers?



I don't have any to test but I think one of our members has some as he replaced it with foam. I'll see if he can hit a piece with a torch under safe conditions.

Mike Kusiak_2

Refrigerator insulation

Asbestos cardboard usually looks much whiter than the normal paper kind, but for use as refrigerator insulation it could be a blend?



The reason I was suggesting it might be asbestos is that due to condensation, the refrigerator insulation typically gets moist and I would think that the organic paper would get soggy and rot in that application. 

ChrisJ

Ah

Well, we do know one thing for sure.

When it gets wet it gets soggy and falls apart. A few members have had that problem and it seems GE changed some things that allow the cabinet to breath into the inside of the fridge to help pull moisture out of it.



I asked if one of the members could try burning some of it just to see. If it does contain asbestos it would be better to know it than to not so it can be handled appropriately if being removed.

Orple

I've got just basic cardboard

Funny you should post this now. Just the other day, when I was looking in my floor joists to see how much of my pipes were insulated, I found a section -- tucked away under a finished ceiling -- that was insulated with just regular old corrugated cardboard, wrapped five times around. This one only done in one section, because a line of BX cable ran over it.



I don't think it's the best idea, but if I understand it correctly the combustion temp of cardboard is higher than the temp of steam. That said, I'm probably going to fix it when I insulate the pipes (soon), because it just doesn't make sense to me. FWIW.

rmoore007ri

insulation and big box stores

I'll second the recommendation for http://www.buyinsulationproducts.com/



The big box stores only have 1/2 inch insulation. You really want 1 inch for the near boiler piping and mains.



Plus this vendor shipped the wrong stuff recently. They corrected the mistake pretty much instantly and told me to keep what they had shipped. On another occassion I ordered the wrong stuff and they shipped the right stuff immediately and then credited my account when they got the return. (Proof positive that mistakes happen on both sides of the counter) . . .



They also have the right sort of tape and the kits for T's and unions and elbows for the near boiler piping.

ChrisJ

Buyinsulationproducts

You know what kind of confuses me but is pretty much moot.

I just ordered a fair amount more from buyinsulationproducts.com and the pipe insulation I got is yellow where all of my previous stuff was brown. Did they switch vendors or something? I want to say my first batch was Knauf earthwool. I guess this stuff is from someone else. Either way, still an amazing price on 1" thick stuff.



I've spent around $500 there and have been happy with all of my purchases. They did make a mistake once but corrected it instantly with zero hassle.

JamesC in Stamford CT

Does insulation make a differnce?

You wrote: "Wondering once this insulation is done do you think it will dramatically make a big difference?..From what I read yes but would like to hear from expert on experiences in regards to this."



I am NOT an expert. Just a homeowner. But when I bought the house the main pipes were bare and the basement was hat and my system was not balanced. After I insulated the mains, the heat went where it was supposed to, and the last radiators (furthest from the boiler) now all of a sudden got fully warm. I can't say how much money it saved since it's been only a year, but I notice the basement is not hot and the rooms are warm.



And yes, I agree with the others, do not get 1/2 inch. Get one-inch fiberglass.

bill714

What a score

Here's what I did.

I look around and saw some guys working on a building using 4" vinyl back fiberglass.  I ask if they had any scraps I could have They gave me a 50 foot roll!!

I went to D&D and got them all coffee and donuts

So I cut it in to 6 foot strips and duck tape in place 

ChrisJ

roll?

A roll of fiberglass pipe insulation?

bill714

blanket

Hi Chris, They were using 4 foot wide blanket insulation 

ww

this pipe insulation looks like cardboard. when i put a torch on it this is what happened...got charred.

Abracadabra

ChrisJ said:

Buyinsulationproducts

You know what kind of confuses me but is pretty much moot.

I just ordered a fair amount more from buyinsulationproducts.com and the pipe insulation I got is yellow where all of my previous stuff was brown.
</blockquote

My recent orders from there have been yellow fiberglass from owens corning. Just finished a pretty big insulation job last week. 5" and 6" mains with 2-1/2" returns. 8" steam header with 6" risers. That was fun. 20+ boxes of insulation.

Abracadabra

ww said:

this pipe insulation looks like cardboard. when i put a torch on it this is what happened...got charred.

that's asbestos. You only charred the outside cloth jacket. The asbestos is not in the jacket that charred.. It's in the corrugated section. Also, try getting cardboard red-hot like in your picture. You'll blow a hole thru the cardboard.

ww

ok thanks..i was wondering that..since someone mentioned previously it could be organic paper if it burned or charred which it did. i took that off using some plastic around it and didn't see any residue around pipe and there was a split in the insulation and it easily came off.

i saw alot of videos of crews taking off pipe insulation and see that they usally cut it off and it falls in bags and is wetted down..and it is really thick with a cloth coating on the outside..and they use gloved bags,plastic around the rooms,pipes,special suits and masks and machines causing negative pressures. it just didn't look like the same stuff they were taking off.