Okay, I have a bathroom above my two car garage and my sink and toilet pipes kept freezing up here in New Jersey. I cut two holes in my garage ceiling to get to the pipes to insulate them..

There was no insulation behind the pipes facing the outside wall of the house so I was getting a draft coming in from outside. So I toke 1/2" foam pipe insulation and put that on the pipes whereever I could get to them. I ductaped the insulation on to secure it there. Home Depot didn't have 1.5" foam pipe insulation so I couldn't put that on. Then I took R-25 insulation and stuffed that tightly around all side of the pipes. I put it all the way back to cover over the soffit too. Well last night was bitter cold with like -15 degree F windchill. So the hot and cold water pipes for the sink didn't freeze, but the cold water toilet bowl pipe still froze last night. There is about a 3 foot piece of the cold water pipe that tees off and goes to the toilet. I couldn't get all of this insulated so I think I draft is still getting up in there or something.

My one concern however is, since this area I have to work in is very small, I couldn't just lay the insulation down like you are supposed to. I had to cut like 1 foot long pieces and stuff that in the hole around the pipes. So the pipes are completely covered on all sides by this insulation pretty tightely packed. Is this bad to have this insulation tightly packed around the pipes? will I get condensation problems in the summer?

Thanks

 

While tightly packed insul. losses some R-value, you will probably reduce

the cold air flow to the pipes this way. When you wrap a pipe with a

roll of insul., that requires a fairly snug fit to keep things from unravelling.

I don't think you will have troubles with condensation either. In order to

make condensation you would need warm air flowing around a pipe that

has cold water flowing through it. You'll have the cold water sometimes,

but hopefully, no air circulation if the insul. is packed properly. (I see a lot

of foam sleeves used to prevent frozen pipes, foam is only good for stopping

condensation problems)

 

okay that makes me feel better because I really packed and packed pretty hard R-25 and R-13 insulation around the pipes whereever I could reach. I also have that foam pipe insulation on the pipes too...

how does the foam pipe insulation stop condensation by the way?

I tried to stop any airflow I felt when packing in the insulation but I am sure there is still going to be some airflow... just not nearly what there was....

 

The insul. on a cold water pipe prevents heat transfer from the air to the

cold pipe surface in the same way that a foam cozy keeps your iced tea

glass from sweating in the summer. The foam doesn't rely on absorption

to work, it stops the condensation from forming. The tea glass also won't

sweat until you add the ice, or if you decide you'd like your iced tea when

you go ice skating, you won't have condensation either. Heres hoping

for no more frozen pipes.