Safe temp for pipes in the eaves: how much insulation?

Old 02-20-19, 07:37 AM
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Safe temp for pipes in the eaves: how much insulation?

Recently had a frozen pipe, I fixed it but then it dawned on me why it burst.

House has a gable roof with dormer windows.

The 3rd floor is finished with appropriate insulation between rafters and with hard insulation and appropriate flow from soffit to the small attic at crown of the 3rd floor by way of rafter vents which are then covered by soft roll insulation.

They constructed it so that there was storage space in the eaves I could access (like a crawlspace)

BUT they also ran the pipes for the baseboard heaters thru those eaves crawlspaces

Either way the pipes are currently covered with pipe insulation now , previously they were not.

Using a remote temp sensor that tracks and records 24/7 it hit 45 degrees in those eaves when it was 11 degrees last night and hovers around north of there and i'm sure drops more when we are in single digits with wind.

I made sure to pack with insulation any air flow from soffits into those crawlspaces.
and covered all pipes with pipe insulation

However even after that it still reads 45 degrees when it hit 11 degrees outside

Is that too cold for the pipes? room is kept at 61 degrees,
I could open the doors to those crawlspaces but I cant rely on my memory to always remember to open those doors when it gets cold ( I forgot this year this the burst pipe, when the doors are open it reaches 56 ish degrees)

Should I put more insulation over those pipes( it would only cover the top not bottom as pipes only have clearance of 3/4" from the floor.

Thank you
Old 02-21-19, 11:29 AM
Join Date: Oct 2008
Location: New England
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When insulating pipes you always want the insulation between the cold and the pipe, not between the pipe and whatever source of heat there is. 45 will not hurt the pipes unless you block it with insulation.

Without being there I would suggest you add more baffles so the soffit vents can continue to provide air flow under the roof deck all the way to the small attic up top. Then insulate those rafter cavities and cover with sheetrock.

Pictures might allow better advice.


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