snow load on roof?

[trtrtr]

Hi all, I need to figure out what the snow load is on my roof. Any ideas how to do this figuring? Is there a website with average load info or location-specific info? I am in Winthrop near the library.

Thank you!

[maxjmclaughlin]

Not sure about a source to find that kind of info, but in the past I’ve isolated a 12”x12” column of snow on my roof, put it all in a contractor trash bag and weighed it to get a sense of my lbs/sq. Ft. amount at that given time.

[Slade]

If you have real concerns about hitting your snow load limits, I'd think the first priority would be to get some of the snow off right away and not worry too much about how close your are to hitting the limit.

Bob

[trtrtr]

Thanks to both.

Not really worried that I am hitting those limits at this point… Just trying to figure out what the limits are and how to know where I am at.

Not even sure what kind of professional I might consult. Any ideas?

Thanks!

[maxjmclaughlin]

I’d say a structural engineer would be the best resource. Maybe a seasoned general contractor could help you understand your structures roof loads too? If you have plans/drawings for the structure the engineering plan set should have this info. Lots of factors/variables: trusses vs rafters and the spacing of them, thickness of roof sheathing, how far out do your roof overhangs stick out and in what way are they supported (lookouts or knee braces/corbels), etc.

I know there are estimations for weight of snow if you poke around on Google you can find them (ex weight of 2feet of fluffy light snow, weight of 3 feet compacted heavy/icy snow) but to truly know the exact weight of the snow load sitting on your structure would take some actual measuring in my opinion.

[Slade]

Excellent analysis max. The first step might be to know what the code requirements were when the house was built. I believe our home was built when the code for our area said 70 pounds per square foot live load.

Bob

[moose]

Am I missing something? It seems you could remove/collect one square foot of accumulated snow, bring inside to melt, weigh it or measure it by the gallon. One gallon water equals 8lbs. Repeat after any rain events.

[trtrtr]

Thanks, folks. I appreciate all this info and thoughts.

I will def do the measuring thing.

House is fairly new and was built to code — 75 lb/sq ft.

This is my first house in a snowier area so just figuring out the basics..

Speaking of basics, this is also my first heat pump. Does anyone know what is up with Fisher Refrigeration? I have heard they do great HVAC work but their phone number doesn’t seem to work and I am not confident about the email I dug up.

Thanks!!

[Slade]

Just called Dave's cell number and it seems to be working fine. What number were you calling?

Bob

[trtrtr]

Thanks! You were the charm. Just tried again and got through.