Saturday, January 29, 2011

Snow Screed...Or, How To Float A Big Fluffy Slab

noun \ˈskrēd\ 1) A lengthy discourse (e.g., personal account, or rant); 2) A leveling device drawn over freshly poured concrete [Source: Merriam-Webster]. A screeded concrete surface is usually finished with a float. For this article (which itself is a screed), snow is the metaphorical concrete, the North wind is the screed, and the float is, well, ... an actual float.

January 26th-27th brought us yet another intense winter storm. In our area, the storm dropped about 14"of snow – not quite as much as we'd received two weeks ago. But the total snow accumulation for the month of January was about 52", setting a record for the snowiest January here since 1965. And cold temperatures ensured the older snow stayed around, so accumulations both on the ground and on the tops of structures were quite deep.This caused numerous collapsing roofs here in Connecticut, and many folks are making efforts right now to remove roof-top snow.

In a previous post, I'd written how my home faces north-west, the same direction (more or less) that winter storms tend to blow from in this area. My main roof has a 10" pitch and presents a large profile to the wind, causing lots of snow to blow over the ridge and get deposited on the rear and mud room roofs. Furthermore, the front of the house blocks wind at lower levels, often causing a large build-up of snow on the entry porch roof and in the front yard. So I wasn't totally surprised to see this after the storm:

Needless to say, I'm glad I sistered the columns with 2x6 Ts before the winter. They're not in the greatest shape these days, but I hadn't had time to properly replace them in the fall. The mud room roof also had much snow, and my first priority was to get both porches cleared, which I can safely do with a shop broom from overlooking windows. But what really worried me was the cumulative snow on the back main roof:

Furthermore, the current forecast calls for more snow next week, or possibly even rain. So I really wanted to remove as much of it as possible. I needed something like a roof rake, but with about a 40' extension. I'm not sure roof rakes actually come that long, but it really didn't matter, as no one around here actually stocks roof rakes, and supplies weren't expected until sometime the following week.

But it turned out I had something easily adaptable: A four foot magnesium concrete float and several sections of aluminum shaft that screw together. I ran out to Home Depot and bought a few more sections so I could get the total length I needed. A bit pricey, yes, but I was determined to get this all done as quickly as possible:

First thing I had to do was remove the attachment point from the float, re-orient it 90 degrees, and bolt it back on:

Then, I angled the attachment point at about to about 45 degrees, and screwed one of the aluminum sections on:

My reasoning was that this would enable the float to ride up over the surface of the snow on the up-stroke, and then anchor into the snow on the down-stroke, thus breaking chunks of snow free. I collected everything together, and then headed out to the back of the house:

Not long after, my good friend and nextdoor neighbor Gary Farrell came over to see what I was up to (I think he probably realizes by now that I'm a little crazy). Gary grew up in the Hawkins house, which his family had owned since about 1853, and he had been the steward of the place for a good many years until I bought the house from him in 2007:

While Gary watched with some curiosity, I made my first attempt to get the float up and anchored in the snow just above the eaves. Only two shaft sections were attached. It wasn't quite as easy to do as I initially thought it would be. Once I got it in place, I attached a third section:

It took six sections to get the float just beyond the ridge line, at which point, the float tilted a bit, requiring me to push it a bit higher and spin the shaft to straighten it:

Meanwhile, Gary went back to clearing his side porch roof. I was a little leery watching him up there, hoping the porch roof was strong enough to support his weight and all that snow. I offered him to try out my experimental method, but he seemed quite content to continue with what he was doing (like I said, he knows I'm crazy -- everybody does :-) :

But soon enough, I cut my first swath of snow with the float. I found that shimmying the float would easily dig it in, and then a slight up and down undulation loosened the snow and released a small slough:

Once I had cut the first swath, I drove the float upwards again and attempted the next one (you can see how some portions of the first few sloughs settled on the mud room roof):

Then, I momentarily anchored the float up on the ridge, and took a minute to rest (and snapped this photo, too, of course), while the float waited patiently:

Next, I worked the float over a few feet and began cutting the next swath:

Controlling the float was tricky and took quite a bit of practice. Sometimes, the float would want to veer off to one side, and I'd have to move quickly across the ground (not easy with a lot of deep snow underfoot) and get back under it to make it stop:

In general, the more surface snow removed, the more challenging the float became to control, as it would want to slide across the exposed lower slab, which was hard-packed and icy:

Another point of difficulty was the need to occasionally add or remove a section or two of shaft, depending on how high the snow was where I was standing, versus where I was trying to get the float positioned on the roof:

In this case, another pair of hands was indispensable, and Gary provided me quite a bit of help in getting the job done (in addition to taking some good action pics):

Toward the end of the afternoon, I managed to remove most of the upper layers of snow from the roof. In the photo below, I only needed to clear a bit more snow from the vicinity of the main stack vent, which was effectively buried. But I stayed well clear of the rake line, given the float's tendency to slide sideways:

Needless to say, there was a lot of new snow on the mud room roof. I went back inside and removed it from the safety of the windows. Only I needed a shovel in addition to the shop broom, because this fine, sloughed-off snow had set-up hard (in fact, exactly in the same manner that slough sets up like concrete after an avalanche in the mountains). There was also a lot of displaced snow all around the perimeter of the mudroom and house, which now needed to be removed:

But at least it wasn't on the roof any more, and I had no further concerns about additional precipitation during the coming week.

Some Important Points on Safety and Property Damage

Despite my relative success with this project, I don't necessarily advise my readers to attempt the same. There are a number of risks associated with undertakings such as this one, and although I was able to eliminate or minimize the major ones, this might not always be possible in another person's situation. The major risks include, but are not limited to:

  • Potential for electrocution. Aluminum is an excellent conductor of electricity. Sending a long aluminum shaft aloft while standing in wet snow could be a very dangerous thing to do in the presence of overhead wires (e.g., power company service drop, or feeder to an out-building), or any other sources of electric power. In my case, there were no electrical wires nearby, and my service drop is clear on the opposite side of the house. Had it not been, or had I needed to clear snow from the front roof, I would've requested the power company to shut my power off first, and not resume service until I told them I had completed my work. Otherwise, I never would've attempted this. On the other hand, there are several outdoor light fixtures just beneath the eaves where I was working, but I de-energized their circuits beforehand. Note that a roof rake with a wood, plastic, or fiberglass shaft is arguably safer, but still shouldn't be used in the vicinity of live wires, or any other electrical sources or fixtures. Remember: That shaft is going to have a continuous stream of water dripping down its length, and on to your hands and body.

  • Damage and/or injury from falling snow. Even though these falling sloughs were relatively small, we were surprised by the impact they made hitting the ground. There should be no bystanders (especially small children) or easily damaged property, in the fall zone. Furthermore, if conditions are right -- fresh snow, or fresh snow over a consolidated, older layer of snow, and a very steep roof – you have the potential for triggering a small avalanche, in which more snow than you're expecting can suddenly free itself from the roof. The reason why I used so many extensions, in fact, was to deliberately distance myself as far as possible from the falling sloughs.

  • Damage and/or injury from the shaft/float. As I mentioned earlier, the float was difficult to control, and had a tendency to slide sideways, as the extended shaft is not very rigid. Again, no one should be in the fall zone, nor at either end of the house. There is also a potential for the butt end of the shaft to hit you in the face or body, if not properly controlled. Finally, rain gutters and nearby windows are also at risk for damage.

  • Damage to roof shingles. It would be easy to tear or knock off more than a few shingles doing this. In my case, I had good reason to believe there was at least one hard, base layer of snow covering the shingles, and took care not to penetrate it.

  • Build-up on other structures. As one reader pointed out in a comment, care should be taken to avoid too much snow building up on the roofs of smaller, attached or nearby structures. Be mindful of where the cleared snow is going and what it ends up resting on.

  • Physical injury. I found this work required far more physical exertion than shovelling heavy snow from a side walk. I wouldn't recommend it to any one who wasn't in exceptional shape.

The bottom line here is: If you're concerned about the quantity of snow on your roof, please hire a licensed and insured contractor to remove it!

Postscript [8 February 2011]

Since writing this article, it's become apparent to me that I could make the float less damaging to the shingles by attaching door weather stripping, or a section of foam pipe insulation, to the bottom edge.


AlexandraFunFit said... would infer that you are in exceptional shape, according to the parameters set forth here. And how warm was it, as you're not wearing any gloves? I didn't know aluminum shafts were deadly conductors - so I officially learned something. Ah, the heck with all that - who's that really cute guy with the blowing hair and black jeans?

Amy Good said...

John, it sounds like quite the adventure and I applaud your ingenuity. By the way, I would have never thought about needing to de-energize the exterior lights and would have probably gotten electrocuted early on. Kudos for trying and I bet it was one heck of a workout!

jb @BuildingMoxie said...

Is the amount of snow on your roof an indication of how well your insulation retro-fit is performing? (@SLSConstruction & @EnergyVanguard would be proud!) or is it just that friggin' cold in CT?

happy times, a great solution, flawlessly and funly documented. Thanks John!

juliana inman said...

I love the cautions at the end! Don't try this at home...

Ever the engineer, cousin!

John Poole said...

Hello AFF ~ Oh, if only I were in exceptional shape! Then I would not have spent all of Sunday seriously hurtin'! As for the temperature, it was pretty cold; but my gloves were wet and I wasn't getting a very good grip, so had to ditch the gloves after a while and just deal with it. And yes, anything made from aluminum is a good conductor and needs to be kept clear of electricity. And cute guy? What cute guy? No idea whom you're referring to...

Amy ~ Thanks! It was that large security light in the upper corner right under the eaves that caught my attention and reminded me. At first, I was just concerned about damaging it, and then I thought "Oh yeah, there's electricity in there...Better shut them all off!"

jb ~ Hey, bud! Thanks for all the great words. But energy retro-fit? What energy retro-fit?! You had to notice! Actually, it had more to do with the fact that there was literally about 2+ feet of snow on the roof, and that I generally keep the heat low, anyway, to prevent waste, and also keep the attic ventilated in winter, and that there is almost no heat on my second floor (only a single register -- seriously). In time, and with a lot of building moxie, that will all hopefully change!

Cousin Juliana (Elinore) ~ Hey, you know us as we say, not as we do! Whether it's clearing snow or sawing English Elms, we like to live on the razor's edge! Thanks for the visit and hope all is well...

Susan P said...

That sure is a big stick you got there John!

Susan P said...

Oh and btw, my mother got a roof rake yesterday from Stepney Hardware thanks to you tweeting about it the other day. We were just going to go out over the weekend to find one, but your tweet made her call ahead and reserve one.

You can expect the adoption papers in the mail. :)

Caffeinated Librarian said...

I've already told you this on Twitter but I'll recap here:

Any time you need a definition followed by the explanation of a metaphor BEFORE your rant, you're in trouble.

"It wasn't quite as easy to do as I initially thought it would be." You're going to put that on your tombstone, aren't you?

Any blog post that includes in its list of downsides for an activity "Potential for electrocution" should be a wake-up call.


John Poole said...

Susan ~ That's great! Glad my tweet helped your mom get her roof rake in a timely manner. Good luck with it, and let me know if I can be of any further help.

Caffeinated Librarian ~ My explication of the central metaphor of my article is there to assist readers who might not possess the specialized knowledge required to make the metaphor obvious. It's no different than when each verse of an epic poem begins with a short paragraph entitled "The Argument" :-D

And regarding your subsequent comments, I truly appreciate your concern for my safety, but my point was that the risk of electrocution is always there in the presence of electricity, and the solution is always to first turn all power off. Which is precisely what I did. It doesn't mean that such projects are necessarily to be avoided.

Also, my laundry list of potential dangers is there for the protection of less informed readers who might attempt to replicate what I've done without considering the risks. In my case, I made it a point to eliminate all these potential risks well in advance of actually doing the work (including keeping a safe distance from the house -- hence the use of the overly long pole).

Thanks for your comments, though..

AlexandraFunFit said...

As to the cute guy, I would give you a hint, but your high-grade obtusenicity (pronounce my new word) would still get it wrong. But his initials are J.O.H.N. No more hints. PS I really like the very last bit where you recommend a professional. I am a complete fool about electricity, so appreciate the caveat.

Caffeinated Librarian said...

You totally edited your comment didn't you. :-) Tsk.

As I told you on the phone: the difference between managed and unmanaged risk is that unmanaged risk is the risk you thought you'd managed...until it bites you on the ass.

I'm glad you're fine. But I'd rather have safe John than any amount of "Yankee ingenuity."

resenergy said...

A very important caveat should be the potential of overloading the shed roof below where you are initially dumping the overhead roof snow. I know of a case where a very pompous lawyer in Minnesota hired some high school kids to shovel off the snow from his office roof. Without detailed instructions, they proceeded to pile up the snow on the garage roof below which in turn collapsed onto his Corvette and Porsche. Ah justice!

John Poole said...

Resenergy ~ Thanks for commenting. Ah, high schoolers! Totally agree with you about loading up the roofs of connected structures. In my own case, the final snow build-up on my mudroom was generally within the range of what I knew the smaller roof could hold, based on past accumulations. But then, I was finished at this point. Had I more snow to remove, I would've cleared the mudroom roof before going any further. But much thanks for pointing this out. I've updated the list of caveats to include yours!

Cassie said...

Helloooo Cousin John! It's been ages so I had to come see you. Your snow float/scraper was ingenious and pretty funny to see in the pictures. Then when I read all your warnings I was laughing so hard I awakened Patrick! While I was up in Idaho in Nov. when we had over 2 ft of snow I was SO tempted to try to get some off the roof...I was warned by our friend Dawson to leave it alone that it would slide off our metal roof in time. It did...In huge piles that I probably would have been buried under if I'd attempted snow removal myself. Are you still snowed under back east? I'm still in Phx now, but long for the NW and the fresh,clean air. Be well! xx-c

John Poole said...

Cassie ~ Helloooo back at you, cousin! Glad to hear from you, and glad you got a kick out of this post. We still have snow all around, but much of it has melted at this point. I think spring is right around the corner!

Two feet of snow? Wow! That's a lot for November! I don't know if your metal roof has snow guards just above the eaves, but sounds like you might benefit from them, if you don't. So the snow doesn't come crashing down and bury you in an avalanche!

Hope all is well by you and Patrick and Hootie and BRD. Will stop by your blog and check out what you've guys have been up to!

Best always, Cuz John