Metal roofing and siding

[KinAlberta]

I'm after general thoughts, knowledge and experiences, etc on metal roofing and siding on rural cabins, cottages, boathouses, sheds, garages, barns, etc. Basically all things metal siding and roofing. (Making such discussions open ended always leads me to learn things I never would have thought of and so never questioned.)

Specifically, we have a lake property with some old buildings on blocks and/or skids, some with wood floors but a 22x24 garage on blocks with just a dirt floor. Four buildings have metal roofs (two built new with heavy metal roofing right over the rafters without sheathing, and two buildings with new metal over old shingles and sheathing). Others that now need new roofing and others that need work on their siding.

So some buildings need some levelling (0.5"- at most 1.5"" at a corner). Could that work telegraph up to the metal roofing and stretch the holes or would wood flex?

Is metal siding worth the expense? Some of our buildings are just stained or painted plywood. Upwards of 40+ years with just one interim painting or staining but now again needing some cosmetic treatment.

Issues?
Eg Is the fireproofing propaganda just that, propaganda? In a forest fire with trees nearby do metal building just light up like any other building? (Assuming one seals the soffits and runs metal to the ground on sheds, boathouses, etc. so embers don't just suck into attics, will metal siding actually help a lot in a nearby forest fire or will the screws and siding just heat up and ignite the wood behind them.

Since the buildings are on blocks, I could reinforce the floor beams, or I could laminate another layer of siding on a couple buildings (eg three walls of our boathouse) to improve their rigidity. However does metal siding by itself significantly reinforce the wall strength of a squared up building so it is less likely to bend or dip anywhere along it's length? (Yes, ideally oversized foundation beans would do that but since a taller beam is far better than a wider beam, my thinking is that a laminated wall (say two overlapping layers of plywood without any door openings must be incredibly rigid (like a cardboard box) thus overcoming any weaknesses from average sized beams. (Corners would also need reinforcing though.)...


Anyway, random thoughts here, and more random thoughts welcome.

[Redfrog]

I just a reroof on my house. Metal over shingles. I used strapping over existing shingles.

I was going to go with shingles again until I spoke with John at the Holden Hutterite colony. Google it.
They make the panels and will install as well. I did my installation but these guys know what they are doing. They also have all the extras you need. Any color and the price is a good surprise.

[ChickakooKookoo]

I happen to run the metal distributor for prepainted metal products in Edmonton, I can offer some guidance...

As far as price goes, if you're paying to have them installed prepainted metal will typically run you 2.5 to 3x the expense of shingles. If you're doing it yourself, just depends on what kind of bargain hunter you are. Some companies will have leftovers from bigger jobs and if you're not picky on color, they sell them cheap. Also, some guys run custom panels but they may have too much stock in a color so they'll give you a deal on this brown or that red... Really no rule there, you just need to call around to see what you can find. And yeah, there's about 15 Hutterite colonies in Alberta that make this stuff, usually a good place to find a bargain.

Lifetime wise you're going to see about 100 years before the metal will rust through, but metal still fades, chalks, etc. It needs to be cleaned once a year if you want the color to last but you'll still be repainting it 30 or 40 years down the line.

Fire resistance wise, the metal is rated to "ASTM E84" fuel contribution zero. Basically means that the metal won't burn and contribute to the fire but how it affects what it's attached to is out of my scope. My personal opinion though - If the fire is close enough to heat the screws enough to start the wood on fire, that's probably your last concern. If the fires that close the building is going to burn down, irrelevant of the roofing type.

I can't offer any help on the install side of things as we're a metal distributor, I have no experience there. If you have any questions on the metal itself PM me and we can talk on the phone.

[HighlandHeart]

While we are talking about metal roofs, how often do I need to check the bolts? The fellow trying to sell me a new roof tried to make it sound like the exposed fasteners were a problem.

[35 whelen]

I picked up a metal package did 14 x 45 cabin and had tin left over everything was there screws flashing foam that goes underneath for 500 bucks picked up one of the best deals I've ever gotten for anything check out some of those big tin places

Sent from my SM-G930W8 using Tapatalk

[ChickakooKookoo]

Originally Posted by HighlandHeart

While we are talking about metal roofs, how often do I need to check the bolts? The fellow trying to sell me a new roof tried to make it sound like the exposed fasteners were a problem.

Not sure but the MRA (https://www.metalroofing.com/) is a good source of info for all things metal roofing.

Also, if you're interested in understanding how the color you choose affects your monthly power/gas bill - http://coolmetalroofing.org/

[coastalhunter]

Typically, 5 years is the exposed fastener lifespan. Environment dependent obviously. Standing seam or snaplock is the way to go, 95% of the fasteners are hidden this way.

[KegRiver]

I have installed metal roofing on some of my own buildings and for others.

My trapline cabin, one garage of mine, on one property I own, a shed in my yard, my second house, two machine shops and I forget what all.

Some of the roofs are over thirty years on, no issues. I don't know anyone, including myself who washes or checks screws. All exposed screws.
No issues, yet.

About fire, all I know for sure is a metal roof sheds sparks like a ducks back sheds water. And it don't do much good when the walls catch fire.

We plan on putting metal on our present home. I will never buy another shingle. I've installed thousands of them, none that lasted for the indicated life advertised.

Asphalt burns hot.

[Travis44]

Strapping and metal is the way to go!

[KinAlberta]

When it’s used as cladding on unheated sheds, garages, boathouses, etc does it have to be strapped? Would products like tarpaper, gritty roofing membrane etc make any differences in terms of preventing or creating trapped moisture problems?

Running firring to me isn’t desireable because it will allow the panels to get dented. I’d rather have them flat to the sheathing.


Also, I have buildings on blocks (Eg 16x22 boathouse on blocks on sand/muck/gravel...) so I’m planning to beef up the beams where I can access them but am also considering another layer of sheathing to essentially turn the walls into beams to stiffen them and reduce the risk of sag, so the metal won’t be at risk of damage from movement.

[skidderman]

Originally Posted by KinAlberta

When it’s used as cladding on unheated sheds, garages, boathouses, etc does it have to be strapped? Would products like tarpaper, gritty roofing membrane etc make any differences in terms of preventing or creating trapped moisture problems?

Running firring to me isn’t desireable because it will allow the panels to get dented. I’d rather have them flat to the sheathing.


Also, I have buildings on blocks (Eg 16x22 boathouse on blocks on sand/muck/gravel...) so I’m planning to beef up the beams where I can access them but am also considering another layer of sheathing to essentially turn the walls into beams to stiffen them and reduce the risk of sag, so the metal won’t be at risk of damage from movement.

I believe the tin needs to breath. If you attach directly am pretty sure you will have condensation problems. I'm no expert though.

[KinAlberta]

My thinking here is that I can maybe double the sheathing (overlapping the old for a laminated beam effect) and I’ll then also have enough thickness to hold the screws without the 1x4 strapping.

A mistake I this past year is that I repaired one building using some PT lumber on the walls with the plan to cover it with metal siding. Now I’m thinking that the pressure treatment might corrode the panels and the screws.

Any thoughts/experience on all this?


Oh, and regarding the screw washers, I’ve heard that they should last about 20 years. We have both types of roofs. The standing seam are many decades old. Should have gone with it on the two recent jobs we had done. :-(

[fishtank]

Originally Posted by coastalhunter

Typically, 5 years is the exposed fastener lifespan. Environment dependent obviously. Standing seam or snaplock is the way to go, 95% of the fasteners are hidden this way.

do they make any stainless steel bolt/washer or fastner ?? would be a pita to change them after 4 year as mention that their lifespan..

[KinAlberta]

How poor quality washers can cause corrosion on metal roofs | Architecture And Design
https://www.architectureanddesign.co...orrosion-on-me

neoprene washer | Ask The Experts Forum | Metal Roofing Alliance
Nate Libbey
2/2/2009
A few things about the washers: Some years ago, panels were installed using nails or screws with rubber washers. These washers were directly exposed to the sun, which made them dry up and lose they're seal. The screws mostly used now are much more advanced. Some of them are different, but the below description fits most of them: Commonly hex head washers, The screw is galvanized, then painted to match the panels. It has a metal umbrella washer with a neoprene rubber seal under it. The metal washer covers the neoprene rubber seal almost completely, leaving only a thin edge exposed. This protects the rubber from the UV rays of the sun, greatly prolonging its life span. Even then, after 15-20 years its not a bad idea to have someone go up on the roof and inspect the fasteners. Replace any that have problems at that time. These type of screws have been very successful for some years now. The only time I've seen problems with them is when they they were put in too tight, too loose, or crooked. (Make sure to set the torque on the power drill.) Another thing I’ve seen is when the screws were put into green lumber that wasn’t properly cured. They loosened and had to be retightened.


https://www.metalroofing.com/spirit/...oprene-washer/

Exposed Fastener Metal Roof: Pros/Cons? | Fine Homebuilding | Breaktime
http://forums.finehomebuilding.com/b...-roof-proscons


Some newer roofing screw design - “ultimate screw”

http://atlasfasteners.com/Atlas-Lite...mate_Flyer.pdf

.

[Battle Rat]

The Fire Smart program is not propaganda.
A structure in direct line of a forest fire will be lost regardless of the material.
Embers blowing from a fire a mile away will ignite a flammable roofed structure much easier.
Metal is better than asphalt and asphalt is better than wood shakes.
There a pics of houses at Ft Mac and Slave Lake left standing while those around burnt down.
Grass left to grow up to the side of a structure with vinyl or wood siding greatly increases the chance of ignition.

[KinAlberta]

Yeah the firesmart information is interesting. The propaganda I’m talking about is the metal roofing/cladding promotional information.

[220 Swift]

I think the barn at home was built in the late 40s. Galvanized Tin roof with nails and lead washers.

We were up there about 20 years ago and hammered in some of the old nails that wiggled up and probably put some screws in. If they only built them like this now adays.

[JimW55]

I wouldn’t go with metal siding I would go with vynil, aluminum roof yes and shingles weigh more than aluminum.

[crosman177]

If you’re in Calgary area check out Jay’s metals products. High quality with the best prices and service around.


www.jaysmetal.net

[Battle Rat]

Originally Posted by KinAlberta

Yeah the firesmart information is interesting. The propaganda I’m talking about is the metal roofing/cladding promotional information.

Think of it like where blowing snow would gather on a roof valley or in a corner under a deck.
Embers would gather in those same areas and in the eaves trough so keep the leaves cleaned out.
If the cabin is a simple roof design, then the threat would not be as bad.

[KinAlberta]

From what I’ve read over the years is that the embers also get sucked into the attic so some of the problem is with soffit and venting. (Seems to me that they wouldn’t ignite the attic floor due to insulation, but could start say, the gable end framing on fire.)

Of course wood decks, plastic garden sheds with plastic cans full of lawnmower gas, etc don’t help.



There’s the obvious too:

Why do houses burn but trees remain? Photos from California wildfires reveal lessons for B.C.


Retired U.S. Forest Service scientist examines wildfire footage to find ways to reduce burn risk

Clare Hennig · CBC News · Posted: Nov 14, 2018

“"Our perception is that this wall of fire comes through and destroys everything, and yet what I'm seeing is that there couldn't have been a wall of fire," Cohen told Stephen Quinn, the host of CBC's The Early Edition.

"The thing that would have carried the wall of fire is still there: The trees are still there and the structures are destroyed."

...

“Removing clutter around homes that could become combustible is crucial, he said, and making sure there is nothing touching a structure that could ignite it.

"We make sure that we have no debris on the structure. We make sure that nothing can burn ... within the first metre to metre-and-a-half [of the house]," he said. “

https://www.cbc.ca/news/canada/briti...-b-c-1.4905324

Blizzard of embers sparked fires that burned Fort McMurray homes last year | CBC News

May 14, 2017

Alan Westhaver says the embers ignited combustible material such as dry grass, leaves, pine needles, fences, patio decks, wood piles, evergreens and ornamental shrubs that were too close to homes in the northern Alberta city.

The smaller blazes set homes on fire and flames then crept to nearby houses in the closely built subdivisions.


"Wind-driven embers from the forest fire likely caused the majority of home ignitions near the urban perimeter which, in turn, likely triggered the massive urban conflagration and losses that followed."

The wildfire forced more than 80,000 people from the area and destroyed more than 2,400 buildings. Insured losses are estimated at about $4 billion.

The report says few homes caught fire due to direct contact with the flames or heat from the burning forest.

"No, this fire was not, at least initially, an insurmountable force that rolled into, and over, an entire community like a smashing tidal wave," said Westhaver.

"Primarily, it was millions of raisin-sized firebrands searching for places to carry on with combustion, and succeeding all too often."

https://www.cbc.ca/news/canada/edmon...rray-1.4114748

http://disastersafety.org/wp-content...mbers_IBHS.pdf





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[Big Grey Wolf]

Proper procedure when installing metal roof is to not over tighten the screws/ rubber washer, set drill torque low enough so they are not flattened like a pancake. They are then good for 50 years.

[KinAlberta]

You said rubber washer. Or did you mean one of the newer materials?

[1899b]

Growing up my friends parents house had a metal roof. Darn snow would slide off the roof at the most inopprortune times and cover the sidewalks..

[dicknormal]

I've used metal for the inside walls and ceilings of both my attached and detached garages. A bit more expensive than drywall but far less labour involved. Install with no mudding, sanding and painting. We use a plasma cutter, mig tig and arc welders with less fear of sparks causing fires.

[bat119]

Originally Posted by Big Grey Wolf

Proper procedure when installing metal roof is to not over tighten the screws/ rubber washer, set drill torque low enough so they are not flattened like a pancake. They are then good for 50 years.

This ^^^^

Most important part of installing metal roofing material

[KinAlberta]

Over tightening isn’t such an issue with standing seam.

[stubblejumper01]

Originally Posted by dicknormal

I've used metal for the inside walls and ceilings of both my attached and detached garages. A bit more expensive than drywall but far less labour involved. Install with no mudding, sanding and painting. We use a plasma cutter, mig tig and arc welders with less fear of sparks causing fires.

I did the same and love it. Magnets work anywhere, if you're reefing on something that breaks loose and goes flying, no wall damage
I didn't want the extra work it would take to do the drywall. Never even compared the cost

[KinAlberta]

Putting up drywall in a garage makes little sense to me. Can’t nail and screw on shelves etc where they are needed without extra work. The moisture levels are all over the place too.

[KinAlberta]

I’ve realised how important bottom-up thinking is before I actually start putting metal siding on our old plywood sheathed outbuildings (all on blocks and/or beams).


One, square up the old buildings and increase their resistance to sagging
- so just level them up with some jacks and then sister on some 2x__s to existing beams or add an extra beam or two. (This will help but not stop building movement and I’m guessing will still allow metal cladding to bend, bow or even buckle.)

Two: give the existing old framed walls more beam-like strengthen
- “laminate” on another layer of sheathing maybe with 2x10 or 12s top and bottom to create a bit of an I-beam effect or
- put diagonal bracing on the exterior walls then fill in with horizontal furring to attach the siding

Three, fireproof by add flashing that would wrap under the building and then add some dirt-cheap but fireproof skirting to the bottoms of the buildings so a simple grass fire can’t light up the structure. (Gravel perimeters would only be good for a few years without regular maintenance which just isn’t going to happen out there.). Skirting needs to allow access to re-level the buildings every couple decades.

Four, where there’s no furring and just flat plywood sheathing add some sort of spacer material between the wood and the metal cladding to allow it to breathe a bit.