Metal roofing-How to cut it?

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Almost half of my pole buildings roof(metal) was ripped off in the high winds we had the past few days.The building is insured for replacement only since it is not complete yet.Basically I am headed for the lumberyard now for some galvanized metal roofing(channel type)I am going to replace the whole roof which is about 1300 sq ft.I would apreciate any tips anyone has for laying this stuff down(first time with metal)I have read in past threads about making sure you use screws with the rubber gaskets instead of nails.How do you cut this stuff without having a nasty looking cut line.?also should I lay tar paper down before applying the roofing.I will be doing this by myself and am hoping the winds die down and maybe temps could rise a bit.Any and all tips are welcome.Thanks Dave (Central WI)

-- Dave (duckthis1@mybogusemail.com), March 11, 2002

Answers

Take an old carbide blade from your ripsaw in put it in backwards. Be sure to wear safety goggles and leather gloves because the sparks really fly. Clamp the panels down good and tight on your saw horses and use a no.2 pencil to mark your cut lines. I did a 24 x 24 pole barn this way.

-- ron bulinda (rvbulinda@yahoo.com), March 11, 2002.

I wouldnt use a carbide blade,, boy,, talk about shrapnel,, but they do make abrasive blades that work just fine

-- Stan (sopal@net-port.com), March 11, 2002.

Dave,

I recently replaced some 5V metal roofing and used my 7 1/2" circular saw with abrasive blades to cut the material. The abrasive blades worked great, but didn't last too long. The abrasive blades wear out as they go through the metal. However, they cut through the material very easily and leave a fairly clean edge. In a few places I had to clean up with tin snips and a file, but overall no problem. Lots of sparks, but that was expected. Wouldn't suggest cutting inside a barn or around any dry straw or kindling. I also used the abrasive blades to cut through some one-inch pipe. It was a cinch. When I cut the roofing material, I just drew a line on the tin with a permanent marking pen and then cut it like it was a piece of wood, except I did wear ear plugs. Sometimes I'd just use a scratch awl and mark the line and one time even used a pencil -- kinda depended what I had within reach. I've even been known to mark a piece of metal with an 8d nail. I'd suggest you buy a couple of abrasive blades and give them a try. They aren't very expensive. I think I paid less than $5.00 for each of mine. Hope this helps.

-- Ed (ecpubs@lynchburg.net), March 11, 2002.


As to tar paper are you wanting to lay something in the overlap areas to help seal better? Some peole use a silicon caulk to add sealing but most don't. Getting the screws to start into the tin can be a hassle, so don't start slow but fast to get the screws to catch. A chalk line to line up where your screws are going is also a nice plus, s is a good pair of sun glasses (due to reflection off the tin). SOme people say only put the screws on the top of ridges, some people put them wherever, I like the top of ridges but be careful not to tighten too tight or you will dimple your ridges, more cosmetic than functional.

-- BC (desertdweller44@yahoo.com), March 11, 2002.

I use the abrasive blades, but I'm trying to remember the number of cuts I get on them. Seems to me it was about 12 sheets? In that neighborhood, anyway. So having two blades is a good idea. Nothing like getting down to one sheet to cut and the blade is gone! They make a fairly nice cut, too. I usually try and hide the cut under the next sheet of steel or else up next to the ridge cap where it will slide underneath. It will be a sharp edge, so handle the cut sheets with gloves.

-- Jennifer L. (Northern NYS) (jlance@nospammail.com), March 11, 2002.


1. A regular wore-out wood saw blade, _backwards_ in your electric circle saw will make a lot of sparks, noise, and do the job. I would try to order the tin pre-cut to length - MUCH easier. You can get it to the inch, what you need.

2. Tar paper - well, is this a full sub-roof, or just the beams across that you nail into? Are you going to heat this or work in it, or is it just storage?

If you plan to ever heat it, it's gonna drip water on you & the tools. You need a liner up there. If this is just beams, there are much better liners than just tar paper available. Ask at the lumber yard. If it is a full sub-roof, then you can use tar paper, _but_ you need to roll a layer of cardboard material over that! Tar paper should not be in direct contact with galvanized metal - bad reactions.

--->Paul

-- paul (ramblerplm@hotmail.com), March 11, 2002.


Some good advice above, BUT, spend a hundred dollars and buy some electric shears or "nibblers". You will LOVE them and all your neighbors will want to rent or borrow them after you are through with them, so they'll more than pay for themselves! They also save your ears, lessen the chance of fire from sparks and leave a very clean edge. They work in valleys as well as ripping and crosscutting or even circles if you wish.

There are many different kinds of metal, each has a different method of installation. Get the manufactures recomendations for the specific metal you purchase. Most has a drip edge that must be properly installed to avoid wicking leaks. Some metal is designed to be screwed through the ridges, some on the flats. Get the proper screwing pattern from the manufacturer!

If your roof is skip sheeted, you don't tarpaper. If it is solidly decked, by all means use good quality roofing felt. By all means measure from one end and snap chalk lines. Metal tends to "grow" or "shrink" as you go along which will leave you with an odd looking piece at the end. If you always check your measurements you can adjust as you go.

Do buy the nibblers, you won't regret it and you won't ruin your saw.

-- Tis I (really_tis_i@yahoo.com), March 11, 2002.


"Hoping the winds die down".

That's a necessary precondition - not a "it'd be nice". You DON'T want to be up on a roof fighting a piece of roofing iron that the wind has got hold of - that's a good way to lose fingers or lives. In fact, if it gets to that, decide in advance to just let the iron go - throw or push it if necessary to get it clear of you - cheaper than being cut by it. Handle the iron so you keep it low - that way if you do get a gust the wind shouldn't catch it.

-- Don Armstrong (darmst@yahoo.com.au), March 11, 2002.


Yes, the "nibbler" works best. We tried all the above but didn't like the results, etc. Milwaukee makes one. Catalog # 6850. Sears special ordered it for us & I think the price was around $130.00.

-- Jenny Malone (doggarden@msn.com), March 11, 2002.

I just cut a bunch yesterday with my old B&D circular saw fitted with a special metal cutting blade. Of course I used safety goggles and heavy gloves. Was loud, lots of sparks, etc.; but worked great, even cutting a 10' length of corrugated siding at an angle. But Dubya my dog wouldn't come near me the rest of the day after that.

-- SteveD(TX) (smdann@swbell.net), March 11, 2002.


Hello Dave,

There is a "special blade" for cutting sheet metal. It is triangular and cost about $6.00. If you do not want to do it that way, you can turn your regular saw blade backwards and use it, providing it is not carbide since the tips are welded on and could break off. Another type of blade is an abrasive blade like some cut off saws have only bigger that would fit you circular saw.

Sincerely,

Ernest

-- http://communities.msn.com/livingoffthelandintheozarks (espresso42@hotmail.com), March 11, 2002.


Wait til the wind dies and don't do it by yourself. Hubby ignored both and was nearly decapitated as the piece he had just thrown up onto the roof came rumbling down said roof just as his head topped the eave line coming up the ladder. A quick duck and .... whoosh - the piece sailed overhead at a decent clip (which is what he almost got). Yes, this is the same hubby that cut off a few pieces of his left hand last year using a Skil saw unprofessionally. Can't take that boy anywhere.

-- Soni (thomkilroy@hotmail.com), March 11, 2002.

I agree with Paul but with one ammendment. You don't need a carbide blade but I would suggest a fine toothed wood blade installed on the saw backwards. You get a smoother cut with a finer toothed blade. Safety glasses and gloves are a necessity---schrapnel sometimes.

Also ditto the advice to avoid handling the tin in wind. Thats a recipe for disaster.

-- john (natlivent@pcpros.net), March 11, 2002.


Thanks everybody,I definately will wait for the wind to die down and am going to price a nibbler tomorow.Thanks Dave

-- Dave (duckthis1@mybogusemail.com), March 11, 2002.

Dave, Also consider predrilling the metal sheets on the ground. Do this by determining where you want the screws and drilling many sheets stacked together. You will like the straight screw rows and is easier to screw down when on the roof.

-- Tom (tomdarsavy@cs.com), March 12, 2002.


Tom, You are a hell of a human. I'm putting my steel roof up this weekend from 84-lumber "Metal Sales" steel roofing. That's a great idea to pre-drill. I have built the garage/barn pole style with just the girts no flat panels. I WAS LEARY of the screws self starting them selfs.

-- JAMES CODY (BALOOGABILL@YAHOO.COM), March 12, 2002.

Drill the holes small - tiny actually. Let the screw get it's bite.

And in this case instead of measure twice, I would say measure _many_ times, drill once - any mistakes will ruin a pile of tin! :)

--->Paul

-- paul (ramblerplm@hotmail.com), March 12, 2002.


I use a shear that looks like a big paper cutter. Take two people to do it right, one to hold the metal straight and one to pull the handle down. It is fairly heavy so it does not move much. I use the elec cutters to cut around items and to cut length wise. In a wind roll them up like a cigar and they are easy to carry and then slap in place quickly. But you can get metal made to the size you need but almost any metal place so you don't have to cut. In wood or metal I have the best luck with the point that taps and drills there own holes but you are better off with a special driver drill to put them in with. 2 1/2" wood thread for wood and 1 to 2 in metal studs or pipe. Have put up several metal buildings, metal and wood frame and have learned the hard way. Regards Bill

-- Bill Porter (porboy298@yahoo.com), March 12, 2002.

i put on a roof last summer bought all pre cut. most mfg. will ship upto 16 ft long

-- nick (ray_@sympatic.ca), March 14, 2002.

16'??? They must use more tin around here, everybody stocks up to 16 or 20', they will custom deliver anything from 1" to 40' around here. (Yea, advertising, like anyone would order 1" pieces....:) Really the way to go, no splicing seams, and less cutting.

--->Paul

-- paul (ramblerplm@hotmail.com), March 15, 2002.


Rent a 14" gas powered demo saw. You can cut 10 at a time. Be sure the cut edge is not exposed to weather. Cut edge under ridge, factory edge @ eve. Be sure to install eve trim, and overhang roofing one inch into gutter. If your installing roof over a solid substrate definately use 30# felt. If your installing over open purlins use a condinsate blanket.

-- Ron (Dawn_Ward@email.msn.com), April 02, 2002.

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