Metal Roof .. OSB Problems

My metal roof is eight years old and while cleaning the chimney I noticed some screws backed out and others loose. While replacing them I at first thought the roofers over tightened them .. but as I snugged them up and put a good screw in on either side .. I noticed gaps in the pressure as they went in .. which I take for hidden blank spaces in the layers of OSB or patches of bad chips. While placing surrounding screws I felt bad places right and left and up and down. I just kept probing until I got the re-enforcement necessary.

We are getting days of 60 mph winds and higher. A loose roof is the last thing I need. I started trimming my shade trees with thin spots in the middle after having some blow over. I am putting posts in on the West side and building wind breaks for the trees like I have for the livestock. So far, that has worked and when I tell nursery people what I have done .. they get excited .. say they are going to suggest that also.

We are about to put a new metal roof on our home, any suggestions or advise?

Hi Jennifer,

We love our metal roof .. let me say that right up front .. the sound of rain hitting it at night just makes us smile .. but we live in the high desert.

Having just "hit the problem" I'm not sure what I'm finding but I have accurately described the symptoms. Are you putting the roof on or is a contractor? What is your underlayment? Are you putting a new deck material down or going over old .. check on its integrity.

I have personally built a chicken coop and four other sheds and they are newer but are not showing the same problems .. a high wind hit one shed and tore the 90% finished roof into pieces .. it faced into a ? .. sixty mph storm and the leading edge was what I was working on and had not gotten it all screwed down.

If you don't have a new impact drill .. I highly recommend them. I have a DeWalt 18v and it has one battery and it recharges fast .. or you can get two. It has power that you never saw in the old lower voltage non impact drills. They may / probably have something newer and better out now.

If you put the rubber strip on the bottom edge .. that fills the open ends where the ridges are .. make sure it is screwed through with the holding screws. It will have it's own adhesive and it is a joke. My contractor did not read the directions and it is all coming off.

Hope this helps .. ask more questions if you want. Nice meeting you.

Thank you Dusty. 

A young man from town who works for his father, putting up metal buildings, is doing the work for us.  Seems a nice young man. 

I will read what you wrote to my husband and parts of it to my roofer.  Thanks so much.  After I talk it over I might have more questions. 

What part of the country are you in?

my main reason for never using a metal roof....they  tend to leak at the screws..

as for a windbreak..wonderful idea..we are planting more and more all the time here..my son put in a newer home next to us a few years back and he has a horrible problem with wind as his house sits up high..i plan to plant some white pines on the NW side of his house on our property line in the next few weeks, (while we have wet)..as there are thousands of babies in his field..(which we are letting go to forest)

Brenda, what kind of screws are you using? We use the ones with a lead washer which makes them leak proof unless they become loose .. plus .. on a good year we only get seven inches of rain .. high desert South Central Idaho .. Oregon Trail.

I am about to put up wind breaks for my front pasture with a small roof overhang .. 3 or 4 feet. I have one old witch so I must provide an escape hatch for the other horses to get out of her way and where she can not trap them in there and kick the heck out of them.

While on this subject .. always feed the pecking order and ride the pecking order. If you are not "on" the meanest horse you have .. you can get hurt bad .. learn how to watch and have fast fenders .. swing your legs up out of harms way .. don't go to sleep .. watch the ears .. doctor lesser animals on the near side to the lead pecking order or don't go in. That way the lesser horse can't run over you .. will run away from you because the lead pecking order will drive them away from you.

I use treated square six inch posts with a  three feet bury no cement .. tamp dirt in. Cheap stuff they will chew on. What are your tricks?

We've used metal roofs on all kinds of buildings, including 3 homes that we built, for nearly 30 years (the ribbed/ridged kind installed with screws - not standing seam).  We've always used the roofing screws with rubber washers under the heads.  The screws are placed on the "ridges" of the steel only and into 2x4 purlins.  The 2x4's are laid flat, not on edge, about every 2 feet.  There is no other roof decking under the steel, so when walking on this type of roof it's best to step where the purlins are, although not crucial (depends on how much you weigh).  On insulated buildings, we do install Tyvek under the purlins in case there is any condensation from outside air on the underside of the roof steel.  If there is ever any moisture, this would keep it from the insulation and would let it run down and out the vented soffits.  The overlaps of the steel sheets are caulked as you go.

My roof is going on as I type this.  I miss my camera.  It is my roofer and his two younger brothers.  They all work for their dad building metal buildings as a weekday job.  Oldest brother 27

Walk wrote:
We've used metal roofs on all kinds of buildings, including 3 homes that we built, for nearly 30 years (the ribbed/ridged kind installed with screws - not standing seam).  We've always used the roofing screws with rubber washers under the heads.  The screws are placed on the "ridges" of the steel only and into 2x4 purlins.  The 2x4's are laid flat, not on edge, about every 2 feet.  There is no other roof decking under the steel, so when walking on this type of roof it's best to step where the purlins are, although not crucial (depends on how much you weigh).  On insulated buildings, we do install Tyvek under the purlins in case there is any condensation from outside air on the underside of the roof steel.  If there is ever any moisture, this would keep it from the insulation and would let it run down and out the vented soffits.  The overlaps of the steel sheets are caulked as you go.

I worked with a contractor for a while and we installed metal roofs on a couple buildings during that time. We did just like you do except the part about using the Tyveck. Our cases were a just a little different in that the metal roofing was installed over an existing shingled roofs. We also installed 2X purlins flat every 2 foot, but we used 2x3s since the existing roof provides good support.

We found and marked the rafters and used long screws (4" IIRC) to fasten the purlins right down tight. I wouldn't feel comfortable trying to fasten to the roof sheathing without hitting a rafter below it. We cut and placed 1.5" foam insulation between the purlins and held it in place by using the next purlin to hold it tight against the one below it as we went up the roof putting them all on.

This would be the way I would do a roof for my own home, if I couldn't build an underground house. Now, I just need to get some land...

Will

I wouldn't trust panels screwed to measly 7/16" OSB in a high wind area.  Espescially when the installers probably used screws that were too short.  If you don't use purlins as others suggested, I would use 3/4" plywood for roof sheathing.  There is the sticker shock at the lumber yard, but for a reasonable-sized home it only adds a few hundred dollars.  We are talking about the roof over your head. 

I've go the six posts up for a 20x6 loafing shed .. my two Sun Valley horses are here for the winter and my two are in their pens while I'm working on the shed in their pasture. The Friesian .. free .. my grand daughter's .. waited until it rained and stomped her muddy huge feet all over my wood stack and scattered it. Nancy and I were out there having to clean each board before using them.

For the roof we are hanging 2x6 in metal hangers and will screw the metal siding into them .. we are skipping the OSB on the walls and the roof all together. Wind can get under these roofs .. unlike a house .. and I am tired of taking chances.