I have put in my time studying the gutter guard market and I think I've found
the best products.

The very strongest and best performing require a metal sheet to be placed
under the edge of the roofing material. In most situations this is not a big
problem but our metal roof is nailed into wood instead of screwed into metal.
So, I can't just back out the screws and reseat them.

Is it possible to pry up the edge of our roof enough to slide the guards underneath
without damage?

Where would you pry? Should I replace the fasteners at the edge with something
else or try to reseat the nails?

Our other option is to use an inferior product from the same company which we
can screw into the fascia on the upslope side. It might work well enough but I
am trying to setup my grandmother's house so she won't have to worry about
it ever again as I might be moving away soon.

 

How old is the roof? most metal roofs today are screwed down.

 

It is about 18-20 years old. The shop, built by Morton on the same property,
used self-tapping screws into its metal frame, but the house, with a wooden
frame, has its roof nailed into place.

 

I'm afraid if you loosen the nails they might not go back in securely. You could remove the nails at the bottom and replace them with screws.

 

That is one thought I had. Since it is going into wood, I need some kind of wood screw, with a
diameter greater than the nails, and a gasket under the head? Do they make these?

If so, how should I pry out the existing nails without damaging the panels?

 

Carefully pry out the old nails. May need to use a block of wood to pry against.
They sell special nails with neoprene washers for metal roofs. You can probably get them the same color as the roof. I don't remember the exact lengths but they mostly come in two sizes; short and long. Assuming your nails were driven thru the high portion of the roof, you'd want the longer ones.

 

Ive tried every gutter material made, plastic, metal, expanded etc and the only one that I would recommend are the foam batts.

Many brands now but do not require any modifications and I;m on year 8 and they are still performing great.

 

Never found a good use for wood screws. They are passable for joining two pieces of wood together and that is about it. Even then there are better solutions. Almost any screw will work in wood. What you need is a self-drilling sheet metal screw with neoprene washer.

 

marksr: You think if I put new nails into the same old nail holes that they will be secure enough? What do you think about ray2047's suggestion of using metal screws into the wood?

Marq1: I've surveyed the gutter guard market quite extensively. All of my research points to a dense mesh product from a California company. I'm not sure I am supposed to mention brands but I guess the moderator can edit it out if against the rules. The company is called Gutterglove and they got the Consumer Reports best buy in this category for 2015. One of the problems with the foam is that stuff can lay on top of the foam. It can also fill in the voids in the foam on the top over time. Another is that the foam tends to provide an environment for fungus, algae, etc to grow, which will restrict water flow, and could even be a health hazard. Many complain of foam breaking down in a few years as well. Mesh products get the most consistent high reviews and the product by Gutterglove seems to be the best because it is just the right density of mesh. It is not so tight as to restrict airflow and promote algae growth but it is tight enough to block nearly all manner of debris. Plus, if you install it at a decent slope, usually the slope of the roof is adequate, gravity helps the winds to blow stuff off of its surface. You can find Youtube videos of pretty much all gutter guard types, mesh or non-mesh, and not installed with a fair degree of slope, caked and covered with debris. Of course, we would happen to have some of the worst types of trees for generating clogging debris surrounding my grandmother's house. Oak's are some of the worst because of the catkins. There are many other types of trees that are not so much of a problem.

 

The screw I posted is for metal roofing. Metal doesn't describe what the threads or intended for. It is just a description of a common use like carriage bolts can be used on things other than carriages but are still called carriage bolts.

 

The screw Ray posted a pic of is the type of screw I meant. I think those screws going into the old nail hole will be ok but you really won't know until you screw a few in. If they don't screw tight you'd need to install another one next to it. If it comes to that, the old holes can either be plugged with a screw or filled with caulking.

 

Ok, thanks guys, I guess I'll just have to get some long screws and give it a try.

I just always assumed there was a significant difference between wood and metal screws for some reason. The threads on metal screws I've always seen are much tighter or denser. Maybe this is because it needs to grab the edges of metal which can be thin rather than being anchored in a somewhat pliable material like wood.
It seems to me it would be easier to "strip" (for lack of a better word) a hole in wood with the denser threads.

I have sunk a few metal screws into wood in the past on our barn and they seemed to hold OK.

 

These screws are tailor made for screwing down metal roofs. Besides being stocked on the aisle where all the nails/screws are, they are often found next to where the roof panels are.

 

Yep. I have two valleys that provide a concentrated amount of the gritt off the shingles, I had to swap out two inside corners of material at about 5 years.

Butt after 8 years of leaves and everything else that comes down the roof they dont look too bad!

 

That looks great Marq1, you must not have too many of the problem type of trees surrounding
your house. I have never found any pics of foam a few years old that looked that clean! I'm sure
our oak trees would clog it up, catkins are one of the worst things you can have for gutter guards
that are common. There are a few trees that are worse but they are not so widespread.