Do foam inserts for gutter covers work? As an engineer my opinion is that the best application for foam is for packing materials or a great quality mattress but not as a gutter guard.
Can you pretend that you are a blossom? Along with many of your blossom friends you drop into a gutter that has a foam insert. You are a beautiful blossom and so are your buddies, but your life as a blossom is coming to an end. Why?
Either your time has expired on the tree or you've been knocked off by a few hard hitting rain drops--ouch. The reality is that you have settled on the top of a foam insert--a hard cushion. Being light in weight you really don't need a cushion, do you?
Now what's in store for you? Are you going to be blown away? Or will you be somehow dislodged and drop to earth? Or will a bird, squirrel, or raccoon step on you?
Let's remember that foam makes and excellent mattress. So what happens with the wind? Will you be lifted from your comfortable mattress and be air born again? Think for a moment, how might this occur? You are lying flat on this cushion right on top of the gutter. Any wind whipping down the roof will simply overshoot the gutter and go off into space. Wind whipping toward the gutters will simply knock you into the rear portion of the gutter. Wind whipping along the gutter will simply blow you toward the other end of the gutter--maybe a couple of your buddies will get air born, but I'm afraid you're stuck there in the gutter. And if you've been wetted by a few rain drops there's no fluff in you to sail away--a soggy mess you are. And after you dry, you've been flattened on the comfortable mattress. What comes next? Answer: you're going to deteriorate into tiny pieces and accumulate on that comfortable mattress. Eventually enough of your buddies will join you and your accumulated mass will simply close all openings and holes in that foam preventing any rain water to get into the gutter.
The engineer suggests that you forget about foam inserts. Do you think leaves in the Fall would be much different? Don't think so. It will simply be more of you accumulating quicker.
The engineer will suggest that the answer to keeping leaves and blossoms from getting into the gutter is a solid top gutter cover.
To find one such type, Google "Niagara gutter guards". Again, if you're a blossom you'll fall onto the top of the gutter guard|You'll drop onto the top of the gutter cover if you're a blossom]. If you're dry, a slight bit of wind will blow you away--no comfortable mattress there for you. Yet if you're soggy and wet, you will stay stuck on top of the gutter guard. However, the rain water will gently tug on you as it passes you on its journey into the gutter. In fact over the course of several minutes it will gently wash you along with it so that you will hug the contour of the gutter guard. And guess where you will go? Answer: Into the gutter most of you go along with the rain water and if there were enough of you from a real close big tree, there is no chance that the gutter will stay flow free but instead clog. If you ask the engineer, the Niagara type of gutter guard works fine if your tree is at least a hundred feet or so from the gutter and the prevailing winds are away from the house.
Instead of one long fin as the Niagara gutter protector if you Google "Care Free vinyl gutter covers" you'll see a row of louvers. Suddenly the chances of a blossom getting to the ground is much easier. Only a few of you will get washed into the gutter than with the Niagara kind of leaf guard.
Yet if you ask the engineer for the best gutter cover, I'll tell you it's a gutter cover with not one but two rows of louvers. Yes, Mr, or Mrs Blossom, can you imagine two rows of louvers instead of one or none? Go ahead and Google "double row louvered gutter guard" and you'll find a bunch of articles written by me --wow I write a lot. To save you time reading them, Google "Waterloov Gutter Guard" or "The Number One Gutter Protector" and voila, you'll see two examples of double row louvered systems.
Now Mr. or Mrs. Blossom, what are your chances of getting into that gutter and causing mayhem?If you ask the engineer, the answer is zero. In the worst case scenario if you are wet you will wash onto the front louvers and cover several of them, but guess what?
The owner of your tree—Mr Homeowner, can easily see you there and save you from an eternal life of being stuck on a gutter guard by using his telescopic pole and brush to dislodge you and speed you on toward the ground along with your friends.
So ask the engineer which is the best gutter guard or the best gutter cover to allow leaves and of course blossoms find their way to the ground I'll tell you it's the two row louvered leaf guard--nothing else. And would you believe that within a couple dollars per foot, most gutter covers (including the foam inserts) all sell for around the same dollars per foot? So, why put a cushion in your gutter?