Working with flashing and beading

[ghcoe]

I have been working with flashing and beading for some time now. I realized that it takes a bit of finess to work with. So thought I would start a thread on how I work with it.

I have been mainly using 2x3 and 2x2 flashing that is available at HD and Lowe's. Flashing can be found in the roofing section. The dimensions of the flashing are exact, unlike wood, so a piece of 2x2 flashing is actually 2" by 2". This works great with the 2" foam since you do not have to worry about material thickness differences.

The beading is used with dry wall. There are quite a few different types of beading. There is plastic, metal, paper covered metal, corner, bull nose (rounded), ect. I have found the best selection at HD, but Lowe's carries the one I have been using which is paper covered metal.

Some examples of how I have used the flashing and beading.

 

[ghcoe]

A few more applications.

 

[Olddog1-TNT]

ghcoe, I can't see but a few mechanical fasteners and they seem to be at joints. Is the beading attached with adhesive and if so what type?

 

[atahoekid]

As logical an application as that is, I can't believe that I never thought about it as I built the Road Foamie. It would have certainly made certain parts of the build easier.... I'll store this in the back of my skull somewhere for use the next time!!!!

 

[pchast]

I think flashing used on my door edges may have
improved gasketing on my unit...

 

[atahoekid]

You're probably right. One of the things that I think helps create a good seal is a defect free surface. The flashing certainly provides that...

 

[ghcoe]

ghcoe, I can't see but a few mechanical fasteners and they seem to be at joints. Is the beading attached with adhesive and if so what type?

I am using mostly using Great Stuff for flashing attachment. Seems to hold quite well unless you forget to clean off the flashing with alcohol first. I try to handle the flashing with gloves on once cleaned off to keep from reapplying more oils.

For the beading I have been using Gripper, although that may change.

I am using pop rivets at key locations.

 

[ghcoe]

So to start measure the length you need. Once the length is measured I use a small square to make my cut line. Then take a straight cut tin snip and make the cuts. Quick and easy.

 

[ghcoe]

Once cut I check to see how the angle of the flashing looks.

Usually the angle is a bit obtuse. This will work fine for inside corners. You want a little bit of presser from the angle to keep the outer edges down along the surface you are applying to.

If you are going around a outside corner you will want to bend the flashing a bit acute so that the same idea applies. A slight spring pressure to keep the edges down along the surface your applying to.

I also try to make the edges as straight as possible. Usually they are straight, but sometimes you will find that they will be bent.

 

[tac422]

This is a GREAT idea !!
I copied this for The Big Pink, but I used the plastic moldings. They worked really well with Gripper.

 

[ghcoe]

I have used both Gripper and Great Stuff to attach the flashing and beading. I have found that I like the Great Stuff better for the flashing. Usually I will spray the Great Stuff onto the flashing and then take a piece of scrap foam and mash it down and spread it to cover the entire side of the flashing being glued down. By spreading the Great Stuff it will cut down on the hydraulic effect of the foam as it cures. It will still foam up, but is much more controllable. When applying make sure that the flashing is seated all the way down to the corner. This is were the slight spring action of the obtuse or acute angle needs to be just right. Pictured below is a piece of flashing with both Gripper and Great Stuff applied.

Clamps are applied. I only need to apply clamps to one side since the spring action of the angle will hold the opposite side down to the surface.

 

[ghcoe]

I am going to walk through a vent reinforcement/hard point installation using flashing.

So I have a cutout in the foam for a roof vent and I have a roof vent. The dilemma? I need hard points to screw the vent to on the roof and inside for the garnish. Also in cutting a hole for the vent it has weakened the roof some in that area.

The cure....... 2"X2" flashing.

First I put on gloves and then wipe down the flashing with alcohol to remove any oily residue that may be present. The gloves protect my hands and keep me from getting more oil on the flashing. This will help with glue and paint bonding later.

 

[ghcoe]

So the vent is made for a 14"X14" hole. I take my measuring tape and measure and make a mark every 14" to make a square.

Then I take a small square and make the cut lines on one side of the angle.

On the last cut I mark a cut line on both sides of the angle.

 

[ghcoe]

Now I take a straight cutting sheet metal cutting shear and make the cuts along the cut lines.

After the cuts I then need to make the bends. I used some scrap 1/4" flooring I had laying around to make a simple sheet metal break. I placed a piece on each side of the angle opposite of the cut and clamped them down. Make sure the ends are even with the opposite cut on both sides of the metal.

Then I place another piece of the 1/4" flooring on the other side of the cut butting it up to the wood I had already clamped down. Now using the flooring as leverage at the bend I bent the metal over.

 

[ghcoe]

So not being a perfect sheet metal break you will not get a nice crisp bend.

But, if you take a flat faced hammer and lightly tap the metal against the wood clamped for the break you can make it crisp. Tap very lightly and evenly so you do not get any hammer marks in the flashing.

You should get something like this.

 

[ghcoe]

So now I have a nice square to fit into the vent hole on the roof. This will hold everything nice and square and give a edge to screw or pop rivet the roof vent to once installed.

One thing that is very important in installing the flashing is that you want to make sure you have no spots in you cutout/surface that is not true. You want the flashing to fit but not be pushed by it's surroundings. If it does not fit relaxed it will buckle or lift due to some stress from a tight spot in the cutout.

Install and check for a nice clean fit.

 

[ghcoe]

If you want a more finished look on the corners you can make a simple cutout to fit nicely under the flashing.

By putting it under the flashing you will make it stronger if you have to screw something into it at that location. If not I suppose you could just make a cutout that just fits in the open space. You could do a radius too.

 

[ghcoe]

So now that I got the top square done it is time to do the inside square. I will be doing the inside square a bit different because I do not have the tools that are exact enough to make a perfect square 1/16" smaller than the top square. If the top or bottom were not perfect in fitment size it would cause the flashing to distort once I attached them together. So to overcome this I will make two angles.

To start I will mark a cut line at 13 7/8" to allow for clearance to fit inside the top square.

Make the bend as before and check for fitment. This one turned out perfect and stays in place without assistance.

Make another angle and fit for size. If any one of the angles is too long to fit you can sand down that side till you have proper clearance. By using two angles you can get the corners to fit right and if your a little short on one side or the other it will still fit nicely. It does not matter if you are a little short ether.

 

[ghcoe]

So I have not done it yet, but the idea is once I am ready to make these squares permanent I will clamp the top to the bottom and pop rivet them together. The angles, once pop riveted together, will create a channel that will give the foam extra support in the cut out area as well as a hard spot for screwing the vent and garnish in place.

 

[ghcoe]

Now onto a simple hard point.

So you have a place that you need a hard point for attaching something in foam. Well you could use wood, or you could use this simple method.

You will need a soldering gun for this procedure. I have a actual gun, but I believe a soldering tool would work if it had a long enough point.

I will be using a scrap piece of foam and flashing for this example.

First make a piece of flashing the size you need it. In this case I used a piece of scrap about 6" long. Now place the flashing where you need it upside down with the angle away from the cutting edge.

Next, take the soldering gun and get the tip hot. Use the flashing as a straight line guide for your soldering gun tip and make a straight slot. Make sure you go down deep enough for the angle to fit.

Now flip the angle over and install into the slot you just made to make sure it fits. Now all you need to do is glue it into place with GG, GS or Gripper. I think I would use GS in the slot and Gripper between the wall and the angle so I would not get any lifting form the GS. This should hold most light items or hinges.