Safe to screw into vinyl door/window frame?
Trevor_Lambert
| Posted in General Questions on
I want to put some screws into the center vertical frame of a fully glazed door and sidelight assembly.* I’m assuming there’s aluminum under the vinyl at some depth, and that while screwing into probably isn’t ideal, it won’t be a catastrophe. The spot I’m looking at is 2.25″ horizontally from the glazing. Does this seem reasonable? I’ll try to post a picture shortly to clarify what I’m talking about.
*I could go into why, but that’s a whole other story.
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The area I'm looking at is just to the left of the raised strip in the closeup picture.
Often vinyl windows and doors are just that vinyl and glass zero percent aluminum. The will have internal vinyl structures for rigidly Joint are made by melting both parts and fusing them together zero fasteners in the frame except for the latch hardware.
Most places that sell windows will have a cut away model of their window you can inspect.
I would be very reluctant to drill a hole in one of my vinyl windows are you sure that is your only option? I would not expect the vinyl to support much weight.
Walta
I suspect you're right. There's some aluminum inside that's visible if you remove the door latching hardware, but that's probably there specifically for that purpose, and there's no reason for there to be any aluminum elsewhere.
Is the unit under warranty and will drilling a hole void it? Do you care about the warranty? Many warranties are practically useless.
The warranty isn't worth the paper it's printed on. I had numerous problems with doors and operable windows shortly after finishing the house. It took two years of pleading before they finally sent someone out, who only spent an hour trying to fix the many issues. He didn't end up solving anything, and since then I couldn't even get them to return a phone call or e-mail. It's moot anyway, because of what Walta pointed out.
The problem I'm trying to solve is that the center piece bows inward about 1/4". This makes the door difficult to fully close (multi point latch). I have a reinforced wooden frame on the exterior that I installed to hold a roll up screen, and I found I could straighten up the center piece by clamping it to the wooden frame.
So if I can't screw the center piece to the wooden frame, my next idea is to install a piece of aluminum rectangular tube on the inside, secured at the floor and the top of the rough opening. Trying to figure out how big it would need to be in order to be rigid enough to do the job. Does 1x2x0.125 seem like enough? Anyone have any better ideas?
Typically the glass is recessed about 3/4" to 1" into the frame. You can normally see how far exactly it is as there will be snap in retainers on the inside at that depth. You can screw into the vinyl but it doesn't have too much holding power, so it has to be done with some care. Many screws and predrill the wood.
As for reinforcement, you want something stiff. For readily available material, that means steel, much stiffer than AL (about 3x) of similar size. For a 7' tall door, a 1"x2" aluminum section will be pretty bendy, same size steel tube would be much more solid. If you want high tech and small, can't beat a length of carbon fiber tube.
So the 1x2 aluminum tube should be more rigid than a 1" angle iron? Intuitively it feels like 1” angle iron would be enough. Angle iron is going to look a little too industrial, while carbon fiber looks to be too expensive, if I could even get the right size. The longest pieces I could find were 78".
The other way around. A 1x2 steel tube is about 3x stiffer than a 1x2 aluminum tube.
L angle is a very bad shape for bending stiffness. It tends to twist instead of bending, not a good shape for what you are trying to do.
A T or C channel would work and can be easily clad in wood.
I would not try to sandwich the door from the inside and outside as there are big temperature changes and the two materials will expand different amounts causing it to bow. Inside would be better as the temperature is more stable there.
You can try attaching it with screws first. If that is not beefy enough you can look at rivnuts (there are specific ones for plastic) in the vinyl or Snaptoggle bolts. Finding a cross section of the extrusion used will help in figuring out where there is extra meat.
I was comparing 1x2 aluminum to 1" angle iron, so 2 parallel 2" sections of aluminum against the axis of bending versus a single 1" section. That's how I figured the 1x2 would be more rigid; 1/3 the material rigidity but 4x the cross sectional area.
What if I drilled a 1/4" hole all the way through and sucked the two pieces together with a really long bolt?
1x2 x 1/8" wall alum is pretty stiff, depending on the alloy. Very easy to work with as well. The stiffness depends on which way the rectangle section is rotated obviously, because bending stiffness is not symmetrical for a rectangle section. Might not be as stiff as you need if the 2inch side is flat against the door frame, such that the 1inch side is resisting the bending force.
But why not use a length of steel tube instead of aluminum? It should be cheaper and stiffer for a given section profile, and if there is no need for light weight because it will be a stationary piece. Steel is great for stuff like this, and there is likely a steel supplier in your area that can help you out, or a local fabricator that can sell you the odd stick of whatever you need. A piece of white painted steel won't really look any different than the self-color vinyl extrusion that the door is made from. Or cover it with PVC trim board.
To be honest, you don't really know how much force you need to apply in bending, so the answer to the "is it stiff enough" question is either to do some testing and some math, or just to make it far bigger than needed (and then figure out make it aesthetically pleasing).
Angle steel is cheap and readily available, but angle is very poor in bending unless you can constrain it very well against torsion, etc. If you put much load on it, it twists and deflects. That's one of the reasons it's usually so thick. Any type of tube section is size-for-size generally far superior in unsupported bending, especially with anything close to the same section thickness as angle iron. (Edit: Malcolm posted the same thing above, while I was replying).
Whatever your solution, you could add shims or some sort of screw-adjusted preload mechanism to change the amount of load applied by the reinforcing beam to the door frame (shims are likely much easier). That way it's not critical for the reinforcing beam to directly touch the door frame, and it also allows for gap compensation if the reinforcing beam deflects under applied load. Or you can camber the reinforcing beam and load it against the vertical center of the door frame, etc., if you have the tools and ability (again, shims are likely much easier).
If the deflection is to the interior of the building, there's no real reason to attach the reinforcing beam to the door center frame, you just need to push against it in the reactive direction. I don't imagine there should be a reason to drill any holes in the vinyl frame.
Unless the loads from the door frame are very low, it's not realistic to expect that the reinforcing beam is not going to deflect, unless the beam section is pretty stout. As long as you plan for that from the beginning, everything will work out well.
I've priced both out, and surprisingly the aluminum and steel are very similar prices. I can't find any painted steel tubing, just mild steel, presumably already rusting. Given how much easier aluminum is to work with and the work I'd have to do on the steel to make it look presentable, I think aluminum is the right choice. As you say, it doesn't have to have zero deflection. Basically it just needs to be more rigid than the vinyl frame, so that if I shim it, more bending happens in the vinyl than the aluminum.
Over the years I did work for a nearby resort, I ended up taking out almost all the sliding glass and french doors and replacing them with a single man-door and window.
On my own house I have two wood french doors we never open both sides on, that seal very poorly. I'm beginning to think they are another of those things designers like me think are a good idea, which really aren't.
I have regretted these doors for a long time now. I wish I'd just used a single, wide door. A 40" door would have provided almost the same glazing, looked better, functioned better as a door, and been more energy efficient. Installing the roll-out screen was exponentially more work with these doors than the standard doors we have.
Trevor,
It's my sincere belief that when we finally design and build a house where we get everything right, we achieve enlightenment and no longer suffer the curse of constant reincarnation. A sort of architectural Buddhism. I'm still waiting.
Just to close the loop on this topic, I decided to try just screwing into the vinyl. Removing the steel catch and looking at the cross section of the vinyl frame, it appeared there are three layers of vinyl I could penetrate with a 3/4" screw. I used an aluminum "strap" that I made out of a sheet scrap about 1mm thick. For one door, I used a total of 6 screws. For the other door, which requires about double the correction, I used a bigger strap and 14 screws. So far they are holding up well. The first door has been restored to essentially optimal function, while the second one is vastly improved, but could still be better. I might add the 1x2 aluminum tube on the interior side of that door at some point.