Vinyl cannot "rust", physically impossible. But I would say you have water leaking from somewhere above and possibly nails, joist hangers, steel lintel or something in the wall cavity somewhere is rusting and the resulting water is staining your vinyl. You may have serious issues and it may be a simple fix but you need to get it addressed before you do the final walk through.

Yeah sorry I know it's not the vinyl itself that is rusting but I wasn't sure if they were vinyl clad if perhaps there is some metal that would fasten the vinyl to the wood? It really doesn't seem good that I can see rust in the seams if they were tight and sealed too! Unfortunately, all the reviews I've read on the brand are horrible. To me I'm wondering if the windows and installation are both defective?

The " vinyl hinge" on the exterior part of the sill is a horrible design. This means its not a true welded sloped sill. Rather than water ONLY drain from the sill, a window with " vinyl hinge" ober weep holes mean water also drains through the frame. This is a very bad design..why ??? If you ever noticed debris on your sill, water carries that debris in tne frame and ultimately clogg those weep holes. Once clogged, it is very hard to unclog which mean mold developes. Also, i have seen trapped water freeze and actually crack the frame and cause water to run inside the walls.

From my seat it is impossible to tell. You probably will need the builder to pull the window and find out what the hell is leaking.

+1

The vinyl cannot rust but perhaps a fastener or hardware piece inside the window is rusting.

That sill should not be holding that kind of water for that much time anyway so as to allow for continued and significant oxidation like that.

What is going on with that brick work too? That soldier course looks super odd to me.

Was that opening original or added as a modification?

I think the brick is a bit unlevel or wavy. It's a new construction so the window is original. Sad what quality new builds are in my area!

We are asking the builder to fix/replace the 5 windows with rust, but even then I think we will need to replace the sliders with a better brand in a couple years after reading all the poor reviews.

It's interesting that the problem is limited to sliders. What brand are the windows? Do the casements also have the hinged style weep holes? Some vinyl manufacturers use steel corner keys to make their sashes or frames more rigid, I suppose if water was backed up or was coming in from above it could create a problem like this. Are there any signs of rust or water on the interior, specifically the track area?

My other thought was to take a look at the spacer bar between the glass. Look at it for signs of corrosion. It would take a lot of moisture to create a problem this bad. I have seen a Milgard window with about 6" of water in between the glass. But again unlikely for 5 windows.

They are MLC windows. A lot of reviews have interior water damage after 5 years from their sliders! From looking at their website it appears the president has the same last name as one of the big builders in my area.

The casements don't have the same style weep holes. I need to look again this weekend, but they have some sort of plug in them (I'll get a photo). I want to get a closer photo of the rust too.

We are trying to get into the house again this weekend to take a better look at the inside of them. I know there wasn't signs of rust inside but not sure about any traces of water in the track.

Sorry extra post

This post was edited by Lifesaver24 on Sat, Jul 20, 13 at 11:30

+1

I would ask the maker of the window for the design drawings and manufacturing specifications.

If there is metal in that corner key or anywhere inside the weeping pathway, that is going to be problematic.

Normally, the window would drain and there would not be pooling water that would foster the oxidation. If the window was installed a bit out of level and it is pitched towards the home and therefore holding water, that is going to create a pool for the rust to feed on.

Lifesaver24, how did you resolve the window issue? My new home in MI is about 45 days from completion and one of the MLC windows have started to rust.

Would love to hear an update from those that had this issue on their new build houses. We are about to move into one in michigan as well. Our neighbor is having the same