Sealing large gap around replacement vinyl windows

Discussion in 'Remodel Forum & Blog' started by Mikey, Oct 26, 2006.

  1. Mikey

    Mikey Aspiring Old Fart, EE, computer & networking geek

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    2,726
    Location:
    Central Florida
    I'm replacing the old aluminum single-glazed windows with vinyl low-E triple-glazed, hurricane-proof, high-test windows. Because of the way the original windows fit, the generic replacements end up with a 1/2" to 3/4" gap around all sides at the outside edge. It's a brick house. I'm wondering what to use to fill up the gap that will seal to both the brick and the vinyl and look good. Ideally, it would look like the mortar in the surrounding brickwork, so I'm thinking of using mortar or a modified grout or something similar. Not sure it wouldn't slump out of the vertical gaps, though. Suggestions welcome.
  2. Verdeboy

    Verdeboy In the Trades

    Messages:
    2,051
    There is a caulk that is made specifically to look and feel like mortar. It's called "Mor-Flexx". On the tube it says, "Looks like mortar - Stretches like rubber. It has a sandy texture to it and it's gray. It can be painted if another color is desired.
  3. Mikey

    Mikey Aspiring Old Fart, EE, computer & networking geek

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    2,726
    Location:
    Central Florida
    I'll see if the local Ace Hardware has some on the way home. At $7+/cartridge it's pretty pricey, but if it works it sounds like it's just what I want; thanks for the tip.
  4. Cass

    Cass Plumber

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    5,980
    Location:
    Ohio
    When you go to look a the caulk check and see what size gap it will fill. Then check and see if you can caulk over the caulk.
  5. Verdeboy

    Verdeboy In the Trades

    Messages:
    2,051
    If the gap is as deep as it is wide, I'd stuff some foam backer rod in there first, then use the Mor-flexx over that.
  6. Verdeboy

    Verdeboy In the Trades

    Messages:
    2,051
    I bet those windows ain't cheap neither.:eek:
  7. Mikey

    Mikey Aspiring Old Fart, EE, computer & networking geek

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    2,726
    Location:
    Central Florida
    You got that right. The top-o'-the-line laminated, hurricane-proof, Argon-filled, low-E (or maybe high-E, I forget), triple-pane, 200-proof, low-fat windows are $586 apiece :eek: (anything up to 52" wide). Fortunately, lots of my windows are 52", so I'm getting my money's worth. Bathroom, unfortunately, is 27" :( .

    Turns out Ace doesn't stock Mor-flexx, so I'm still looking for a source for just a tube or 2 to try. Lowe's never heard of it. Got some backer rod today, but largest size is 5/8" -- really could use a lot bigger in some cases, but I'll make do. Using some polyurethane foam to fill the bulk of the gap, and act as a structural sealant to firm up the window installation - it's held in with Tapcons, but it's a little shaky until the foam sets up, then it's rock-solid.

    Another option I'm looking at is a product from Custom, called ProLite (http://www.custombuildingproducts.com/ProductCatalog/SettingMaterialsDIY/ArchitecturallyEngineeredMortars/prolite.aspx?user=diy&lang=en) which is a lightweight, non-slumping mortar, but I doubt it will work in the big volumes I'm concerned with, since it's intended more for tilesetting than gapfilling. I've e-mailed them to see if they've got other suggestions.
  8. Mikey

    Mikey Aspiring Old Fart, EE, computer & networking geek

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    2,726
    Location:
    Central Florida
    Custom said they've got nothing that will work. I then went to the Mor-flexx Website, and found they have a great deal - 4 tubes for $24, shipping included - for a trial. Can't beat it! I guess it'll be a week or so before I get it, but I'll let you know how it works.
  9. Verdeboy

    Verdeboy In the Trades

    Messages:
    2,051
    The other caulk I use all the time around large gaps in windows is called "Big Stretch." It's actually a lot easier to work with than the Mor-Flexx and is 1/2 the price. It doesn't have the sandy texture of the Mor-Flexx, but it may stick better to the vinyl substrate. The Mor-Flexx is made to repair cracks in mortar, so it should stick real well to the mortar substrate, but I'm not sure how it will adhere to the vinyl.

    I get the Big stretch at my local "Do it Center" hardware chain and the Mor-Flexx from "Foxworth - Galbraith".
  10. Cass

    Cass Plumber

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    5,980
    Location:
    Ohio
    Just remembered I used something called Building Caulk, it is a commercial product not sold to the general public. A friend of mine works for the company and it is used on sky scrapers where thay can't afford to be replacing caulk. Has a 100 year life or something like that. I will contact him and see what I can find out about getting some. Do you have any idea how much you need and what color?
    Last edited: Oct 28, 2006
  11. Mikey

    Mikey Aspiring Old Fart, EE, computer & networking geek

    Messages:
    2,726
    Location:
    Central Florida
    Thanks, Cass -- 100 years would be good enough for me. It calculates to about 165 linear feet of gap. On the two windows installed so far, the gaps range from 1/2" to 3/4", and are about 1 1/4" deep, but I'm going to fill some of the depth with foam or backer rod. All in all, a very liberal estimate would be .85 cu ft of caulk, allowing for some waste. Best color would be either grey (to match the brick mortar) or very dark brownish red (to match the brick).
  12. Verdeboy

    Verdeboy In the Trades

    Messages:
    2,051
    The main consideration is that the caulk be flexible. Once a caulk gets brittle, it cracks and leaks. According to the "Big Stretch" tube, it spans gaps up to 2inches, and you will "never have to replace your caulking again".

    Never is even more than 100 years, though I don't know how they can prove it.:cool:
  13. Mikey

    Mikey Aspiring Old Fart, EE, computer & networking geek

    Messages:
    2,726
    Location:
    Central Florida
    I called Sashco and a very nice lady assured me that Mor-flexx would adhere to the vinyl just great. Probably they use fundamentally the same chemistry for all their products. I'll give the sample kit a try and let everyone know what happens.

    Also, I just went outside and measured all the window openings. There's a fair amount of variation, but the average gap will still be in the 1/2" range.

    Found out the "pro" installers are getting $55/window to do the installs. First crew of 4 took all day to not-quite install the first window. 2nd crew of 2 took all day to almost-completely install the first one and the 2nd one. All that's remaining on them is the finish caulk, and now that we know where the rocks are I think we could knock out 2 per day, but so far no other crew wants to take the job.
  14. Alex Caulk

    Go to lowes and buy a tube or two of ALEX caluk by Dap.....

    I got it spread all over the outside of my house in teh CEAR color,,

    sealing up old cedar sideing that had some large gaps in it.....


    it comes in various colors and works pretty well for a good tight seal

    and has a 35 year warranty.... it only costs about 2.35 per tube

    and goes on like a dream.......

    take a tub efor a test run or just use it for filler and top it off
    with the expensive stuff.
  15. Verdeboy

    Verdeboy In the Trades

    Messages:
    2,051
    Who could blame them. The first crew made 1.75/hr. The second crew made 3.50/hr. Reminds me of when I worked as the maint. manager at a very laid back massage school in northern California. I picked up a used window to give our shop some much needed light. It took a crew of 6 about a week to install the thing. It was very large and weighed a ton--and it nearly wiped out my whole crew. They were making 300.00/month, so the wages were similar. We had nice perks, though, like a 70/30 ratio of females to males and all the free massages you wanted. ;)
  16. Mikey

    Mikey Aspiring Old Fart, EE, computer & networking geek

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    2,726
    Location:
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    And you LEFT that job?
  17. Verdeboy

    Verdeboy In the Trades

    Messages:
    2,051
    Even that Garden of Eden had its down side. The owners wanted everything done professionally, but we had too many slackers on the crew. We couldn't pick and choose our workers because of that $300.00/month thing. So, there was too much stress on the managers like myself. Plus, it was a vegetarian/vegan place and I've got to get some animal protein in me once in a while.
  18. galacon

    galacon Master Electrician & Engineer

    Messages:
    11
    Location:
    Northern Illinois, USA
    Mikey-

    Too bad we didn't run into each other earlier. As one of my sidelines I am a distributor for a very high quality custom vinyl window manufacturer here in Chicago, and you could have bought your windows custom, sized to the individual openings +/- whatever gap you wanted, delivered to FLA, for less than you paid the big-box. Oh well...

    Anyone else with this prob, let me know and we'll try to hook you up!

    G
  19. Mikey

    Mikey Aspiring Old Fart, EE, computer & networking geek

    Messages:
    2,726
    Location:
    Central Florida
    NOW you tell me. This wasn't a big-box, it was a local company specializing in windows and doors -- Window Depot, if you can believe it. The windows were manufactured by Accu-Weld, which seems like a decent outfit. The windows are listed in the NFRC database. Prices were a little lower than big-box, ranging from $169 to $563 (laminated double-glazed), independent of size.

    The problem is they didn't understand how the windows were going to have to be installed, and consequently didn't measure them properly. In the case of 4 windows, they are at least 5/8" wider than the interior opening. If they cut the drywall on the inside jamb, they might be able to make them fit, but I'm concerned about the final appearance. There's no question in my mind that I could do a better job of installing them, since their installers are paid by the window ($55), so they aren't terribly concerned about doing it right.
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