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    Hello, newbie here, though I've been lurking for a little while. :)

    Apologies if this is too dumb a question or if this has been asked before (I did a search but could not find anything; and google search returned little of value). I've had replacement double glazed timber sash windows fitted in my Victorian house. The installer used plastic wedges/shims, driven from the inside, to get the windows to sit plumb, and then filled all the remaining gaps with expanding foam (Soudafoam gun). So far, so good.

    I've asked the internal refurb builder I normally use to make good the windows internally (plaster the damaged walls and fit architraves). He has swiftly pulled the plastic shims out and is saying that the foam should now hold the windows in place and the shims are not needed. He's added that the shims are also a cold bridge, and may cause condensation if left in - on that he is right, of course.

    Is pulling out the shims after the foam has set a standard practice? Is the foam really enough to hold the windows plumb and in place?

    Many thanks in advance for your help.
    • CommentAuthortony
    • CommentTimeMay 24th 2016
    The shims are not a cold bridge, the foam will hold the window in place. I would not have pulled the shims out as doing this could leave air leakage paths.
    Thank you!

    The refurb builder is proposing to fill the gaps left by the shims with more expanding foam to prevent air leakage.
    It sounds from your reply that as long as this is done, the foam should hold the windows just fine?
    • CommentAuthortony
    • CommentTimeMay 24th 2016
    Yes, good practice would be to add some mechanical fixings carefully too though the foam and silicone will in practice hold tem in place on their own til something goes wrong.
    • CommentAuthorgyrogear
    • CommentTimeMay 24th 2016 edited
    Posted By: girdersofbabelThe refurb builder is proposing to fill the gaps left by the shims with more expanding foam to prevent air leakage.

    good practice (and rare in my (admittedly limited) experience)

    • CommentAuthortony
    • CommentTimeMay 24th 2016
    Generally windows are fitted using mechanical fixings.

    I am now having visions of a big person climbing out of a window and finishing up on the floor all tangled up in a broken window.
    Thank you for your comments, both! I've also spoken to the window company who say that removing the shims is not a problem.

    Generally where we have straight brick reveals, the window installers have actually bolted through the frames to mechanically fix into the brick. Where the brick reveals are rebated (older Victorian construction) they haven't been able to do that, so these are currently just wedged in, with foam infill. At least with these latter windows, the good news is that someone from outside can't just pop the window out, it can only be done from the inside, and the window can also only fall inwards too! :/ Maybe leave the shims in for these ones, then?
    • CommentAuthortony
    • CommentTimeMay 24th 2016
    It should be possible to drill diagonally through the frame and into the outside skin of the window reveal.

    I would do this, we used to get sliding sash windows out with almost no damage by simply pulling hard inwards, sometimes after easing the few tiny nails going into the wood head lintel, often this came out too!
    • CommentAuthorDarylP
    • CommentTimeMay 24th 2016
    I haven't screwed in window frames to the reveals for years now. (low)-ex foam does the trick. Never had one blow in, or out. Even in windy N. Wales..... :cool:
    Yep, any modern window fitter will shim and foam fit. Some don't bother with screws, but I always prefer a couple for a little extra security. When I've fitted myself, I've always removed the shims once the foam has cured and filled in this void with more foam - why waste the shims?!
    • CommentAuthorgyrogear
    • CommentTimeApr 22nd 2017 edited
    Posted By: tonyIt should be possible to drill diagonally through the frame and into the outside skin of the window reveal.

    Just resurrecting this, for a different reason...

    I would like to feed a plastic (MLC) or copper pipe through my frame (jamb), for some solar thermal. Outside diameter would be 23 or 22 mm - I think I have 40 mm to play with on the frame. I would "try" and scrounge as much as possible out of the wall (block and cement render), to save the aluminium regardless.

    Does this proposal raise anybody's eyebrows ?

    • CommentAuthorEd Davies
    • CommentTimeApr 22nd 2017
    Sorry, no idea about the window aspects but stainless pipe would be a lot less heat conductive than copper.

    Copper 401 W/(m·K)
    Stainless: 16 W/(m·K)

    • CommentTimeApr 22nd 2017
    If you can go through the wall instead of the frame, why not do that?
    • CommentAuthorgyrogear
    • CommentTimeApr 23rd 2017 edited
    Posted By: djhIf you can go through the wall instead of the frame, why not do that?

    Thanks for that, gents !

    I am in a reveal situation - the jamb is jacked against the wall face, and (presumably) foamed in, then covered on either side (EXT and INT) with a cover strip.

    So the "easiest" solution (depending on feasibility) would be to go through the frame, period.
    It is a patio door, 2.4 meters wide, and still under waranty for another 12 yrs...
    My suggestion would no doubt invalidate the warranty...

    I could try and "avoid" the frame completely, by digging out the wall surface to several centimeters, then "tunneling past" the jamb, without touching it at all, but it sounds like a bit of a civil engineering job to me...

    I suppose I could ask the original installer to come out and do it for me, if he agrees.
    Alternatively, I have another bloke coming to do me a garage door in a few weeks, maybe get *HIM* to do the operation as a back-pocket job...

    The tube in question comes into the reveal, off my facade. So it does not really need to be going through the wall at all...

    Posted By: Ed Daviesstainless pipe would be a lot less heat conductive than copper.

    Yes, thanks for that Ed, agreed. The rest of the collector is in copper, so I wanted to avoid a change of metal, I could just about manage a soldered union, or a transition to PEX, but SS sounds a bit complicated...

    I could put up with a few lost watts ! However, a lost window would set me back a bit in "more ways than one "...

    Will try to attach a poor-man's sketch...


    It is funny how this happens, but discussing it with yourselves, it is obvious that I need to remove the two cover strips and get eye-to-eye with the jamb and see how it is set up - in a miracle situation, there might be enough space between the frame and the wall to take the pipe as-is, by just cutting through whatever insulation or sealing is in there... PMF (pigs might fly...).

    so thanks for all the help !:smile:
    • CommentAuthorcjard
    • CommentTimeMay 4th 2017
    I'd still nip down to the hire shop and get an SDS drill and massive drill bit and go through the wall (if I didn't already have an SDS drill and massive bit, or course)

    +1 for getting your back door tradesman to bash your hole for you.


    I'll get my coat
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