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Replacing Lintels when renewing double glazing

hifinutt

hifinutt
Can i pick your brains , just trying to buy this house which was turned down by some first time buyers as too much work . Now i do`t mind getting electrics done and boiler renewed and a few other things because they are fairly easy to cost . Had the structural survey done last week and apparently these houses were built without lintels it seems and some evidence of brick drop to some windows . seems crazy to me to build with no lintel.

Anyway to renew the DG would need new lintels , anyone any experience to share and perhaps costs . I have asked a DG company , i dont want to pull out and lose a shedload of money but wondering if i have bitten off more than i can chew

image-0-1024x1024 by , on Flickr


rear view

IMG_0671 by https://www.flickr.com/photos/158267783@N02/, on Flickr
 
Is it a cavity wall i.e. brick block construction or some form of timber frame? Its not alas too uncommon to find dwellings without lintels in some instances the windows were used to support the structure above but as they get replaced this is often overlooked.
If its a cavity wall of 50mm thickness its not too disastrous to put in a lintel when replacing a window though obviously more cost is involved with temporary support and making good especially where end bearings are formed ( min 150mm either side )
I cant tell from this pic but the first floor may be ok if its taking roof load only there are possible work arounds but again at cost.
You could also look into getting a window with a structural frame that may suffice.
 
thanks david , its cavity brickwork and blockwork construction. there is only 2 bricks high on top windows so seems a bit OTT when its been up since the 70`s
 
2 bricks and a roof, you mean. It's ok, as the walls are sound you can slot a lintel in there while the window is out.

As David says some window frames were/are structural. Easy fixed, with another structural frame or a lintel.
 
The house looks 'too old' to have come with patio doors so perhaps they have been replaced once already - the entrance door at the front certainly seems to be different to the windows in that elevation.

Even if load bearing replacements aren't prohibitively expensive, some temporary support will surely be required during the works which will generate a degree of making good. Might as well put lintels in (IMHO of course).

CDphobe makes a useful suggestion....

Jim
 
I really can't believe those spans,c 1.8m+ are 'without lintels' of some sort.
Even just the outer leaf is not being supported on 32mm of softwood frame, and a 4mm sheet of window glass in compression as it stands...

More info required.
 
You would have originally had stronger aluminium Crittal windows when built, when these were replaced with newer plastic glazing (which isn’t structurally bearing) the course of bricks above sags.

All you need do, is remove the effected course of bricks, put in a steel section (in an L shape) 150mm beyond each end of the windows to form the new lintel and then replace the brickwork above.

Do not worry about the house collapsing... you have a cavity wall and the roof is always supported on the inner course... if you go inside and look above the windows, is there sagging? No. That’s because there will be a concrete internal lintel.

It’s just when some houses were built the windows were load bearing, so you didn’t need a lintel on the outer course... when the glazing was changed, the bricks sag on the less strong window frame.


Edit - looking at your first pic you can see that the neighbour to your right has had a third set of windows fitted and they removed two courses and put in a concrete lintel which they painted brown. You can do this, but using a steel ‘L’ section enables you to put bricks back and make it look far nicer.
 
They look like they were built with Catnic lintels, the ones with a slope that forms a DPC above the window. The reason that they are sagging (if they are Catnics), is that the bricks are built on a stretcher bond (above the windows). They should ideally have built the brickwork on a soldier (upright) course above the windows onto the plate of the lintel. This would add strength to the lintel. You can easily check if these lintels were used by looking directly above the windows, under the brickwork, you should see a metal sheet supporting them. The only real way to fix this is to re-bed the bricks on edge above the widows. Hope this helps..
 
The reason that they are sagging ... is that the bricks are built on a stretcher bond (above the windows). They should ideally have built the brickwork on a soldier (upright) course above the windows onto the plate of the lintel. This would add strength to the lintel.
Not true; the lintel carries the lot, and in fact, soldier courses make things a hair worse in theory by having three courses slip planes i.e three courses less 'corbel' action. *

But the brickwork bond doesn't actually matter - the lintel is always factored to carry the imposed loads (masonry leaves, plus contribution of floor span (or roof) in entirety.


*soldier courses for such things go back to aping expectation for a rubbed-brick arch as would have been used before commercial use of lintels for speed - it's a purely aesthetic choice, no use structurally.
 
Not true; the lintel carries the lot, and in fact, soldier courses make things a hair worse in theory by having three courses slip planes i.e three courses less 'corbel' action. *

But the brickwork bond doesn't actually matter - the lintel is always factored to carry the imposed loads (masonry leaves, plus contribution of floor span (or roof) in entirety.


*soldier courses for such things go back to aping expectation for a rubbed-brick arch as would have been used before commercial use of lintels for speed - it's a purely aesthetic choice, no use structurally.
Hmm, yes the lintel will bear the the weight. Those Catnics do have a certain amount of flex in them on the front shelf though, especially on a long stretch, and can sag a little over time. Each to their own, but personally, I would not lay bricks on a stretcher bond in that scenario, if I could help it. The bond actually does matter, there are 'flat' arches in brickwork (which should have a slight lift towards the centre), but they really should not be used over a long stretch.
To lay bricks, as in the above photo without a lintel, is pretty much asking for trouble.
 
My 1956 built house was built had wooden windows and no outer lintels, the inner lintels were concrete.
To replace the inner and outer lintels with one steel lintel like a modern house is a massive job because the inner lintel supports the bedroom floor. Unless there is cracking on the inner lintel plasterwork it is not necessary to replace it.
The solution is to fit an L shaped lintel. Some bodgers fit a small angle iron lintel because they are easy to fit and cheap, this is not a good idea because the front of the brick is not supported and can move. I used Birtley galvanised lintels they are not too expensive, give them a ring, giving sizes and they will spec it for you. To fit you need to to loan 2 props and 2 strong boys .
https://www.google.com/search?q=str...e..69i57j0l5.6873j0j8&sourceid=chrome&ie=UTF-
Scaffolding is required to get the height and i would do the upstairs while you have the scaffolding or you will find your upstairs windows will not open or windows crack or become steamed up with breakdown of the units. The lintel and lower brickwork needs to set before you remove the strong boys and fit the last couple of bricks. Have a couple of supports fitted when you fit the lintel because it can move with the weight if the bricks.
 


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