Small window, Do I need a lintel?

JonathanAl

Hello folks,

IMG_2023-12-16-21-13-12-475.jpg

1940's little cottage. Not 100 % sure of lower wall make up but from eve height on gable to apex is 300mm mass concrete.

I want to put a little window in here but could I get away with no lintel? Nothing resting on gable as far as I can see and no purlins.

I don't have a lot of "meat" at each window corner so getting a lintel in would be even more problematic. Any thoughts? I have choice of 2 windows, pvc one on diagram, other is 64 cm but very strong teak. I have attached a rough diagram.Thanks very much in advance.

Le shovelle

I don't think you've enough weight above the opening to get away without a lintel. A few100mm x 75mm lintels with 150mm catch each side would suffice for anything less than a metre wide.

JonathanAl

thanks Le Shovelle, appreciate the reply. Perhaps there is a thinner lintel I could use which I could slot in.

sydthebeat

The triangle of masonry directly above that window, 590mm wide, to the same angle as the roof, needs to be supported. If it's not then youre purely dependent on the adhesion of the masonry not to fall in.

In an old cottage I wouldn't be taking that risk. 200 years ago they used timber lintels

JonathanAl

thanks Syd. I understand. As I have very little room to work with for lintels, am now thinking some 100mm angle iron slotted in and bedded, one from each side. If I then use the teak window it is extremely strong (100mm double frame thickness)

sydthebeat

Windows are not designed to take any weight at all. Even a small deviation could break the glass.

Can you take out all the masonry right to the ridge?

Then get a proprietary Window made to shape?

Le shovelle

100mm angle would work but make sure you get it galvanised. I think Syd may have the best solution in removing all the masonry above the window.

JonathanAl

thanks Lads, Regarding demolition of the upper gable I am loath to do that, especially in this weather.

I have overcome the lintel issue.

However a greater issue seems to be the risk of the concrete cracking at the corners of the windows as there is not much "meat" there. Also, this gable receive the brunt of the westerly winds which again may prove too much for the thin corners.

Perks

https://www.boards.ie/discussion/comment/121547350#Comment_121547350

What about a lime mortar married with some mesh, something breathable. What's the make up of the wall under the window?