enlarging a window

[seneca]

I have an old wooden frame window that needs replacing and I want a UPVC one in it's place. However, I've been pondering that since it is a tiny square window, it might be worth getting the window hole widened for a larger rectangular shaped window. So, how big and difficult a job is it to extend a windows width. That is to say enlargening it horizontally, not vertically. I want to know how much work is involved and what it entails. Also a rough figure on how much it should cost. (so I know if a quote is reasonable and the correct amount of work is undertaken.)

any advice would be appreciated

 

[Scrit]

Most windows have a lintel in the masonry above them (to support the wall above the opening). If you widen the opening you will in all probability need to chop out the existing lintel and replace it with a longer one. I'd consult a builder if I were you.

Scrit

 

[noseall]

if you are increasing the window's width to more than 1800mm then you may need to get calculations for the lintel steel.
as scrit said. making an opening wider is tough, unless you're lucky and have a large lintel bearing at present.
100-150mm is the accepted minimum for lintel bearings.

 

[salem2000]

You will also need to advise your local Building Control Officer.

 

[seneca]

The window measures 53cm across and is 63cm high. It's just a tiny window in the box room, but it's a bit dark in there and there is a nice view. How can I tell how long the lintel is and where it starts and ends. I know that the wall is 2 brick thick with no cavity.

 

[noseall]

if the wall is solid 9 inch brickwork, and the original window wooden, then the chances are there is no external leaf lintel.
there will probably be only an internal masonry lintel.
this will most likely be a cast-in-situ concrete lintel.

if this is the case then a professional may be needed to carry out the work.

if you hack the plaster off internally, from above the window, it will expose the lintel. it will probably have 4 to 6 inches of bearing and be 2 courses or 6 inches thick.

 

[seneca]

forgot to mention the window faces the back garden and is an upstairs window. In fact the roof beams come out from under the roof and are just above the top of the window. I imagine there will only be a few bricks worth of space until the roof was put on. Does doubling the width require planning permission? It is a 30's detached house and the neighbour has a wider window. I'd ask him about it, but he's never around.

 

[noseall]

i doubt planning permission will be needed but building regs is likely.
a catnic type lintel that deals with 225mm brickwork will be ok for a window opening less than 1800mm wide.