Internal doorframe removal

[Ric199]

Hi all new to this forum and hope someone can help.

I have an old extension (first floor built over garage), to access the first floor extension one bedroom has been divided with stud wall to create an access corridor, the start to the corridor is the original door frame (now without door).

I would like to remove the doorframe which is narrower than the corridor. The door frame is in a load bearing wall but does not appear to be load bearing in its own right, removal of the trim and plaster above the door shows a wooden lintel 4x3".

Can I remove the frame without issue as the existing wooden lintel is bearing the load?

Can I trim the wall 5" on one side to finish the corridor?

What is the maximum span for the wooden lintel (current span is 35" which would be increased to 40" by trimming the wall).

Lastly how much lintel recess should I ensure is in place before / after wall trimming on each side of the opening?

Thanks .....

 

[noseall]

You should have minimum 100mm bearing on the lintel ends.

If you still have this by the time you have done all your knocking about then you should be ok, otherwise replace the lintel with a concrete fella.

 

[noseall]

Can I remove the frame without issue as the existing wooden lintel is bearing the load?

Can I trim the wall 5" on one side to finish the corridor?

What is the maximum span for the wooden lintel (current span is 35" which would be increased to 40" by trimming the wall).

Yes.

Probably.

40" will be ok. are there any unusual loads above the lintel?

 

[Ric199]

I would estimate there are 5 brick courses above the lintel, there does not appear to be any abnormal loads on this area of the wall as the roof purlins are at least 6ft from this area of the supporting wall.

 

[tony1851]

The old rule for 4" wide timber lintels was: "span in feet equals depth in inches"
So for a 3-foot opening, a 4"x3" timber would be fine.

Strictly, a 40" gap would take you over this 'rule of thumb', but if its only a few courses of brick above, you will be OK with that.

Is the timber long enough? As has been pointed out, you need a reasonable bearing each end but, as the load is relatively small, you would be OK with less than the usual 4", but I shouldn't go much less than 3" if possible.