Replacing wooden lintel over door

[yungbeattie]

advise please

Have a mid 19th century stone house. In the basement I have discovered a old doorway leading to a passage way, below street level, which runs along front of the house. The lintel over the door is wooden and appears damp and rotten at one end. I am happy to seal the doorway up as the passage way comes to a dead end.
Therefore:-

1 Should I go to the bother of replacing the lintel?

2 Can I just brick up the doorway to the lintel even if it is damaged?

3 If I can just brick it up what is the best type of block or brick to use

4 If I can brick it up should I allow for ventilation?

5 Or should I get a builder in

yes just in case you hadn't work it out I'm a novice

Cheers
yungbeattie

 

[adapt]

replace the lental with a concrete one, support each side of the doorway with a some 3" x3" posts. Make sure the new lental is the right size before starting. if you brick it up use enginering B bricks about 30p each from diy shop put a air brick in about 3rd row of bricks.....

 

[Chukka63]

If you replace the lintel id go for a box lintel,lighter than concrete (assuming its a load bearing wall).
If you block it up id use a light weight block as its easier and quicker and easy to remove in the future if anyone wanted to.(dpc required)
Yes id vent the area.