Hi, I live in a semi detached bungallow which had an internal garage, a few years back we had the garage converted into another room as part of the house, the garage door bricked up & a double glazed window installed. To raise up the floor level to suite the exsisting a wooden floor was layed and an air brick put in under the dpc of the new wall.
On the outside of the property we still have the concreate driveway which runs down towards and butts up to the new wall and also there is a single brick dividing wall (appox 3 foot tall) between us & next door which also butts up to the wall.
I have noticed over the past 6 - 8 months that there is a damp patch appeared in the corner of the room where this dividing wall butts up, and has become worse the last couple of months since my son moved in there as his bedroom,and now every time we wolk in there there is a positive smell of damp, we have had to move him out as he has contracted a chest infection.
A few things I have noticed is
1. The double glazed window gets very wet inside and water runs onto the window sill.
2. The roof gutter was leaking directly above this dividing wall and because off all the rain we had was constantly dripping onto the joint of this divider wall & the house, (This has now been repaired).
3. The concreate drive where it butted up to the new wall had a large chunck missing allowing water to run down and under the drive (again this has been filled in).
A couple of suggestions that have been made to me are
1. Becasuse the 3 foot dividing wall buts upp directly to our house wall this could be allowing water to enter the house, someone suggested tacking away the motour from where it butts up & putting in a membrain to stop the water.
2. Even though there is an air brick below the wooden floor, becouse this old garage room is effectively separate the the rest of the house air brick is not working correctly so it was suggested that I put another air brick in above the floor level just underthe window to remove the condesation.
Sorry if I have rabbited on a bit but my question is would doing these two suggestions above cure this problem or would I have to do more, say remove the drive etc,
any suggestion would be most appreciated and thanks for your time.