Hello all,

I have a "semi-detached" garage that is attached to the residence if
that makes sense.

Its of typical 2.5m by 5.0m long dimensions.

It has 5 Fink trusses on it with a stonewold tiled roof.

I have been given a load of flooring joists that are 3m long and would
like to turn the garage loft into a usable storage space to be
accessible by a loft ladder.

Now, As you open the up and over garage door, to your right there is a
double skin wall between the garage and the main house which is of
clinker block construction (both skins)

On the left hand side there is a single skin brick wall that has two
brick pillars about 2m in and 3m in. There used to be a window between
these two brick pillars. This window has beeen removed and bricked up.
The original steel lintel has been left in place and is supported by the
two brick pillars.

My proposed plan is to cut a rectangular hole 2.5m of the way into one
of the skins of the double skin wall.

I would then put a pair of sistered flooring joists into this hole and
the other end to sit on top of the original window steel lintel. (this
lintel looks like it was originally meant for a double skin wall so it
has a ledge on the inside between the two brick pillars. The top edges
of this sistered joist would come up to the bottom edges of the fink
trusses.

I then plan to fit two sets of flooring joists, one set from the steel
lintel that is above the garage door to the sistered joist pair. The 2nd
set would run from the back wall which is a double skin wall to the
sistered joist pair. The span from the middle to either front or bac of
garage will be less than 3m.

Now does this sound structurally sound so far? The query I hhave is that
the sistered joist will effectively sit on 4 inches of support as
opposed to the recommended 6 inches, which is why i think sistering the
joist could be helpful as that doubles the support contact area.

Now I was wondering what to do about the Fink trusses? There are 5 of
these.

Access to these trusses is easy from the inside as there is no ceiling
in the garage.

The outer two fink trusses I am not bothered about as they are up
against the gable walls at both ends. So that leaves 3 trusses. Can I
convert these into Attic trusses with some suitable carpentry to make
better use of the space?

I then plan to put a chipboard caber floor in this loft space and fit
some lighting.

Any comments?

S.