Best fastener for 4x1 wood against coke-breeze wall
 

We have an airing cupboard consisting of CW tank over HW cylinder.

The cupboard is built into the corner formed by a double-brick rear
wall &
single coke-breeze side wall. The cupboard framing consists of 3 studs
of 4x1, left-rear, left-front & right-front which travel from floor to
ceiling.

The Zinc CW tank sits on 4x1 noggins run left-front to left-rear
studs,
and right-front-stud into rear-wall (no 4th vertical stud). CW Tank
weight
is somewhere south of 200kg by cupboard size (55W 60D 60H cm).


A plumber drilled an 18mm hole, 6cm up from the floor, centrally
through
the face of the 4x1 right-front stud for a 15mm pipe to a toilet micro-
basin.
In so doing he found the wood a bit powdery - an inch above it is very
hard.
The powdery wood extends around one of the 0.5"-wide nails.

This right-front stud appears to function as a vertical 4x1 wall plate
in that
it is 0.5"-wide nailed into coke-breeze & sits a fraction off the
floor. Other
studs go down into double-joists under the floor, rear has UB.

Slight water stain suggests a past cylinder seam leak just inches
away,
with the HW tank sitting on linoleum directing the leak accordingly.
All other wood, joists, check out as sound.


Q - Is it worth adding some extra fixings thro the 4x1 into the coke
breeze?
Q - Do coke-breeze voids, brittle nature, require a screw with epoxy
injected?

Crude structural engineering indicates 5:1 safety factor and the stud
does
seem to act as a wall plate and probably has more 0.5"-wide nails
further up.

Ta.