"Richard" wrote in message
...
Hi, I'm about to embark on boarding out my loft for light storage, and
felt that it would be a good time to also remedy the lack of fire
breaks in my mid terrace house.

Do you mean there is no wall in the loft between each terraced house?

First fill the gaps between the joists with insulation. On top of the joist
install slabs of thick ridgid foam. On top of that the boards. The secews
go through both and into the joists. This elimintes cold bridging through
the joists and increases the insulation thickness without using extra
joists.

It is best to lay a vapour barrier on the loft floor above the plasterboard.
This is poly sheet. This will prevent water vapour entering and condensing
in the loft. Also seal up any pipe and wire holes in the loft.

Two ways to do the walls:

1. Extending the wall up into the roof space is best using lightweight
blocks. On the top of the existing walls use a course of highly insulated
blocks to reduce heat loss through the wall into the cold roofspace.

2. Use wooden or metal studding and Fermacell boards. These boards only
need one layer and will conform to fire regulations.
http://www.fermacell.co.uk/

You may want to insulate the sloping roof having gone this far. Make sure
any air gaps are clear.

You mention soundproofing. Why? These walls are in the loft.
Soundproofing will be on the loft floor via the insulation and boarding.

Also fit a sealed and insulated loft hatch.