DMG 04. Junior Ranks' Single Living Accommodation JRSLA

DEO(W) Design Guide JRSLA 2 General Functional & Design Requirements
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staggered so that the opening of one bedroom door will not disturb the occupant
opposite. Floor and wall finishes along busy circulation routes should be chosen to
minimise noise.
Control of external noise can be achieved through the sound insulation of the
building envelope. The density / mass of the construction will determine its sound
insulating properties, with components, such as doors and windows, creating local
penetrations in the building envelope. For the sound attenuating qualities of the
building envelope to be maintained, the penetrations within it should be kept to a
minimum, particularly on the elevation exposed to most noise.
Windows should be double glazed to provide both thermal and sound insulation.
The use of secondary glazing can provide additional sound insulation by creating a
larger air gap than can be achieved with a double glazed unit alone. To be
effective, the secondary pane must be securely closed.
The design of the building fabric for sound insulation, must include protection of
the top storey, possibly with a concrete over-slab, where noise levels on the site
dictate. The sound insulating properties of a traditional timber and tiled pitched
roof will not be good enough to control noise levels from low flying aircraft, for
example. Buildings on air stations will generally be subject to greater levels of
external noise than on other sites, and the detailed design of the JRSLA should
take this into account.
The ventilation system within the JRSLA needs to be designed to ensure low noise
levels within the bedsitting rooms. This is particularly important with ensuite
WC/shower rooms, which rely exclusively on the mechanical extraction of air, and
which are sited so close to sleeping areas.
Acoustic / Sound insulation measures should not conflict with the ventilation, fire
and health and safety requirements of the design.
2.5.3 Visual Criteria /Colour
The materials, building massing and density of development should be appropriate
to the site and building use. The quality of building materials can vary the
appearance of the JRSLA project through the choice of scale, texture and colour.
Local variety of colour and form within repeated elements of construction can add
identity to individual accommodation blocks.
2.6 CONSTRUCTION/COMPONENTS
2.6.1 Building Structure
The small scale nature of JRSLA buildings suggests a load-bearing form of
construction for reasons of economy. The majority of JRSLA buildings will be
loadbearing brick / block, with pitched roofs with clay or concrete tiles. This is
supported within the MOD Manual of Reference Costs for JRSLA, and this form of
construction is assumed within the following notes.
The case for a framed structure may be supported where the risk to the building
from terrorist attack is considered to be high. In these cases the protection against
building collapse, following bomb blast, is best achieved through a structural
frame. Whatever structural solution is adopted, measures to combat building
collapse and injury from flying debris must be considered as part of the design.
Aircraft can create pressure vortexes which can cause uplift damage to roof
coverings. A risk assessment should be carried out on JRSLA projects, on sites
adjacent to aircraft runways, to determine whether this will be a factor in the
design of the roof.