| Two
models Available:
ECON
push-up trap. Anti-wind uplift mechanism to
prevent the trap from falling if there is a severe
wind gusting.
ECON
hinge-down trap operated by a twin fingertip-activated
release. The trap is fixed to the frame by two factory-fitted
heavy duty hinges.
Composition:
ECON
PU & HD injection-moulded polypropylene door and
frame. All models have integral closed-cell vapour
seals between frame and ceiling, and between the trap
and frame.
Sizes
See
table. All model suit 600mm joist centres. They can
also be used with other joist centres by cutting a
joist and trimming the opening (subject to structural
considerations).
Appearance
ECON
PU & HD: trap and frame have a lightly textured
scuff-resistant white finish which blends unobtrusively
with a classic brilliant white ceiling.
Optional
extras
ECON
Loft Ladder twin section telescopic loft ladder,
suitable for floor to floor heights of 2210 to 2670mm.
ECON
Hinge Down door release pole (450mm). Also available:
ECON 30FR model with 30 minutes fire resistance and
Class 0 flame spread and ECON1FR with 1 hour fire
resistance
Condensation
control
Thermal
insulation at ceiling level produces a cold roof with
an increased condensation risk due to moisture vapour
migrating into the loft space from the dwelling below
. Most of the water vapour in the roof void comes
from washing, drying and cooking within the house.
It enters the void by diffusion through the ceiling,
and by air movement through gaps around a traditional
loft trap, pipes, ceiling roses and cracks. With a
conventional unsealed loft hatch, approximately 50%
of vapour transfer by air movement occurs around the
hatch cover (BRE Digest 270). With an econstruction
products sealed Loft Trap this can be
cut to almost zero. BS 5250 incorporating Amendment
1 is now the main means of compliance with these requirements.
BS 5250 Amendment 1 Clause 8.4.1.2 recognises that
a totally airtight (convection tight) ceiling is extremely
difficult to achieve in practice, but provides advice
on how to construct what has been termed a well-sealed
ceiling. It includes the following specific requirements
for access hatches:
b)
No access door or hatch should be located in rooms
where large amounts of moisture are produced, including
kitchens or bathrooms.
c) The air leakage rate through an access
hatch, including its frame, when tested to BS EN 13141-1:
2004 4.3 is less than 1m3/h at a pressure difference
of 2Pa. This is the first time that loft access hatches
have had to achieve an air leakage performance in addition
to the minimum thermal performance of Part L.
Thermal insulation
Thermal insulation laid on the ceiling is a simple
and cost-effective method of conserving heat and meeting
building regulations. However, the loft trap should
also be insulated to avoid heat loss. Insulating a
conventional trap by laying insulation on it is awkward
and not reliable. Heat loss can also occur when the
trap is inadequately sealed against draughts, allowing
warm air to escape around the edges and increasing
moisture transfer. |
