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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. |