Trap
In its broadest sense, the word ‘trap’ refers to a something that catches and holds things.
The 2018 International Residential Code (IRC), published by the International Code Council (ICC) defines a trap as: ‘A fitting, either separate or built into a fixture, that provides a liquid seal to prevent the emission of sewer gases without materially affecting the flow of sewage or wastewater through it… The trap seal is the maximum vertical depth of liquid that a trap will retain, measured between the crown weir and the top of the dip of the trap.’
The Illustrated Guide to Hot and Cold Water Services (BG 33/2014), written by Reginald Brown and published by BSRIA in 2014, it states: ‘Traps containing a water seal are essential to prevent toxic gases from the sewer system entering the building through the appliance drain. The minimum trap size and seal depth is detailed in Table 1 of Section 1 of Approved Document H. Traps are fitted to baths, basins, sinks and shower trays as a version of the so-called “U-bend”. In most cases the trap will connect on to the waste fitting plughole with a standard thread (1¼ inch BSP for basins and 1½ inch BSP for baths and showers). Traps for WCs are incorporated in the design of the WC pan. The water seal is continuously maintained in use but can disappear through evaporation if the appliance is not used for several months, for example when a property is vacant.’
The word trap can also refer to a two-wheeled carriage pulled by a horse.
See also: Boulder trap.
[edit] Related articles on Designing Buildings
Featured articles and news
Roof terraces and higher-risk buildings
Context, review, interpretation, case and guidance..
Sustainable Futures. Redefining Retrofit for Net Zero Living
More speakers confirmed for BSRIA Briefing 2024.
Employment Rights Bill; making work pay
‘Biggest uplift in employment rights law since the 1970s’
Architecture in Britain and Ireland, 1530 - 1830
Steven Brindle’s book is required reading.
Battle for Mill Road Free Library
Years of failures by the county and city councils.
The accolades that demonstrate and recognise outstanding achievement.
What is the Conference of the Parties ?
The who, where, what and when before no 29.
CIOB signs up to Green Skills At COP campaign
In preparation for COP29 on 11 November in Azerbaijan.
2024 ECA Industry Awards evening
Full list of electrical contractors scooping top prizes.
Briefing on the implications of the final Grenfell inquiry report
What it means for Architectural Technology professionals.
CIOB Art of Building photo contest 2024
International showcase for the very best photography of the built environment.
Celebrating architecture's eloquent champions.
Unusual perspectives on 1960s’ thinking.
AI and the challenges to intellectual property
The legal landscape of adopting AI now and in the future.
Worrying landscape for Welsh construction SMEs revealed.
In recent risk factor analysis report completed by CIOB.
Construction Sport survey highlights risks of dehydration
Supporting construction workers to avoid dangers.
Construction awards provide relief in wake of ISG collapse
Spike in major infrastructure awards, housing up but short of targets, are ISG collapse impacts yet to come.