Plumbing Work
Plumbing in a new shop covers all water supply, drainage, and waste systems. It ensures safe delivery of clean water, efficient waste removal, and compliance with UK building regulations. Below is a full breakdown.
Pipework & Water Supply
• Incoming Supply
- o Water enters from the main supply (usually under the pavement) through an approved stop tap.
- o In retail shops, supply pipes are typically copper or multi-layer plastic (PEX or PB) with WRAS-approved fittings.
- o Pipes are sized based on expected demand e.g., a small retail unit with one WC and one sink may only need 15 mm pipes, while larger units may require 22 mm mains feeds.
- o From the stopcock, water lines run to toilets, hand basins, kitchenettes, and any display/demo areas needing water.
- o Pipe runs are kept as short and direct as possible to reduce heat loss and pressure drops.
- o All pipework must be properly clipped, insulated (especially in unheated voids), and pressure tested before finishing.
Toilet Preparation & Installation
• Drainage First
- o Soil pipes (for toilets) and waste pipes (for sinks) are installed early in construction, before floors are finished.
- o Soil stacks (vertical pipes) are typically 110 mm uPVC; waste pipes for basins 32–40 mm.
- o All pipes slope towards the main drain at recommended gradients (1:40 for wastes) to prevent blockages.
- o After tiling and the walls are finished, toilets, basins, and taps are installed.
- o Toilets are usually close-coupled or back-to-wall, with concealed cisterns to save space.
- o Basins include mixers or sensor taps (if high footfall is expected).
- o All connections sealed with WRAS-approved sealants and fitted with isolation valves for maintenance.
- o Each waste outlet fitted with a water trap (U-bend) to stop smells.
- o Adequate ventilation (mechanical extract) is required to comply with Part F of UK Building Regs.
Drainage Systems
• Internal Drainage
- o All waste and soil pipes connected to the main sewer line or a private drainage system.
- o Inspection chambers may be required for maintenance access.
- o External connections sealed and protected from frost.
- o Rainwater drainage (if applicable) connected separately to soakaways or storm drains.
Hot Water & Heating (If needed)
• Water Heaters
- o Small electric point-of-use heaters for basins are common in retail shops.
- o Larger units may need a small hot water cylinder or a combi boiler if heating is also required.
- o If radiators or underfloor heating are used, these require separate pipe loops connected to a boiler or heat pump system.
- o Pipes should be insulated to reduce heat loss.
Fixtures & Fittings
- • Sinks/Kitchenettes: Stainless steel or composite sinks with integrated taps and drains.
- • Drinking Water Points: Filtered cold water taps or fountains may be added for staff or customers.
- • Backflow Prevention: Double-check valves on supply lines feeding appliances to prevent contamination.
Accessibility & Maintenance
- • Accessible Toilets: Where required by law, at least one accessible WC with enough maneuvering space and grab rails.
- • Shut-Off Valves: Easily reachable isolation valves for all major feeds.
- • Access Panels: Panels in walls/ceilings for inspecting hidden pipe runs.