Introduction
Ripping out a bathroom or moving a kitchen for a few days? The work is fine—the problem is when the family can’t wash hands, make tea or flush safely. This guide shows you how to plan and install a safe, hygienic temporary water supply that keeps the household running and your schedule on track. We’ll cover the setup, backflow protection, hygiene, temperature control, and a clean handover. You’ll leave with a step-by-step you can reuse on every small job.
Table of Contents
Key Takeaways
- Temporary water done right keeps works moving and reduces client stress; many contractors find it prevents mid-job change requests and unplanned visits.
- A quick plan—valves, backflow, hygiene, drainage—can be captured in under 10 minutes and typically saves 2–3 hours of back-and-forth during the job.
- In general, aim for 4–6 L/min temporary flow for handwashing and food prep; more is overkill and increases splash/leak risk on makeshift setups.
- UK practice commonly requires backflow protection (for example, a double check valve) on hose-fed temporary connections to protect potable water.
- Hot outlets used by occupants should be limited by a mixing device; UK guidance commonly caps bath hot water to around 48 °C to reduce scald risk.
Why Temporary Water Matters
Many contractors learn the hard way: no water equals unhappy clients and rushed fixes. In occupied homes, even a day without a tap can trigger complaints and rescheduling. It’s common for teams to lose half a day to emergency workaround plumbing when a simple plan would have avoided it.
Problem
- Occupied homes need handwashing, kettle fill, light washing up, and WC use during works.
- Unplanned cut-offs lead to client pressure, site delays and sometimes non-compliant quick fixes.
- Hygiene risks (stagnation, cross-connection) and scald risks rise with makeshift setups.
Solution
- Decide the minimum service level (cold water for handwashing and kettle, or hot and cold?).
- Identify safe isolation points and a clean temporary connection with backflow protection.
- Keep it simple: short hose runs, WRAS-approved components, safe drainage.
Example
On a two-day bathroom rip-out in a one-bath flat, keep the kitchen tap live and provide a temporary cold supply to a small portable basin near the WC. Flow limited to roughly 5 L/min is enough. This setup typically takes 45–90 minutes, then you’re into demolition without client interruptions.
Plan the Setup
1. Map Isolation And Priorities
- Locate the internal stop tap, local isolation valves, and any branch valves feeding the work zone.
- Ask the client what they truly need for 48 hours: kettle, handwashing, light washing up, WC flush support.
- Note any vulnerable users (kids, elderly) for temperature limits.
- WRAS-approved hoses (food-grade for any drinking water use)
- Double check valve (or integrated hose union tap with check valves)
- 15 mm isolation valves and tee pieces
- Tap tails/adaptors, pressure gauge, hygiene wipes, bucket, PTFE, washers
2. Verify Pressure And Flow
- Cold static pressure: a quick gauge test at a hose bib is fine.
- Dynamic flow: open a quarter-turn at the kitchen tap and time a 1 L jug; aim for about 4–6 L/min on the temporary leg.
- In general, throttling to moderate flow reduces splash and leak risk on temporary fixtures.
3. Risk And Compliance Check
- Water Supply (Water Fittings) Regulations in the UK require backflow protection; temporary hoses feeding fixtures should include a double check valve as a baseline.
- Keep potable and non-potable hoses separate; clearly label.
- Avoid crossing hot and cold lines without an appropriate mixing device.
Safe Connection Methods
Options Compared
| Option | Use Case | Pros | Cons | Typical Time |
|---|
| Tee + Isolation Valve to Temporary Tap | Handwashing near WC | Clean, controllable flow, easy to flush | Needs a short copper/PEX run | 45–75 min |
| Hose Union Bib Tap From Cold Riser (with double check valve) | Quick cold supply for kitchen/utility | Fast, compact | Not for drinking without food-grade hose | 30–60 min |
| Temporary Mixer (TMV) on Hot/Cold Feeds | Families needing safe warm water | Scald protection, adjustable | More parts, needs balancing |
Connection Detail
- Use a 15 mm tee before the zone isolation for the work area and add an isolation valve to your temporary branch.
- Fit a double check valve on any hose-fed outlet to protect against back-siphonage.
- For drinking or food prep, use WRAS-approved, food-grade hose and keep runs as short as practical.
- Pressure-test the temporary branch to working pressure before handing it over.
Drainage For Temporary Basins
- Best: connect to an existing trap stub (for example, old basin waste) with a sealed adaptor.
- Acceptable: route via a trap into a nearby gully; ensure the hose drops continuously to avoid standing water.
- Avoid: open buckets or containers for grey water in occupied homes; spill and hygiene risks are high.
Hygiene And Temperature Control
Hygiene Basics
- Flush new temporary pipework until water runs clear and cool from the main, then disinfect contact surfaces (taps/hoses) with food-safe wipes.
- In general, avoid leaving hoses charged and stagnant overnight; isolate and drain where possible.
- Keep end caps on hoses when disconnected to prevent contamination.
Temperature And Scald Protection
- If you’re providing warm water, fit a thermostatic mixing valve (TMV) and set outlets sensibly. UK guidance commonly targets around 48 °C maximum at bath fillers to reduce scald risk.
- For handwashing, many contractors set mixed water around 38–41 °C for comfort and safety.
Occupant Briefing
- Show the client the isolation valve and agree a simple rule: “Open for use, shut when not needed.”
- Place a note near the temporary tap with “Do not drink” if it’s not a food-grade connection.
Recommissioning Without Callbacks
Step-By-Step
- Isolate and drain the temporary branch.
- Remove tees/valves not planned as permanent; cap and pressure-test the restored lines.
- Flush hot and cold until temperatures stabilise at normal service levels; purge air and check for discoloured water.
- Check all permanent fixtures for normal flow: many contractors aim for around 6–8 L/min at basins and 9–12 L/min at kitchen taps post-works (site-dependent).
- Inspect for weeps at all disturbed joints 15–20 minutes after pressurising, then again before you leave.
- Document what you changed and where the main isolation remains.
Real-World Example
Bathroom refit, two days, family of four:
- Temporary cold feed with double check valve to a compact basin near WC; drainage via sealed adaptor to old basin waste.
- Kitchen left live for tea and washing up; flow limited at temporary tap to roughly 5 L/min.
- Result: zero unplanned visits. Client had water when needed, and the crew saved an estimated 2–3 hours by avoiding mid-day workaround plumbing.
Frequently Asked Questions
Do I Need Backflow Protection On A Temporary Hose?
Yes. In the UK it’s common practice under the Water Supply (Water Fittings) Regulations to fit at least a double check valve on hose-fed temporary connections to protect potable water from back-siphonage.
Can Clients Drink From A Temporary Hose Connection?
Only if the full temporary path is suitable for potable water: WRAS-approved, food-grade hose, hygienic fittings, and a clean connection. If in doubt, label it “Do not drink” and direct clients to a standard kitchen tap.
How Long Can A Temporary Setup Stay In Place?
Keep it as short as practical—typically 1–3 days for small jobs. In general, the longer hoses sit charged and unused, the higher the hygiene risk. If it must stay longer, plan daily flushing and clear labelling.
What Flow Should I Target?
For handwashing and kettle fill, around 4–6 L/min is usually sufficient. Higher flows add splash and leak risk on makeshift fixtures without adding real benefit.
How Do I Prevent Scalds?
Use a TMV on any temporary mixed outlet and set sensible temperatures. UK guidance commonly caps bath hot water around 48 °C; for handwashing, many contractors aim for 38–41 °C.
Conclusion
Temporary water is one of those details that makes or breaks an occupied-home job. Plan the isolation and backflow, keep flows modest, protect hygiene, and brief the client. Capture your setup plan with photos and a quick voice note so everyone’s aligned. If you want less admin, use Donizo: dictate your site notes into a clear scope with voice-to-proposal, send a branded PDF for acceptance with e-signature, and convert accepted proposals to invoices in one click. That’s more time on the tools—and happier clients.