How to create a Modular Wiring Estimate for Healthcare

Why wait several days for a quote, when you can generate a bill of materials yourself, then issue it for simple comparative pricing?

By following these few simple steps you could save days, freeing-up time to concentrate on the rest of your tender package. We are going to show you how to take arguably the most challenging sector to engineer, healthcare, to produce a simple, yet accurate schedule of materials. Based on un-armoured secondary cabling, and a Dali Lighting system.

MDBs/MDUs (Master Distribution Box/Unit)

1. Break MDBs down into No. of Ports required. Keep it simple. Assume separate Lighting and Power, and assume 9 Ports to be used throughout. (A different configuration may be pre-designed - even easier).

2. By DB, the quantity of circuits used = the number of ports required. Divide by 9 = MDBs.

3. Lighting MDBs, if no circuits, assume 10 Luminaires per circuit. If you don't want to 'locate' your MDBs and scale-off the Home Runs, then simply assume an average length of around 25m.

4. Power MDBs, like the Lighting, circuits = ports, so divide the total by 9, (per DB). If the design is not circuited yet, allow 6No power outlets per circuit, and again allow an average Home Run length of around 25m.

5. The only other implications are whether you want a pluggable DB Header, and what cable sizes are to be specified in the Home Run.

Lighting Materials

• 5c 2.5mm² Extenders, Lighting Tees, 5c 1.5mm² Luminaire Leads, 2c Belden PIRs/Switches

1. Qty of Luminaires = Lighting Tee & *1m 5c 1.5mm² Male to Free-end drop

2. Qty of PIRs = Lighting Tee & *1m 2c Belden Male to Free-end drop

3. Qty of Switches = Lighting Tee & 3m 2c Belden Male to Free-end drop

4. Qty of Luminaires, PIRs & Switches = Qty of Extenders. For budget purposes, you could list these as 2 average lengths of 3m & *8m (8m would be the total number of lighting circuits, and 3m would be total number of luminaires, PIRs & Switches minus the number of lighting circuits). *The 8m length is to cover a longer average for the 1st leg from the MDB to the 1st point.* *Check dimension from containment to grid. Check if luminaire supplier has pre-agreed length eg 2.2m.*

Power Materials

• 3c 4mm² Extenders, Power Tees & Fused Spurs for high level spurs

1. High level spurs = Fused Spurs (You need to identify switched and un-switched separately)

2. Low level Power accessories = Power Tee & 3m 3c 4mm Male to free-end drop

3. High level spurs + Low Level Power Accessories = Power extenders

4. Again for budget purposes, allow one simple average length of 8m.

That's it! Issue your list to the modular wiring manufacturers and they will appreciate that it is simpler to quote a list of materials than it is to print everything, understand the project, make allowances and assumptions, and then schedule it into their workload.

It is this element of assumptions and allowances which generates variables in the modular wiring manufacturer's quotes, which results in not comparing apples-for-apples, and puts the client in a difficult and confused situation.

For further help, advice or assistance, please contact us, and keep in touch for further articles, free advice and downloadable tools. We will create further articles in this series, identifying how to apply take-offs across all the sectors. If you don't feel comfortable doing these processes, please engage with us and we'll create the materials list required for any project.