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Comment by ErroneousBosh | Hacker News Reader

> Stainless steel costs much more, but total project cost goes up less than 10%.

I think people are often surprised how little materials cost affects the total cost of a job.

I'm having this argument at work, where I want some more expensive cabling installed in a bunch of offices across Scotland so it doesn't need to be done again in another ten year's time, but "that stuff is so expensive, do we really need it?" is what I'm running up against.

So as it turns out today I'm giving them a breakdown of the cost of the job. Guess what the expensive bits are?

Did you guess "wages for two guys, hotel rooms for two guys, 800 miles of diesel, and a couple of ferry tickets?"

Well, you're way ahead of today's crowd then.

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I've worked on a few big EPC projects in a specialised industrial sector, including some in the UK. Three things drive the first digit of cost, assuming you've hired relatively competent engineers and constructors:

1. (Design) Building floorplate and architectural complexity (i.e., divergence from 'big box')

2. (Construction) Schedule adherence. Almost any one-off expense to stick to the schedule is worth it, but to your point, these are often challenged or delayed. Building and testing equipment on skids off-site is almost always worth it.

3. (Design/Commissioning) Schedule adherence. For commissioning this is typically driven by design choices (did you pick a high-TRL process, or if not, do all the work required to mature it in parallel to construction?) and by building the right commissioning team (knows their job, knows the plant).

If more expensive plant & equipment gets you ahead on any of these 3, 99% of the time that is an overall optimisation.

Not permitting and regulation? We're told that is the biggest impediment to development.

Permitting and regulation is generally a sub-component to each of the three things mentioned, and can be a major factor in schedule adherence for large scale construction projects. Whether that is the primary impediment or not is often a factor of the specifics of the project (and its design) and the overall environment. During major events (e.g. COVID), materials access and availability was a far more challenging aspect of schedule adherence for most large projects than any other factor.

I've never worked in this field as the GP, but I have family that do and I've heard plenty of stories and made my own observations, but definitely take my two cents with plenty of salt. Maybe GP will reply also.

A week late but... in my experience (potentially sector/location specific but I don't think so), most high-risk licensing and permitting activities come before construction starts, and certainly almost always before above-ground construction starts. So regulatory issues may challenge overall project viability, but you tend to know before cash is sunk if you're going to be, for instance, refused planning permission.

I was once working on a one off build and also on a smaller build at the same time. The smaller build was built start to finish as per the plans, the larger one was choices all the way.

The net result, we topped out and roofed the big house, then built the small house in its entirety while the owners of the big house chose their windows. Add that in favour of waterfall design...

In general, in the UK, labour costs dominate. How do people not understand that?!

This is what's interesting with AI pricing at the moment - it has gone from "a fraction of the equivalent labour cost" and so people have tried to cut staff, and is moving to "on par with labour cost" and all the calculations change.

Not just the UK, labor is usually the dominant cost of anything.

Our house flooded about half a foot a year or two ago. I had to replace all the baseboards. The damage was assessed at $40k. I tried to contact contractors to do the work, but the job was so insignificant compared to other jobs in the area, and we were in the middle of getting our house raised, that it was taking forever.

Including tools I did not have prior, material costs ran about $5k - $7k. I did the work around my job and other obligations, so about one day a week for a couple of months. If I were to honestly guess, it probably took me about two weeks. And that's measuring, cutting, installing, caulking, and painting. And there were some inefficiencies in my process.

> I think people are often surprised how little materials cost affects the total cost of a job.

It's because they frankly never did it. Nobody that had to contract something around the house is surprised by cost like that, it often costs more than price of renting equipment + you doing it yourself 3 times slower than an expert would did it, even if you're paid well.

There is reason there is so many DIY channels, labour costs are high and install costs of some stuff can be ridiculous (like 2 hour job to install AC costing more than cheap AC unit).

That's also partly the reason the more expensive materials are used - if they offer savings in labour (say way faster to put in), they might be worth it vs paying someone for more hours

Yeah. I mean I just had some concrete slabs laid to put a bike shed on (literally bikeshedding, the colour is green, that's what it comes powdercoated in from the supplier, take it or leave it).

It was 300 quid.

I could not buy the materials for 300 quid.

Two guys showed up with eight slabs, half a tonne of Type 2 and half a tonne of sand, and then the next day the landscaper showed up and did about six hours of work to dig it all out, fill it all in, and put the slabs down.

It's absolutely perfect, exactly how I wanted it, and it would have taken me a couple of days and cost far more - and I'm quite good at that kind of stuff, it's just not what I do all day every day so the landscaper will be far better at it.

My experience when i was in the trade is very few people know what perfect looks like, and so are perfectly willing to forego decent workmanship in favour of cheap. One of the reasons I left the trade, you could make more money doing a bad job, and I had no desire to do that.

It's why plumbers use $25 sharkbite fittings now instead of soldering in a $2 copper fitting. But of course the sharkbite relies on a rubber O-ring and will probably leak in 10 years, the plumber will be long gone or the property probably under new ownership who don't remember.

Softalker is right-on in his warning:

We usually have a few freezes in the winter and some homes' pipes freeze. I was surprised, in speaking to a plumber, to find that pipe clamp installation had come to dominate the repair market (as opposed to repairing/replacing the leaky pipe).

In his first year this plumber had arrived at the plumbing supply house to find all pipe clamp orders backlogged two weeks! He thus determined to, during the warmer months, stockpile a cache of pipe clamps for the coming winter.

Furthermore, as SofTalker states, the fitting is usually left in-place instead of being replaced! Yet one more reason to have a prospective home inspected by someone who is very knowledgeable.

Automated radial welding for pipes seems to be slowly reaching small, plumbing-sized pipes.[1] This has been around for years for larger pipes, but the equipment is now down to home plumbing diameters. Still too expensive, though, at around US$10,000.

[1] https://www.youtube.com/shorts/Jr1TZW8dKCw

That's very nice but I doubt it will replace pipe clamps in ease of installation and cost in a real-world repair environment. Many leaks in say steel galvanized water pipes are the result of corrosion. Pinhole leaks form, then more and then enough water leaks to be noticed on either exterior or interior wall. Jose the Plumber will leave his radial welder in the shop (b/c power is out anyway in the affected area and he doesn't carry a generator on his truck) and reach for his box of pipe clamps. Problem solved and on to the next job.

Propress compression fittings which use a hydraulic press are effective enough for domestic water pipes, along with traditional solder joints.

Electrical compression fittings are excellent too, but some engineers still specify exothermic welds (cadwelding) for grounding conductors in particular.

I did a project a couple years back with a mechanical contractor that used a similar machine to the one in the video you shared, except theirs was a bit larger ;) They were welding 18” HPDE pipes together for a geothermal district energy project, we were laying some puny 2” schedule 80 conduit that was glued together with primer and cement for future fiber cables that will connect to the meters of the customers of the district energy system.

ProPress are a (high-quality) solution but IIRC for copper piping.

PEX water piping expands and fails less(than galvanized) in freezing temperatures. This is the current accepted replacement for galvanized water piping.

PVC piping is also used but doesn't develop the pinhole leaks that galvanized steel pipe does. However it can fatigue and develop leaks.

AFAIK all can be patched with, ta-da, pipe clamps!

But most water leaks, especially in winter freezing, arise in old rusting galvanized steel piping. I'm not a plumber but I was a condominium association officer and president and so got to choose, watch and pay for repairs.

We had only copper, PVC and galvanized water lines. The copper was well underground and so failed only once in 20 years due to age and a nearby tree shifting the pipes. The PVC never failed but we had almost none. The galvanized pipe was a guaranteed failure every winter unless we took serious precautions when temperatures dropped.

>I think people are often surprised how little materials cost affects the total cost of a job.

Because people don't understand how much compliance and box checking and check the guy who checked the last guy's work there is in a "you need government permission for this and not the easy permission they give a homeowner deck project" sized construction project.

> Did you guess "wages for two guys, hotel rooms for two guys, 800 miles of diesel, and a couple of ferry tickets?"

Yes, but I happen to sell and run electrical work so it’s an easy question ;)

I hope you’re prepared for a huge amount of bike shedding… but if we pick this color, we can save a couple of dollars…

It's going in a suspended ceiling so it has to be purple.

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