Having worked in the building trade and an office environment i always argue that working in an office is far harder than physical labour. I think it used to be the other way round where builders worked their nuts off and office workers sloped off early. Nearly all the builders i know slope off at 2.30-3pm each day, only work Monday to Friday and are quite lazy and slow.
I work in an office and start at 8.30 and finish at 6.15 often staying later. I also log in in the evening and weekends.

With NPN, I would say that I prefer not going home physically f**ked after a days work, but I've reviewed my previous position, and will accept that office work can be taxing, and is more stressful, its really depends on which you prefer.

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Office work better in the cold and wet months

Building/outside work better in spring and summer.

Both can be stressful when things don't go to plan.

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while I was still trying to get started in my chosen career, I worked for my uncle and his building company, mainly fitting kitchens and block paving drives. Loved it but it wasn't what I wanted to do longterm. I also remember having to spread three tonnes of sand one scorching summer's day and was absolutely knackered.

I was only an extra pair of hands then and am much more senior in an office job now which has high levels of stress and pressure, which sometimes I wonder if it's worth it but I like what I do and as long as I can see an end or reward to the extremely stressful times then I can justify it. That said the mental tiredness eventually translates to physical tiredness due to sleeping less, not eating properly etc.

But I'd guess if you own you own building company then you also put yourself through the mental stress of running a company.

I know many of them too that's why neither i, or my colleagues, ever employ them.
As for office work being more tiring. Anything's tiring when you're not in control. If you were then it wouldn't be but physical work is always tiring, regardless.
I do a fair amount of physical labour and equally a good amount of 'office work' and the physical is obviously harder. Rarely do i ache after being on the phone or typing quotations/invoices.

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This is something I think about a lot.
I have worked inside in retail and went home feeling mentally drained, but now I work outside as a Landscape Gardener and go home feeling physically f*×#ed. Sometimes a little mentally drained from working with some proper idiots.
Now I couldn't ever imagine being a job which involved working inside and being in the same place everyday.
But like someone said earlier its all dependent on the weather. When it's sunny it's the best job ever, but when it's pi$$ing it down and you see people sat there at there desk in a nice dry, warm office you slightly envy them.

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