Expenses - claim from work or in tax returns?

I'm about to reveal my complete taxation ignorance here, so be gentle with me.

I started a new job in the last year (PAYE) and put in each month for fairly standard expenses, taxi fares, hotel bills, air fares, etc.

But I mainly work from home and have bought a lot of equipment since I started the job, including a new desktop and laptop computer, printer, general office furniture and stationary, etc.

I could opt to work from my company's office - where all this equipment would be provided - but it's just much easier to work from home.

Because of this I haven't been claiming expenses on the stuff I've bought - I checked with a colleague and he hasn't claimed for similar purchases either.

So how does this work? Am I allowed claim expenses on such work-related purchases? If yes, should I be claiming them from my employers, or is there some way (even when I'm PAYE, not self-employed) of using them to reduce my tax bill?

Any advice would be appreciated, thanks.

The scenario you describe, working from home, while familiar to me seems a little bit odd.

If the employer wants an employee you to work from home, the "normal" set-up is that they provide the tools and equipment to do so, whether this be phones, computers , office equipment, stationery, etc on thge understanding that this equipment is, and remains at all times, the property of the employer.

Did you have any discussions with your employers about purchasing all this stuff before you went ahead and incurred the expenditure?

Did the purchasing / IT department have any input to minimum specifications, leases, security requirements, maintenance contracts, etc?

The Revenue allow standard annual expenses to each PAYE worker based on his / her profession, but I can't envisage a them allowing you to write off what is essentially capital equipment against your taxes. This would be the norm for self-employed sole-trader or a limited company.

I don't see the tax write-off being applicable here so IMO you need to talk to your employers about re-couping your costs.

I would claim them all from work if they agreed it in the first place

As your employer is supplying all the office gear at place of work and it is your choice to work from home I can't see that revenue would allow a claim for your home office. So many homes have computers, laptops, printers housed in the spare room/office as part of standard home furnishings.
I think the question is would you have most of this equipment anyhow for own use.