Making a floor access panel

[endecotp]

Dear Experts,

What’s the best way to make an access panel in a chipboard floor?
It’s in the floor of a cupboard, to access pipes and cables.
I’ve considered panels like these:
https://www.screwfix.com/p/manthorpe-access-panel-white-243-x-193-x-16mm/20924
but I don’t think they’re strong enough.
I can cut a square out of the existing flooring and re-fit it, but how exactly? I was looking for a metal profile that I could use and found “Z profile” like this:
https://www.ebay.co.uk/itm/ALUMINIU...074752?hash=item2cd53c8700:g:vdUAAOSw1nRbETfa
but its dimensions need to match the flooring, and it will protrude above the rest of the floor (unless the floor were routed).

Any advice?

 

[JohnD]

you can cut a rectangle out of the floor, and use it as the hatch. Make it a generous size.

You will want it to rest on the joists, so identify, from the lines of nails, where the joists run, and saw down their midpoint for each side of the hatch. They might be around 400mm apart. A circular saw with TCT blade is best for this. There will be dust. Adjust the depth of cut to match the thickness of the board so it hardly scratches the joists.

Then, cut across between the joists to finish your rectangle. Cut it a bit bigger than you want the access hole to be. if you have a multicutter you can use it to cut the corners trim.

Cut and fit struts (noggins) to fit tightly between the joists so that your hatch, and the cut ends of your old floor, can rest on them. You can skew-nail them, but it may be easier to drill one or two diagonal pilot holes through the struts and use long screws, because the strut may move out of place when you hammer. The strut is positioned so that half of it supports your panel, and half the old floor.

Fit it down with screws having large countersunk heads so they will be easy to take out when you need access. Drill and countersink first.

You can fit a floorsafe in much the same way.

Put traps away from the door and traffic areas, preferably in a corner where they will not be walked on, as they might squeak.

 

[Tigercubrider]

Is it a walk in cupboard? If it's a standard size, nobody will walk on it.
So long as you're sure there are no pipes of cables under the area, you can cut the hole by drilling, then using a jig saw. The hole for the saw could be made bigger to allow a finger to lift it out.

If minimal weight is going on it, a small scrap of timber can be shoved under the floor and screwed through to create a rebate- it may not need need something on all four edges. Even a diagonal on each corner is fine. The trap could be screwed (or not)

 

[endecotp]

An issue with using timber is that there isn’t much or any clearance between the bottom of the floor and the top of some of the pipes. I could support it just at the corners but I’d prefer something a bit more solid / sealed.

I quite like the idea of the Z-section aluminium profile, but it’s not quite the perfect shape; I was hoping someone would know what I have to search for to find something better.

 

[Tigercubrider]

If you could accurately cut the door at 45° it would more or less self support.
But by the sounds of it the pipes are close.
Without an image it's hard to say- you could fit metal strapping as supports

 

[endecotp]

If you could accurately cut the door at 45° it would more or less self support.

That’s a thought! Though of course it would drop down by the thickness of the cut.