Regs for a floor hatch, headers and trimmers.

4 Apr 2017
Reaction score
United Kingdom

I have cut a hatch in the timber floor in my hall and need to cut the middle joist and frame the hole.
There is a pipe which can't be moved and will restrict the size of usable space so
I want to fit a single header at each side.

The hole is under 4ft and the joists are less then 3ft from supported joist ends.
Can I use single headers to maximise the space?

Do I have to fit trimmers?

If I have to fit trimmers can someone recommend the best hardware to use to join them
to the existing joists?

Must the joist hangers be exactly the same height as the joists?

I used to make furniture so I know my way around tools and timber but I'm not familiar
with construction Regs. I have used google and have found a lot of information but
can't find the specific answers to my questions above.

Many thanks.


  • Angled view.jpg
    Angled view.jpg
    50.9 KB · Views: 93
  • Plan view.jpg
    Plan view.jpg
    36.7 KB · Views: 84
  • View from below.jpg
    View from below.jpg
    44 KB · Views: 84
Sponsored Links
I'm up at 5 so I'm going to my scratcher. If anyone replies I will get back to you tomorrow.

Thanks again.
For what purpose have you cut a hatch in your hall?
Is the hatch already opened up to the dimensions in the diagrams?
Why cant the pipe be moved - what pipe is it: gas, water etc?

Thanks for replying. It's actually my mates flat. It's a ground floor tenement flat and he wanted the hatch in the hall. He wants it to be a feature so it's brass door furniture and a nice finish all round. I told him to put it in his cupboard but he is a bit mad and insisted it went in the hall.

The hole is already there and the pipe is a water pipe but this is only access to a crawl space so the only thing going through this hole will be tradesmen and whatever equipment they use.

The hole is big enough for a small enough guy to get down but the joists are only 300mm apart and he wants the middle joist cut in case future tradesman need the extra space.

This was supposed to be fairly simple so I don't want to get involved in moving pipes around if it's not necessary.

I want to use whatever is absolutely the correct method. I'm not looking for shortcuts. But I obviously don't want to be doing work that isn't required.

Sponsored Links
Excellent news. No need to trim the joist then. Tory rule also means that soon we'll be able to use small children to do these tasks for a bowl of gruel and a corner of a kennel. We can just pour these boneless waifs down a hole the size of a coke can.

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local