Replacing some floorboards

[stealthwolf]

Upstairs landing, outside the master bedroom and outside the toilet room and bathroom are very creaky. These are high traffic areas. I've also felt dips through the carpet. I had planned to lift the carpet up later this year to have a look but we had the alarm guy round and he wanted to route the wire underneath.

There are marks where it looks like where the previous owners had the floorboards cut and lifted. Where they've screwed it down, it's split either the edges or the tongues:

I was going to buy replacement T&G boards to fit but these are ~98mm wide which doesn't appear to be a standard size in any of the DIY sheds.

Am I okay going for standard 119mm wide boards and then trimming down? Or is there a better alternative?

 

[big-all]

the boards are ex inch size then the machining removes about 6mm then the coverage is about 8mm less as they will include the tounge in the width
so a board will start as 125mm reduced to 119mm so coverage minus tounge width so about 110-112 coverage
without support for both edges off the board you are likely to get creaking

 

[Tigercubrider]

is there anywhere in the house that you can steal boards from where it won't show?
my loft was full of boards that the sparks had left when building it 50 years ago.
ok not full but more than enough to do a small room.

Your damage doesn't"t look too bad. I'd glue together what you have, and try to add some wood to the boards that have missing parts.
Then carefully screw down replacements, with extra noggins to support

 

[stealthwolf]

the boards are ex inch size then the machining removes about 6mm then the coverage is about 8mm less as they will include the tounge in the width
so a board will start as 125mm reduced to 119mm so coverage minus tounge width so about 110-112 coverage
without support for both edges off the board you are likely to get creaking

This is what I was looking at buying:
https://www.wickes.co.uk/Wickes-PTG-Floorboards-18-x-119-x-2400mm-Single/p/120833
But creaking is one of the things I want to avoid

is there anywhere in the house that you can steal boards from where it won't show?
Your damage doesn't"t look too bad. I'd glue together what you have, and try to add some wood to the boards that have missing parts.
Then carefully screw down replacements, with extra noggins to support

No extra boards anywhere in the house sadly. The loft was full of insulation that had been chucked out. Actually there might have been old floorboards screwed down for flooring but I chucked them out when I replaced the loft insulation and added my own loft flooring.

Whoever lifted the floorboards previously had put the screws in at odd angles. I was going to add extra noggins anyway since some screws were on the edges of joists and about to rip out.

 

[big-all]

to be honest with 18mm if you cant connect solidly to tie the edges together your better to leave a 1mm gap if possible as its surface rubbing against each other that creates the noise not the actual movement

 

[CortinaV8]

My landing was similar, quite a big junction for pipework and the boards/joists has multiple cuts and notches.

I replaced it all with plywood in the same thickness as it was easier to bridge the pipework and get better fixings.

 

[oldbutnotdead]

If you've got a router then yes you can trim wider boards down and recreate the tongue but CortinaV8's suggestion (use a big bit of ply) removes the problems of the edges of the floorboards not being supported where the joists have been notched for the pipework. If you're cunning you could replace say 6' x 3'-worth of T & G with the ply and use the T & G you've salvaged to replace the other boards which have been damaged. The screws will be in at weird angles because that's where what was left of the joists was (I've had to do the same myself for that reason)