Replacing Subfloor

Jimmy54321

Hi all,

I'm about to install laminate flooring in my flat (1st Floor) and after having a joiner in to look at the place he recommended replacing the sub-floor in the lounge. Flats were built 1986 and as far as I'm aware the existing sub-floor is the original The Joiner has since gone Awol and due to time constraints I am likely just going to have to crack on and install the laminate myself and as such also the sub-floor. The other floors are all fine and produce no movement or noise so have decided to leave them be.

The current sub floor is sections of chipboard laid down over wooden joists however there appears to be some give in areas of the floor with quite noticeable creaking as a result which I would like to eliminate before putting laminate down. The Joiner who looked at it reckons that the boards are laid in a way that there is too much void between one joist and the next in certain portions of the floor which has lead over time to the give or dip in certain sections of the floor.

I am considering replacing this sub-floor myself to save some money as I am a first time buyer and cash/time is beginning to become a bit scarce. I was hoping if people could give me some advice on this type of job and whether or not I should even attempt it myself. To me it sounds fairly simple in theory as far as I can see the process would be to remove the existing boards, ensure a level sub surface, perhaps add some extra support in the areas that were giving before and then secure a new sub-surface over the joists allowing some gaps for expansion and not laying the boards directly in line with each other.

I'm worried that I'm massively over simplifying the job and am potentially opening a can of worms for myself. I appreciate its hard for people to say without actually seeing the sub-floor and whats under it but If I could get any kind of reassurance as to the process of doing this and whether or not its more work that I am making it out to be. Also if anyone could advise on what potential problems I may come across that would be good. I wouldn't be against paying a pro to do this its just they all seem to be so booked up in my area and I'm struggling to find tradesmen to do anything at less than a months notice as they all seem to be tied up with 'big jobs'.

P.S. Before anyone asks I have permission to lay the laminate from the management company, have purchased high quality acoustic underlay and have discussed it with my neighbors who have no issues and without wishing to offend them, are an older couple and are very hard of hearing anyway.

Thanks

troffasky

Have you had the subfloor up? If he's saying the subfloor isn't adequate then probably what he's getting at is that the thickness of chipboard isn't sufficient for the width of the joist spacings. You will need to think about how much height you've got to play with, once you've added the thicker subfloor, acoustic underlay and floor. Are you going to need to trim door frames, doors, adjust skirting boards? Ply's a longer lasting, stronger solution than chipboard but T&G ply is more expensive than chipboard.


I think flooring is within the realm of the enthusiastic amateur/DIYer [unlike, say, making changes to gas pipework]. There's plenty of resources out there on the internet to educate yourself with.


Just be prepared for:

• Spending a lot longer on the job than you'd originally envisioned
• Making expensive/time consuming mistakes
• Having to buy tools you're not sure you'll ever use again
• Not quite getting the same fit and finish as pro

Hayley20013

Sorry I can’t advise but I would be interested to see what you find when removing the subfloor. We have dips along some parts of our floor too and from what I can work out we have large panels (not sure what they are called) running in the same direction as the joists. Each piece is the same width as the room so quite large. I thought they had to be laid on the opposite direction for more support but I don’t really know what I’m talking about!